Academic Appointments


Administrative Appointments


  • Postdoctoral Fellow, Lawrence Berkeley Laboratory (1984 - 1985)
  • Assistant Professor of Geology, Stanford University (1985 - 1990)
  • Associate Professor of Geology, Stanford University (1990 - 1993)
  • Associate Professor Geological & Environmental Sciences, Stanford University (1993 - 1996)
  • Associate Dean for Academic Affairs, School of Earth Sciences (1996 - 1999)
  • Professor Geological & Environmental Sciences, Stanford University (1996 - Present)
  • Professor by Courtesy Materials Science and Engineering, Stanford University (1997 - Present)
  • Chariman, Dept. of Geological and Environmental Sciences (1999 - 2004)
  • Chairman, Dept. of Geological and Environmental Sciences (2009 - 2012)
  • member, University Committee on Postdoctoral Scholars (2009 - 2010)
  • member, School of Earth Sciences Council (2012 - 2015)
  • member, Faculty Senate Committee on Undergraduate Standard and Policies (C-USP) (2012 - 2014)

Honors & Awards


  • Graduate Fellow, National Science Foundation (1977 - 1980)
  • Member, National Science Foundation, Presidential Young Investigators (1986-1991)
  • Fellow, American Ceramic Society (19--)
  • Fellow, American Geophysical Union (19--)
  • Fellow, Mineralogical Society of America (1990)
  • Mineralogical Society of America Award, Mineralogical Society of America (1992)
  • G.W. Morey Award, Glass and Optical Materials Division of the American Ceramic Society (1995)
  • Fellow in Undergraduate Education, Bass University (2003-2008)
  • Geochemistry Fellow, Geochemical Society and European Association of Geochemistry (2009)
  • Bunsen Medal, European Geosciences Union (2009)

Boards, Advisory Committees, Professional Organizations


  • Member, School of Earth Sciences Computer Committee, Stanford University (1987 - 1999)
  • Associate Editor, American Mineralogist (1990 - 1999)
  • Freshman Advisor, Stanford University (1991 - 1999)
  • Member, Earth Systems Steering Committee, Stanford University (1991 - 2002)
  • Organizer (with D. Dingwell and P. McMillan), MSA Short Course "Structure, Dynamics and Properties of Silicate Melts" (1995 - 1995)
  • Councillor, Mineralogical Society of America (1995 - 1997)
  • University Undergraduate Advisory Council, Stanford University (1996 - 1999)
  • Associate Dean for Academic Affairs, School of Earth Sciences, Stanford University (1996 - 1999)
  • Member, Earth Sciences Council, Stanford University (1996 - 2007)
  • Faculty Senate, Stanford University (1997 - 1999)
  • Chairman, Dept. of Geological & Environmental Sciences, Stanford University (1999 - 2004)
  • Invited speaker, International Silicate Melts Workshop (1999 - 1999)
  • Invited speaker:, Conference on NMR in Earth Sciences, Cambridge University (2000 - 2000)
  • Invited Speaker, Corning Science Fellows Conference; Goldschmidt Conference in Geochemistry; ACS Rocky Mountain Conference on Analytical Chemistry; Varian NMR User's Conference; NSF Workshop on Solid-State Chemistry; Varian, Inc. NMR Group Seminar (2001 - 2001)
  • Marsh O'Neill Award Committee, Stanford Univesity (2001 - 2001)
  • Member, Materials Council, Stanford University (2002 - 2006)
  • Member, Judicial Affairs Board, Stanford University (2002 - 2003)
  • Invited Speaker, American Ceramic Society National Meeting; Goldschmidt Conference on Geochemistry; International Mineralogical Association; Virginia Polytechnic Institute (2002 - 2002)
  • Invited Speaker, Goldschmidt Conference on Geochemistry (2003 - 2003)
  • Invited speaker, American Ceramic Society, Glass and Optical Materials Mtg.; AGU session on melt structure and properties; Plenary lecture: European Conference on Mineralogy and Spectroscopy (2004 - 2004)
  • Chairman, School Undergraduate Program Committee, Stanford University (2004 - 2005)
  • Invited Speaker, COMPRES workshop on high pressure melts, Albuquerque NM;Saint-Gobaine Glass Research Center, Paris; Centre de Recherche sur les MatÈriaux a Haute Temperature, OrlÈans, France; Symposium on Structure and Properties of Silicate Glasses and Melts, Institut de Physique du Globe de Paris (2005 - 2005)
  • Member, NSF review panel (2005 - 2005)
  • Invited seminar, Centre de Recherche sur les Matriaux a Haute Temperature, Orleans, France (2005 - 2005)
  • Humgrove Lecturer, University of Utrecht (2005 - 2005)
  • Invited speaker, European Geophysical Union (2005 - 2005)
  • Committee of Visitors, NSF Division of Materials Research (2005 - 2005)
  • Plenary speaker, Silicate Melt Workshop, Ludwig-Maximilians-University, Munich (2005 - 2005)
  • Guest Editor (with Roberto Moretti and Pascal Richet), Silicate Melts volume of "Chemical Geology" (2005 - 2005)
  • Invited speaker, International Mineralogical Association conference; Materials Research Society national meeting (2006 - 2006)
  • Guest editor (with G. Henderson and G. Calas), "Glasses and Melts" issue of "Elements" magazine (2006 - 2006)
  • Allan Cox Medal committee, Stanford University (2007 - 2007)
  • Invited Speaker, Canadian Society of Chemistry annual mtg., 5th Alpine NMR conference, 8th Silicate Melt Workshop, DOE Geofluids Workshop (2007 - 2007)
  • Invited Speaker, Rocky Mountain Conference on Analytical Chemistry (2008 - 2008)
  • Member, Nanoscale Sciences and Engineering Shared Facilities Program Committee (2008 - Present)
  • Chairman, Dept. of Geological and Environmental Sciences, Stanford University (2009 - 2012)
  • Member, University Committee on Postdoctoral Scholars, Stanford University (2009 - 2010)
  • Invited speaker, European Geosciences Union (Bunsen Medal Lecture); U.C. Davis, Dept. of Geology; PacRim Conference on Ceramic and Glass Technology; Institut de Physique du Globe, Paris; IUPAC Int. Conf. on High Temperature Chemistry (2009 - 2009)
  • Invited speaker, Glass and Optical Materials Div., American Ceramic Society, annual mtg.; keynote speaker, Goldschmidt Conference on Geochemistry (2010 - 2010)
  • Invited speaker, Glass and Optical Materials Div., American Ceramic Society, annual mtg.; NSF Workshop on Emerging Research in Ceramics, Carbon, Glasses and Composites; Vaughan Symposium, Rocky Mt. Conference on Analytical Chemistry; AGU annual mtg (2012 - 2012)
  • keynote speaker, Goldschmidt Conference on Geochemistry; (2012 - 2012)
  • Member, School of Earth Sciences Council, Stanford University (2012 - Present)
  • Invited Speaker, Corning "Realizing the Vision" symposium (2015 - Present)
  • Member, Faculty Senate Committee on Undergraduate Standards and Policy (C-USP), Stanford University (2012 - Present)
  • Invited Speaker, Corning Glass Research Summit (2014 - 2014)

Professional Education


  • PhD, UC Berkeley, Geology (1983)
  • M.A., University of California, Berkeley, Geology (1980)
  • A.B., Harvard University, Geological Sciences (1977)

Current Research and Scholarly Interests


Research
My research is focused on the measurement of the structure and dynamics in (mostly) inorganic materials, with the goal of understanding and predicting their thermodynamic and transport properties. These in turn fundamentally control a wide range of geological and technological phenomena. My students, postdocs, and I work primarily on disordered materials, including minerals, glassy and molten silicates and oxides, and ceramics. Our primary research tool is nuclear magnetic resonance (NMR). The materials that we study come from the natural laboratory of the Earth or are synthesized in our own labs. The problems that we address are tied to large-scale processes in geology and geophysics, as well as to those in high-tech industries. Among the former are the mechanisms of viscous flow in magmas and of solid solution in minerals from the crust to the lower mantle; among the latter are the optimization of glasses for flat screen computer displays and optical data transmission and of oxide ceramics for fuel cells.

Teaching
I have long taught a course in introductory geochemistry for undergrads at the beginnings of their careers in Earth sciences. Topics range from the formation of the chemical elements in stellar interiors, to high pressure and temperature phase equilibria, to aqueous solution chemistry, formation of oil and coal, and even the origin of life. At the advanced level I give a course on thermodynamics and structure of minerals and melts aimed at all graduate students who work with these "geomaterials." Recently I have begun teaching a course for advanced undergrads and for grad students on igneous processes.

Professional Activities
Geochemical Society Fellow (2009); European Geosciences Union Bunsen Medal (2009); American Ceramic Society Morey Award (1995); Mineralogical Society of America Award (1992); NSF Presidential Young Investigator (1986-91); associate dean, School of Earth Sciences (1996-1999); chair, GES (1999-2004); participation in professional societies, scientific conferences, and proposal and journal reviews in geochemistry, geophysics, mineralogy, inorganic chemistry, glass science, ceramics, and solid-state NMR

2023-24 Courses


All Publications


  • Evidence for Mixed Mg Coordination Environments in Silicate Glasses: Results from 25Mg NMR Spectroscopy at 35.2 T. The journal of physical chemistry. B Sen, S., Stebbins, J. F., Kroeker, S., Hung, I., Gan, Z. 2023

    Abstract

    The Mg-O coordination environment of silicate glasses of composition CaMgSi2O6, Na2MgSi3O8, and K2MgSi5O12 is probed using ultrahigh-field (35.2 T) 25Mg magic angle spinning nuclear magnetic resonance (MAS NMR) and triple-quantum MAS NMR spectroscopy. These spectra clearly reveal the coexistence of 4-fold- (MgIV) and 6-fold- (MgVI) coordinated Mg in all glasses. The MgIV/MgVI ratio implies an average Mg-O coordination number of ∼5 for CaMgSi2O6 glass, bringing NMR results for the first time in good agreement with those reported in previous studies based on diffraction and X-ray absorption spectroscopy, thus resolving a decade-long controversy regarding Mg coordination in alkaline-earth silicate glasses. The Mg-O coordination number decreases to ∼4.5 in the alkali-Mg silicate glasses, indicating that Mg competes effectively with the low field strength alkali cations for the nonbridging oxygen in the structure to attain tetrahedral coordination. This work illustrates the promise of ultrahigh-field NMR spectroscopy in structural studies involving nuclides with low gyromagnetic ratio.

    View details for DOI 10.1021/acs.jpcb.3c06419

    View details for PubMedID 38032847

  • Templated encapsulation of platinum-based catalysts promotes high-temperature stability to 1,100°C. Nature materials Aitbekova, A., Zhou, C., Stone, M. L., Lezama-Pacheco, J. S., Yang, A., Hoffman, A. S., Goodman, E. D., Huber, P., Stebbins, J. F., Bustillo, K. C., Ercius, P., Ciston, J., Bare, S. R., Plessow, P. N., Cargnello, M. 2022

    Abstract

    Stable catalysts are essential to address energy and environmental challenges, especially for applications in harsh environments (for example, high temperature, oxidizing atmosphere and steam). In such conditions, supported metal catalysts deactivate due to sintering-a process where initially small nanoparticles grow into larger ones with reduced active surface area-but strategies to stabilize them can lead to decreased performance. Here we report stable catalysts prepared through the encapsulation of platinum nanoparticles inside an alumina framework, which was formed by depositing an alumina precursor within a separately prepared porous organic framework impregnated with platinum nanoparticles. These catalysts do not sinter at 800°C in the presence of oxygen and steam, conditions in which conventional catalysts sinter to a large extent, while showing similar reaction rates. Extending this approach to Pd-Pt bimetallic catalysts led to the small particle size being maintained at temperatures as high as 1,100°C in air and 10% steam. This strategy can be broadly applied to other metal and metal oxides for applications where sintering is a major cause of material deactivation.

    View details for DOI 10.1038/s41563-022-01376-1

    View details for PubMedID 36280703

  • Monolayer Support Control and Precise Colloidal Nanocrystals Demonstrate Metal-Support Interactions in Heterogeneous Catalysts. Advanced materials (Deerfield Beach, Fla.) Goodman, E. D., Asundi, A. S., Hoffman, A. S., Bustillo, K. C., Stebbins, J. F., Bare, S. R., Bent, S. F., Cargnello, M. 2021: e2104533

    Abstract

    Electronic and geometric interactions between active and support phases are critical in determining the activity of heterogeneous catalysts, but metal-support interactions are challenging to study. Here, it is demonstrated how the combination of the monolayer-controlled formation using atomic layer deposition (ALD) and colloidal nanocrystal synthesis methods leads to catalysts with sub-nanometer precision of active and support phases, thus allowing for the study of the metal-support interactions in detail. The use of this approach in developing a fundamental understanding of support effects in Pd-catalyzed methane combustion is demonstrated. Uniform Pd nanocrystals are deposited onto Al2 O3 /SiO2 spherical supports prepared with control over morphology and Al2 O3 layer thicknesses ranging from sub-monolayer to a 4nm thick uniform coating. Dramatic changes in catalytic activity depending on the coverage and structure of Al2 O3 situated at the Pd/Al2 O3 interface are observed, with even a single monolayer of alumina contributing an order of magnitude increase in reaction rate. By building the Pd/Al2 O3 interface up layer-by-layer and using uniform Pd nanocrystals, this work demonstrates the importance of controlled and tunable materials in determining metal-support interactions and catalyst activity.

    View details for DOI 10.1002/adma.202104533

    View details for PubMedID 34535919

  • Composition and pressure effects on the structure, elastic properties and hardness of aluminoborosilicate glass JOURNAL OF NON-CRYSTALLINE SOLIDS Wu, J., Gross, T. M., Huang, L., Jaccani, S., Youngman, R. E., Rzoska, S. J., Bockowski, M., Bista, S., Stebbins, J. F., Smedskjaer, M. M. 2020; 530
  • Anionic speciation in sodium and potassium silicate glasses near the metasilicate ([Na,K]2SiO3) composition: 29Si, 17O, and 23Na NMR. J. Non-Cryst. Solids: X Stebbins, J. F. 2020; 6: 1000491-12
  • Tuning the bandgap of Cs2AgBiBr6 through dilute tin alloying. Chemical science Lindquist, K. P., Mack, S. A., Slavney, A. H., Leppert, L., Gold-Parker, A., Stebbins, J. F., Salleo, A., Toney, M. F., Neaton, J. B., Karunadasa, H. I. 2019; 10 (45): 10620-10628

    Abstract

    The promise of lead halide hybrid perovskites for optoelectronic applications makes finding less-toxic alternatives a priority. The double perovskite Cs2AgBiBr6 (1) represents one such alternative, offering long carrier lifetimes and greater stability under ambient conditions. However, the large and indirect 1.95 eV bandgap hinders its potential as a solar absorber. Here we report that alloying crystals of 1 with up to 1 atom% Sn results in a bandgap reduction of up to ca. 0.5 eV while maintaining low toxicity. Crystals can be alloyed with up to 1 atom% Sn and the predominant substitution pathway appears to be a ∼2 : 1 substitution of Sn2+ and Sn4+ for Ag+ and Bi3+, respectively, with Ag+ vacancies providing charge compensation. Spincoated films of 1 accommodate a higher Sn loading, up to 4 atom% Sn, where we see mostly Sn2+ substitution for both Ag+ and Bi3+. Density functional theory (DFT) calculations ascribe the bandgap redshift to the introduction of Sn impurity bands below the conduction band minimum of the host lattice. Using optical absorption spectroscopy, photothermal deflection spectroscopy, X-ray absorption spectroscopy, 119Sn NMR, redox titration, single-crystal and powder X-ray diffraction, multiple elemental analysis and imaging techniques, and DFT calculations, we provide a detailed analysis of the Sn content and oxidation state, dominant substitution sites, and charge-compensating defects in Sn-alloyed Cs2AgBiBr6 (1:Sn) crystals and films. An understanding of heterovalent alloying in halide double perovskites opens the door to a wider breadth of potential alloying agents for manipulating their band structures in a predictable manner.

    View details for DOI 10.1039/c9sc02581b

    View details for PubMedID 32110348

    View details for PubMedCentralID PMC7020786

  • Tuning the bandgap of Cs2AgBiBr6 through dilute tin alloying CHEMICAL SCIENCE Lindquist, K. P., Mack, S. A., Slavney, A. H., Leppert, L., Gold-Parker, A., Stebbins, J. F., Salleo, A., Toney, M. F., Neaton, J. B., Karunadasa, H. I. 2019; 10 (45): 10620–28

    View details for DOI 10.1039/c9sc02581b

    View details for Web of Science ID 000498611100018

  • Pentacoordinated and hexacoordinated silicon cations in a potassium silicate glass: Effects of pressure and temperature JOURNAL OF NON-CRYSTALLINE SOLIDS Stebbins, J. F., Bistal, S. 2019; 505: 234–40
  • Pentacoordinated silicon in ambient pressure potassium and lithium silicate glasses: temperature and compositional effects and analogies to alkali borate and germanate systems J. Non-Cryst. Solids: X Stebbins, J. F. 2019; 1: 100012-1-12
  • Toward the wider application of Si-29 NMR spectroscopy to paramagnetic transition metal silicate minerals and glasses: Fe(II), Co(II), and Ni(II) silicates AMERICAN MINERALOGIST Stebbins, J. F., McCarty, R. J., Palke, A. C. 2018; 103 (5): 776–91
  • NMR at high temperature Modern Methods in Solids State NMR: A Practitioner's Guide Stebbins, J. F. edited by Hodgkinson, P. 2018
  • Structural changes in calcium aluminoborosilicate glasses recovered from pressures of 1.5 to 3 GPa: Interactions of two network species with coordination number increases JOURNAL OF NON-CRYSTALLINE SOLIDS Bista, S., Stebbins, J. F., Wu, J., Gross, T. M. 2017; 478: 50–57
  • Toward the wider application of Si-29 NMR spectroscopy to paramagnetic transition metal silicate minerals: Copper(II) silicates AMERICAN MINERALOGIST Stebbins, J. F. 2017; 102 (12): 2406–14
  • Bond length-bond angle correlation in densified silica-Results from O-17 NMR spectroscopy JOURNAL OF CHEMICAL PHYSICS Trease, N. M., Clark, T. M., Grandinetti, P. J., Stebbins, J. F., Sen, S. 2017; 146 (18)

    View details for DOI 10.1063/1.4983041

    View details for Web of Science ID 000401368900027

  • Solid-state NMR and short-range order in crystalline oxides and silicates: a new tool in paramagnetic resonances. Acta crystallographica. Section C, Structural chemistry Stebbins, J. F., McCarty, R. J., Palke, A. C. 2017; 73: 128-136

    Abstract

    Most applications of high-resolution NMR to questions of short-range order/disorder in inorganic materials have been made in systems where ions with unpaired electron spins are of negligible concentration, with structural information extracted primarily from chemical shifts, quadrupolar coupling parameters, and nuclear dipolar couplings. In some cases, however, the often-large additional resonance shifts caused by interactions between unpaired electron and nuclear spins can provide unique new structural information in materials with contents of paramagnetic cations ranging from hundreds of ppm to several per cent and even higher. In this brief review we focus on recent work on silicate, phosphate, and oxide materials with relatively low concentrations of paramagnetic ions, where spectral resolution can remain high enough to distinguish interactions between NMR-observed nuclides and one or more magnetic neighbors in different bonding configurations in the first, second, and even farther cation shells. We illustrate the types of information available, some of the limitations of this approach, and the great prospects for future experimental and theoretical work in this field. We give examples for the effects of paramagnetic transition metal, lanthanide, and actinide cation substitutions in simple oxides, pyrochlore, zircon, monazite, olivine, garnet, pyrochlores, and olivine structures.

    View details for DOI 10.1107/S2053229616015606

    View details for PubMedID 28257006

  • Constraints on aluminum and scandium substitution mechanisms in forsterite, periclase, and larnite: high resolution NMR American Mineralogist McCarty, R. J., Stebbins, J. F. 2017; 102: 1244-1253
  • Multinuclear NMR investigation of temperature effects on structural reactions involving non-bridging oxygens in multicomponent oxide glasses JOURNAL OF NON-CRYSTALLINE SOLIDS Morin, E. I., Stebbins, J. F. 2017; 471: 179-186
  • The role of modifier cations in network modifier cation coordination increases with pressure in aluminosilicate glasses and melts from 1 to 3 GPa Am Mineral. Bista, S., Stebbins, J. 2017; 102: 1657-1666
  • Structural investigation of hydrous sodium borosilicate glasses j. Non-Cryst. Solids Bauer, U., Behrens, H., Reinsch, S., Morin, E. i., Stebbins, J. F. 2017; 465: 39-48
  • “Free” oxide ions in silicate melts: thermodynamic considerations and probable effects of temperature Chemical Geology Stebbins, J. F. 2017; 461: 2-12
  • Investigating lanthanide dopant distributions in Yttrium Aluminum Garnet (YAG) using solid state paramagnetic NMR. Solid state nuclear magnetic resonance McCarty, R. J., Stebbins, J. F. 2016; 79: 11-22

    Abstract

    This paper demonstrates the approach of using paramagnetic effects observed in NMR spectra to investigate the distribution of lanthanide dopant cations in YAG (yttrium aluminum garnet, Y3Al5O12) optical materials, as a complimentary technique to optical spectroscopy and other standard methods of characterization. We investigate the effects of Ce(3+), Nd(3+), Yb(3+), Tm(3+), and Tm(3+)-Cr(3+) on (27)Al and (89)Y NMR spectra. We note shifted resonances for both AlO4 and AlO6 sites. In some cases, multiple shifted peaks are observable, and some of these can be empirically assigned to dopant cations in known configurations to the observed nuclides. In many cases, AlO6 peaks shifted by more than one magnetic neighbor can be detected. In general, we observe that the measured intensities of shifted resonances, when spinning sidebands are included, are consistent with predictions from models with dopant cations that are randomly distributed throughout the lattice. In at least one set of (27)Al spectra, we identify two sub-peaks possibly resulting from two paramagnetic cations with magnetically coupled spin states neighboring the observed nucleus. We identify systematic changes in the spectra related to known parameters describing the magnetic effects of lanthanide cations, such as larger shift distances when the expectation value of electron spins is greater. We lastly comment on the promise of this technique in future analyses of laser and other crystalline oxide materials.

    View details for DOI 10.1016/j.ssnmr.2016.10.001

    View details for PubMedID 27794215

  • Network oxygen sites in calcium aluminoborosilicate glasses: Results from O-17{Al-27} and O-17{B-11} double resonance NMR JOURNAL OF NON-CRYSTALLINE SOLIDS LaComb, M., Rice, D., Stebbins, J. F. 2016; 447: 248-254
  • Detection of "free" oxide ions in low-silica Ca/Mg silicate glasses:. Results from O-17 -> Si-29 HETCOR NMR JOURNAL OF NON-CRYSTALLINE SOLIDS Hung, I., Gan, Z., Gor'kov, P. L., Kaseman, D. C., Sen, S., Lacomb, M., Stebbins, J. F. 2016; 445: 1-6
  • Transition Metal Dopant Cation Distributions in MgO and CaO: New Inferences from Paramagnetically Shifted Resonances in O-17, Mg-25, and Ca-43 NMR Spectra JOURNAL OF PHYSICAL CHEMISTRY C McCarty, R. J., Stebbins, J. F. 2016; 120 (20): 11111-11120
  • Order, disorder and mixing: The atomic structure of amorphous mixtures of titania and tantala JOURNAL OF NON-CRYSTALLINE SOLIDS Bassiri, R., Abernathy, M. R., Liou, F., Mehta, A., Gustafson, E. K., Hart, M. J., Isa, H. N., Kim, N., Lin, A. C., MacLaren, I., Martin, I. W., Route, R. K., Rowan, S., Shyam, B., Stebbins, J. F., Fejer, M. M. 2016; 438: 59-66
  • Glass structure, melt structure, and dynamics: Some concepts for petrology AMERICAN MINERALOGIST Stebbins, J. F. 2016; 101 (3-4): 753-768
  • Response of complex networks to compression: Ca, La, and Y aluminoborosilicate glasses formed from liquids at 1 to 3 GPa pressures. journal of chemical physics Bista, S., Morin, E. I., Stebbins, J. F. 2016; 144 (4): 044502-?

    Abstract

    Aluminoborosilicate glasses containing relatively high field strength modifiers (Ca, La, and Y) have been compressed at pressures up to 3 GPa and near the glass transition temperature (Tg) and quenched to room temperature at high pressure followed by decompression. Structural changes were quantified with high-resolution (27)Al and (11)B MAS nuclear magnetic resonance at 14.1-18.8 T. The changes with pressure in Al and B coordinations in the recovered samples are quite large with more than 50% decreases in tetrahedral aluminum ((IV)Al) and 200%-300% increases in tetrahedral boron ((IV)B). Glasses with higher field strength modifiers (La and Y) contain more high coordinated aluminum ((V,V I)Al) at all pressures studied. More high coordinated boron also correlates with higher field strength modifier if all three compositions are compared on an isothermal basis. Although lowering fictive temperature and increasing pressure both increase Al and B coordinations, our study shows that the actual mechanisms for structural changes are most probably different for temperature and pressure effects. Using a rough thermodynamic model to extrapolate to higher pressures, it appears that a simple non-bridging oxygen (NBO) consumption mechanism is not sufficient to convert all the aluminum to octahedral and boron to tetrahedral coordination, suggesting other mechanisms for structural changes could occur at high pressure as NBO becomes depleted.

    View details for DOI 10.1063/1.4940691

    View details for PubMedID 26827221

  • Separating the effects of composition and fictive temperature on Al and B coordination in Ca, La, Y aluminosilicate, aluminoborosilicate and aluminoborate glasses JOURNAL OF NON-CRYSTALLINE SOLIDS Morin, E. I., Stebbins, J. F. 2016; 432: 384-392
  • Structure of amorphous silica-hafnia and silica-zirconia thin-film materials: The role of a metastable equilibrium state in non-glass-forming oxide systems JOURNAL OF NON-CRYSTALLINE SOLIDS Kim, N., Bassiri, R., Fejer, M. M., Stebbins, J. F. 2015; 429: 5-12
  • Tricluster oxygen atoms in crystalline and glassy SrB4O7: High resolution B-11 and O-17 nuclear magnetic resonance analysis JOURNAL OF NON-CRYSTALLINE SOLIDS LaComb, M., Stebbins, J. F. 2015; 428: 105-111
  • Aluminosilicate melts and glasses at 1 to 3 GPa: Temperature and pressure effects on recovered structural and density changes AMERICAN MINERALOGIST Bista, S., Stebbins, J. F., Hankins, W. B., Sisson, T. W. 2015; 100 (10): 2298-2307
  • An investigation of local Fe2+ order-disorder in a mantle grospydite garnet using paramagnetically shifted Al-27 and Si-29 MAS NMR resonances EUROPEAN JOURNAL OF MINERALOGY Palke, A. C., Geiger, C. A., Stebbins, J. F. 2015; 27 (4): 463-470
  • Transition metal cation site preferences in forsterite (Mg2SiO4) determined from paramagnetically shifted NMR resonances AMERICAN MINERALOGIST McCarty, R. J., Palke, A. C., Stebbins, J. F., Hartman, J. S. 2015; 100 (5-6): 1265-1276
  • Order within disorder: The atomic structure of ion-beam sputtered amorphous tantala (a-Ta2O5) APL MATERIALS Bassiri, R., Liou, F., Abernathy, M. R., Lin, A. C., Kim, N., Mehta, A., Shyam, B., Byer, R. L., Gustafson, E. K., Hart, M., MacLaren, I., Martin, I. W., Route, R. K., Rowan, S., Stebbins, J. F., Fejer, M. M. 2015; 3 (3)

    View details for DOI 10.1063/1.4913586

    View details for Web of Science ID 000352450200004

  • Cation order-disorder in Fe-bearing pyrope and grossular garnets: A Al-27 and Si-29 MAS NMR and Fe-57 Mossbauer spectroscopy study AMERICAN MINERALOGIST Palke, A. C., Stebbins, J. F., Geiger, C. A., Tippelt, G. 2015; 100 (2-3): 536-547
  • The structure of ion beam sputtered amorphous alumina films and effects of Zn doping: High-resolution Al-27 NMR JOURNAL OF NON-CRYSTALLINE SOLIDS Kim, N., Bassiri, R., Fejer, M. M., Stebbins, J. F. 2014; 405: 1-6
  • Cation Field Strength Effects on Boron Coordination in Binary Borate Glasses JOURNAL OF THE AMERICAN CERAMIC SOCIETY Wu, J., Stebbins, J. F. 2014; 97 (9): 2794-2801

    View details for DOI 10.1111/jace.13100

    View details for Web of Science ID 000341826500017

  • Modifier cation (Ba, Ca, La, Y) field strength effects on aluminum and boron coordination in aluminoborosilicate glasses: the roles of fictive temperature and boron content APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING Morin, E. I., Wu, J., Stebbins, J. F. 2014; 116 (2): 479-490
  • NMR spectroscopy in inorganic Earth materials Spectroscopic Methods in Mineralogy and Materials Sciences Stebbins, J. F., Xue, X. edited by Henderson, G. S., Neuville, D., Downs, R. T. Mineralogical Society of America. 2014: 605–653
  • (31)P magic angle spinning NMR study of flux-grown rare-Earth element orthophosphate (monazite/xenotime) solid solutions: evidence of random cation distribution from paramagnetically shifted NMR resonances. Inorganic chemistry Palke, A. C., Stebbins, J. F., Boatner, L. A. 2013; 52 (21): 12605-12615

    Abstract

    We present (31)P magic angle spinning nuclear magnetic resonance spectra of flux-grown solid solutions of La(1-x)Ce(x)PO4 (x between 0.027 and 0.32) having the monoclinic monazite structure, and of Y(1-x)M(x)PO4 (M = V(n+), Ce(3+), Nd(3+), x between 0.001 and 0.014) having the tetragonal zircon structure. Paramagnetically shifted NMR resonances are observed in all samples due to the presence of paramagnetic V(n+), Ce(3+), and Nd(3+) in the diamagnetic LaPO4 or YPO4. As a first-order observation, the number and relative intensities of these peaks are related to the symmetry and structure of the diamagnetic host phase. The presence of paramagnetic shifts allows for increased resolution between NMR resonances for distinct atomic species which leads to the observation of low intensity peaks related to PO4 species having more than one paramagnetic neighbor two or four atomic bonds away. Through careful analysis of peak areas and comparison with predictions for simple models, it was determined that solid solutions in the systems examined here are characterized by complete disorder (random distribution) of diamagnetic La(3+) or Y(3+) with the paramagnetic substitutional species Ce(3+) and Nd(3+). The increased resolution given by the paramagnetic interactions also leads to the observation of splitting of specific resonances in the (31)P NMR spectra that may be caused by local, small-scale distortions from the substitution of ions having dissimilar ionic radii.

    View details for DOI 10.1021/ic401757z

    View details for PubMedID 24131129

  • Interaction between composition and temperature effects on non-bridging oxygen and high-coordinated aluminum in calcium aluminosilicate glasses AMERICAN MINERALOGIST Thompson, L. M., Stebbins, J. F. 2013; 98 (11-12): 1980-1987
  • Effects of annealing on the structure of ion beam sputtered amorphous tantalum oxide: Oxygen-17 NMR spectra and relaxation times JOURNAL OF NON-CRYSTALLINE SOLIDS Kim, N., Stebbins, J. F. 2013; 378: 158-162
  • Tunable plasticity in amorphous silicon carbide films. ACS applied materials & interfaces Matsuda, Y., Kim, N., King, S. W., Bielefeld, J., Stebbins, J. F., Dauskardt, R. H. 2013; 5 (16): 7950-7955

    Abstract

    Plasticity plays a crucial role in the mechanical behavior of engineering materials. For instance, energy dissipation during plastic deformation is vital to the sufficient fracture resistance of engineering materials. Thus, the lack of plasticity in brittle hybrid organic-inorganic glasses (hybrid glasses) often results in a low fracture resistance and has been a significant challenge for their integration and applications. Here, we demonstrate that hydrogenated amorphous silicon carbide films, a class of hybrid glasses, can exhibit a plasticity that is even tunable by controlling their molecular structure and thereby leads to an increased and adjustable fracture resistance in the films. We decouple the plasticity contribution from the fracture resistance of the films by estimating the "work-of-fracture" using a mean-field approach, which provides some insight into a potential connection between the onset of plasticity in the films and the well-known rigidity percolation threshold.

    View details for DOI 10.1021/am402046e

    View details for PubMedID 23876200

  • Interactions between network cation coordination and non-bridging oxygen abundance in oxide glasses and melts: Insights from NMR spectroscopy CHEMICAL GEOLOGY Stebbins, J. F., Wu, J., Thompson, L. M. 2013; 346: 34-46
  • Oxide ion speciation in potassium silicate glasses: New limits from O-17 NMR JOURNAL OF NON-CRYSTALLINE SOLIDS Stebbins, J. F., Sen, S. 2013; 368: 17-22
  • Temperature and modifier cation field strength effects on aluminoborosilicate glass network structure JOURNAL OF NON-CRYSTALLINE SOLIDS Wu, J., Stebbins, J. F. 2013; 362: 73-81
  • Challenges in Ceramic Science: A Report from the Workshop on Emerging Research Areas in Ceramic Science JOURNAL OF THE AMERICAN CERAMIC SOCIETY Rohrer, G. S., Affatigato, M., Backhaus, M., Bordia, R. K., Chan, H. M., Curtarolo, S., Demkov, A., Eckstein, J. N., Faber, K. T., Garay, J. E., Gogotsi, Y., Huang, L., Jones, L. E., Kalinin, S. V., Lad, R. J., Levi, C. G., Levy, J., Maria, J., Mattos, L., Navrotsky, A., Orlovskaya, N., Pantano, C., Stebbins, J. F., Sudarshan, T. S., Tani, T., Weil, K. S. 2012; 95 (12): 3699-3712

    View details for DOI 10.1111/jace.12033

    View details for Web of Science ID 000312145600001

  • Estimating accuracy of O-17 NMR measurements in oxide glasses: Constraints and evidence from crystalline and glassy calcium and barium silicates JOURNAL OF NON-CRYSTALLINE SOLIDS Thompson, L. M., McCarty, R. J., Stebbins, J. F. 2012; 358 (22): 2999-3006
  • Incorporation of Fe and Al in MgSiO3 perovskite: An investigation by Al-27 and Si-29 NMR spectroscopy AMERICAN MINERALOGIST Palke, A. C., Stebbins, J. F., Frost, D. J., McCammon, C. A. 2012; 97 (11-12): 1955-1964
  • Properties of impurity-bearing ferrihydrite I. Effects of Al content and precipitation rate on the structure of 2-line ferrihydrite GEOCHIMICA ET COSMOCHIMICA ACTA Cismasu, A. C., Michel, F. M., Stebbins, J. F., Levard, C., Brown, G. E. 2012; 92: 275-291
  • Non-stoichiometric non-bridging oxygens and five-coordinated aluminum in alkaline earth aluminosilicate glasses: Effect of modifier cation size JOURNAL OF NON-CRYSTALLINE SOLIDS Thompson, L. M., Stebbins, J. F. 2012; 358 (15): 1783-1789
  • Natural hydrous amorphous silica: Quantitation of network speciation and hydroxyl content by Si-29 MAS NMR and vibrational spectroscopy AMERICAN MINERALOGIST Chemtob, S. M., Rossman, G. R., Stebbins, J. F. 2012; 97 (1): 203-211
  • Quadrupolar NMR in the Earth Sciences NMR of Quadrupolar Nuclei in Solid Materials, and Encyclopedia of Magnetic Resonance (online publication) Stebbins, J. F. edited by Wasylishen, R. E., Ashbrook, S. E., Wimperis, S. John Wiley & Sons, Ltd.. 2012: 387–400
  • High-temperature in situ B-11 NMR study of network dynamics in boron-containing glass-forming liquids JOURNAL OF NON-CRYSTALLINE SOLIDS Wu, J., Potuzak, M., Stebbins, J. F. 2011; 357 (24): 3944-3951
  • Temperature calibration for high-temperature MAS NMR to 913 K: Cu-63 MAS NMR of CuBr and CuI, and Na-23 MAS NMR of NaNbO3 SOLID STATE NUCLEAR MAGNETIC RESONANCE Wu, J., Kim, N., Stebbins, J. F. 2011; 40 (2): 45-50

    Abstract

    The solid-state phase transitions of CuBr, CuI and NaNbO(3) can be readily observed using (63)Cu and (23)Na high-temperature magic-angle spinning nuclear magnetic resonance spectroscopy. Temperature has large, linear effects on the peak maximum of (63)Cu in each solid phase of CuBr and CuI, and there is large jump in shift across each phase transition. The (23)Na MAS NMR peak intensities and the line widths in NaNbO(3) also clearly show its high-temperature transition to the cubic phase. These data can be used to calibrate high-temperature MAS NMR probes up to 913 K, which is two hundred degrees higher than the commonly-used temperature calibration based on the chemical shift of (207)Pb in Pb(NO(3))(2).

    View details for DOI 10.1016/j.ssnmr.2011.04.004

    View details for Web of Science ID 000295020700003

    View details for PubMedID 21546224

  • Structure of Amorphous Tantalum Oxide and Titania-Doped Tantala: O-17 NMR Results for Sol-Gel and Ion-Beam-Sputtered Materials CHEMISTRY OF MATERIALS Kim, N., Stebbins, J. F. 2011; 23 (15): 3460-3465

    View details for DOI 10.1021/cm200630m

    View details for Web of Science ID 000293357100010

  • Paramagnetic interactions in the P-31 NMR spectroscopy of rare earth element orthophosphate (REPO4, monazite/xenotime) solid solutions AMERICAN MINERALOGIST Palke, A. C., Stebbins, J. F. 2011; 96 (8-9): 1343-1353
  • Variable-temperature Al-27 and Si-29 NMR studies of synthetic forsterite and Fe-bearing Dora Maira pyrope garnet: Temperature dependence and mechanisms of paramagnetically shifted peaks AMERICAN MINERALOGIST Palke, A. C., Stebbins, J. F. 2011; 96 (7): 1090-1099
  • Raman, Brillouin, and nuclear magnetic resonance spectroscopic studies on shocked borosilicate glass JOURNAL OF APPLIED PHYSICS Manghnani, M. H., Hushur, A., Sekine, T., Wu, J., Stebbins, J. F., Williams, Q. 2011; 109 (11)

    View details for DOI 10.1063/1.3592346

    View details for Web of Science ID 000292214700030

  • Non-bridging oxygen and high-coordinated aluminum in metaluminous and peraluminous calcium and potassium aluminosilicate glasses: High-resolution O-17 and Al-27 MAS NMR results AMERICAN MINERALOGIST Thompson, L. M., Stebbins, J. F. 2011; 96 (5-6): 841-853
  • Quench rate and temperature effects on boron coordination in aluminoborosilicate melts JOURNAL OF NON-CRYSTALLINE SOLIDS Wu, J., Stebbins, J. F. 2010; 356 (41-42): 2097-2108
  • Silicon coordination in rutile and TiO2-II at ambient and high pressures: Si-29 NMR AMERICAN MINERALOGIST Mosenfelder, J. L., Kim, N., Stebbins, J. F. 2010; 95 (7): 968-973
  • Probing the electrical properties of highly-doped Al:ZnO nanowire ensembles JOURNAL OF APPLIED PHYSICS Noriega, R., Rivnay, J., Goris, L., Kaelblein, D., Klauk, H., Kern, K., Thompson, L. M., Palke, A. C., Stebbins, J. F., Jokisaari, J. R., Kusinski, G., Salleo, A. 2010; 107 (7)

    View details for DOI 10.1063/1.3360930

    View details for Web of Science ID 000276795400081

  • Effects of e-beam curing on glass structure and mechanical properties of nanoporous organosilicate thin films INTERNATIONAL JOURNAL OF MATERIALS RESEARCH Gage, D. M., Peng, L., Stebbins, J., Yim, K. S., Al-Bayati, A., Demos, A., Dauskardt, R. H. 2010; 101 (2): 228-235

    View details for DOI 10.3139/146.110275

    View details for Web of Science ID 000275653100008

  • Structural response of a highly viscous aluminoborosilicate melt to isotropic and anisotropic compressions JOURNAL OF CHEMICAL PHYSICS Wu, J., Deubener, J., Stebbins, J. F., Grygarova, L., Behrens, H., Wondraczek, L., Yue, Y. 2009; 131 (10)

    View details for DOI 10.1063/1.3223282

    View details for Web of Science ID 000269814800030

  • Simultaneous aluminum, silicon, and sodium coordination changes in 6 GPa sodium aluminosilicate glasses AMERICAN MINERALOGIST Kelsey, K. E., Stebbins, J. F., Mosenfelder, J. L., Asimow, P. D. 2009; 94 (8-9): 1205-1215
  • Cation field strength effects on high pressure aluminosilicate glass structure: Multinuclear NMR and La XAFS results GEOCHIMICA ET COSMOCHIMICA ACTA Kelsey, K. E., Stebbins, J. F., Singer, D. M., Brown, G. E., Mosenfelder, J. L., Asimow, P. D. 2009; 73 (13): 3914-3933
  • Forsterite, hydrous and anhydrous wadsleyite and ringwoodite (Mg2SiO4): Si-29 NMR results for chemical shift anisotropy, spin-lattice relaxation, and mechanism of hydration AMERICAN MINERALOGIST Stebbins, J. F., Smyth, J. R., Panero, W. R., Frost, D. J. 2009; 94 (7): 905-915
  • Confirmation of octahedrally coordinated phosphorus in AlPO4-containing stishovite by P-31 NMR EUROPEAN JOURNAL OF MINERALOGY Stebbins, J. F., Kim, N., Brunet, F., Irifune, T. 2009; 21 (4): 667-671
  • Effects of cation field strength on the structure of aluminoborosilicate glasses: High-resolution B-11, Al-27 and Na-23 MAS NMR JOURNAL OF NON-CRYSTALLINE SOLIDS Wu, J., Stebbins, J. F. 2009; 355 (9): 556-562
  • Forsterite, wadsleyite, and ringwoodite (Mg2SiO4): Si-29 NMR constraints on structural disorder and effects of paramagnetic impurity ions AMERICAN MINERALOGIST Stebbins, J. F., Panero, W. R., Smyth, J. R., Frost, D. J. 2009; 94 (4): 626-629
  • Effects of the degree of polymerization on the structure of sodium silicate and aluminosilicate glasses and melts: An O-17 NMR study GEOCHIMICA ET COSMOCHIMICA ACTA Lee, S. K., Stebbins, J. F. 2009; 73 (4): 1109-1119
  • Sc-2(WO4)(3) and Sc-2(MoO4)(3) and Their Solid Solutions: Sc-45, O-17, and Al-27 MAS NMR Results at Ambient and High Temperature CHEMISTRY OF MATERIALS Kim, N., Stebbins, J. F. 2009; 21 (2): 309-315

    View details for DOI 10.1021/cm8024632

    View details for Web of Science ID 000262605200019

  • Anomalous resonances in Si-29 and Al-27 NMR spectra of pyrope ([Mg,Fe](3)Al2Si3O12) garnets: effects of paramagnetic cations PHYSICAL CHEMISTRY CHEMICAL PHYSICS Stebbins, J. F., Kelsey, K. E. 2009; 11 (32): 6906-6917

    Abstract

    In oxide and silicate materials, particularly naturally-occurring minerals with contents of iron oxides greater than a few percent, paramagnetic impurities are well-known to broaden MAS NMR peaks, decrease relaxation times, and even cause overall loss of signal intensity. However, detection of resolved, discrete peaks that are shifted in frequency by nearby unpaired electron spins is rare in such systems. We report here high-resolution (27)Al and (29)Si spectra for synthetic and natural samples of pyrope garnet ([Mg,Fe](3)Al(2)Si(3)O(12)), the latter containing up to 3.5 wt% FeO. For both nuclides, spectra contain anomalous NMR peaks at frequencies that are 25 to 200 ppm from normal ranges, possibly through pseudocontact shifts induced by paramagnetic cations. Quantitation of peak areas suggests that signals from nuclides with such cations in their first shell may be broadened enough to be unobservable, while those with paramagnetics in their second cation shells may be substantially shifted. Overall spin-lattice relaxation rates are greatly enhanced by such impurities, and shifted resonances relax much faster than the unshifted main peaks. A high symmetry crystal structure (in this case cubic), which limits the number of different cation-cation distances in each shell, combined with a relatively low (non-cubic) symmetry for the sites hosting the magnetic cations, may be needed to readily detect such features.

    View details for DOI 10.1039/b904731j

    View details for Web of Science ID 000268676700004

    View details for PubMedID 19652824

  • THE DIVERSITY OF NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY NATO Advanced Study Institute on Biophysics and the Challenges of Emerging Threats Liu, C. W., Alekseyev, V. Y., Allwardt, J. R., Bankovich, A. J., Cade-Menun, B. J., Davis, R. W., Du, L., Garcia, K. C., Herschlag, D., Khosla, C., Kraut, D. A., Li, Q., Null, B., Puglisi, J. D., Sigala, P. A., Stebbins, J. F., Varani, L. SPRINGER. 2009: 65–81
  • Characterization of Phase Separation and Thermal History Effects in Magnesium Silicate Glass Fibers by Nuclear Magnetic Resonance Spectroscopy JOURNAL OF THE AMERICAN CERAMIC SOCIETY Stebbins, J. F., Kim, N., Andrejcak, M. J., Boymel, P. M., Zoitos, B. K. 2009; 92 (1): 68-74
  • Temperature effects on the network structure of oxide melts and their consequences for configurational heat capacity CHEMICAL GEOLOGY Stebbins, J. F. 2008; 256 (3-4): 80-91
  • Ca-Mg mixing in aluminosilicate glasses: An investigation using O-17 MAS and 3QMAS and Al-27 MAS NMR JOURNAL OF NON-CRYSTALLINE SOLIDS Kelsey, K. E., Allwardt, J. R., Stebbins, J. F. 2008; 354 (40-41): 4644-4653
  • Effects of UV cure on glass structure and fracture properties of nanoporous carbon-doped oxide thin films JOURNAL OF APPLIED PHYSICS Gage, D. M., Stebbins, J. F., Peng, L., Cui, Z., Al-Bayati, A., MacWilliams, K. P., M'saad, H., Dauskardt, R. H. 2008; 104 (4)

    View details for DOI 10.1063/1.2968438

    View details for Web of Science ID 000259265100026

  • High resolution O-17 MAS and triple-quantum MAS NMR studies of gallosilicate glasses JOURNAL OF NON-CRYSTALLINE SOLIDS Peng, L., Stebbins, J. F. 2008; 354 (27): 3120-3128
  • Temperature effects on non-bridging oxygen and aluminum coordination number in calcium aluminosilicate glasses and melts GEOCHIMICA ET COSMOCHIMICA ACTA Stebbins, J. F., Dubinsky, E. V., Kanehashi, K., Kelsey, K. E. 2008; 72 (3): 910-925
  • Cation order/disorder behavior and crystal chemistry of pyrope-grossular garnets: An O-17 3QMAS and Al-27 MAS NMR spectroscopic study AMERICAN MINERALOGIST Kelsey, K. E., Stebbins, J. F., Du, L., Mosenfelder, J. L., Asimow, P. D., Geiger, C. A. 2008; 93 (1): 134-143
  • Structure, local environment, and ionic conductivity in scandia stabilized zirconia Solid State Ionics Huang, H., Hsieh, C. H., Kim, N., Stebbins, J. F., Prinz, F. 2008; 179: 1442-1445
  • Sodium germanate glasses and crystals: NMR constraints on variation in structure with composition JOURNAL OF NON-CRYSTALLINE SOLIDS Peng, L., Stebbins, J. F. 2007; 353 (52-54): 4732-4742
  • In situ high temperature Al-27 NMR study of structure and dynamics in a calcium aluminosilicate glass and melt JOURNAL OF NON-CRYSTALLINE SOLIDS Kanehashi, K., Stebbins, J. F. 2007; 353 (44-46): 4001-4010
  • Vacancy and cation distribution in yttria-doped ceria: An Y-89 and O-17 MAS NMR study CHEMISTRY OF MATERIALS Kim, N., Stebbins, J. F. 2007; 19 (23): 5742-5747

    View details for DOI 10.1021/cm0715388

    View details for Web of Science ID 000250803900038

  • High temperature O-17 MAS NMR study scandia and yttria stabilized of calcia, magnesia, zirconia SOLID STATE IONICS Kim, N., Hsieh, C., Huang, H., Prinz, F. B., Stebbins, J. F. 2007; 178 (27-28): 1499-1506
  • Scandium-45 NMR of pyrope-grossular garnets: Resolution of multiple scandium sites and comparison with X-ray diffraction and X-ray absorption spectroscopy AMERICAN MINERALOGIST Kim, N., Stebbins, J. F., Quartieri, S., Oberti, R. 2007; 92 (11-12): 1875-1880
  • Germanosilicate and alkali germanosilicate glass structure: New insights from high-resolution oxygen-17 NMR JOURNAL OF NON-CRYSTALLINE SOLIDS Du, L., Peng, L., Stebbins, J. F. 2007; 353 (30-31): 2910-2918
  • Effect of structural transitions on properties of high-pressure silicate melts: Al-27 NMR, glass densities, and melt viscosities AMERICAN MINERALOGIST Allwardt, J. R., Stebbins, J. F., Terasaki, H., Du, L., Frost, D. J., Withers, A. C., Hirschmann, M. M., Suzuki, A., Ohtani, E. 2007; 92 (7): 1093-1104
  • Aluminum substitution in rutile titanium dioxide: New constraints from high-resolution Al-27 NMR CHEMISTRY OF MATERIALS Stebbins, J. F. 2007; 19 (7): 1862-1869

    View details for DOI 10.1021/cm0629053

    View details for Web of Science ID 000245208100044

  • Constraining O-17 and Al-27 NMR spectra of high-pressure crystals and glasses: New data for jadeite, pyrope, grossular, and mullite AMERICAN MINERALOGIST Kelsey, K. E., Stebbins, J. F., Du, L., Hankins, B. 2007; 92 (1): 210-216
  • Effect of UV cure on adhesive and cohesive failure of low-k films: Implications for integration Advanced Metallization Conference 2006 Gage, D. M., Stebbins, J. F., Dauskardt, R. H. MATERIALS RESEARCH SOCIETY. 2007: 327–330
  • Glasses and melts: Linking geochemistry and materials science ELEMENTS Calas, G., Henderson, G. S., Stebbins, J. F. 2006; 2 (5): 265-268
  • The structure of silicate glasses and melts ELEMENTS Henderson, G. S., Calas, G., Stebbins, J. F. 2006; 2 (5): 269-273
  • Disorder and the extent of polymerization in calcium silicate and aluminosilicate glasses: O-17NMR results and quantum chemical molecular orbital calculations GEOCHIMICA ET COSMOCHIMICA ACTA Lee, S. K., Stebbins, J. F. 2006; 70 (16): 4275-4286
  • Scandium coordination in solid oxides and stabilized zirconia: Sc-45 NMR CHEMISTRY OF MATERIALS Kim, N., Hsieh, C., Stebbins, J. F. 2006; 18 (16): 3855-3859

    View details for DOI 10.1021/cm0605901

    View details for Web of Science ID 000239396900037

  • Oxygen sites and network coordination in sodium germanate glasses and crystals: High-resolution oxygen-17 and sodium-23 NMR JOURNAL OF PHYSICAL CHEMISTRY B Du, L., Stebbins, J. F. 2006; 110 (25): 12427-12437

    Abstract

    Sodium germanate glasses are well-studied materials in which, unlike silicates but analogous to borates, the major structural consequence of alkali addition is generally thought to involve a coordination number increase of the network-forming Ge cations. However, the nature of this change, in particular quantifying fractions of nonbridging oxygens and of five- and/or six-coordinated Ge, has remained unresolved. We present here high-resolution 17O results, including triple-quantum MAS NMR (3QMAS), on a series of crystalline model compounds that allow the definition of ranges of chemical shifts corresponding to oxygens bonded to various coordinations of Ge. These include quartz- and rutile-structured GeO2, Na4Ge9O20, Na2Ge4O9, and Na2GeO3 (germanium dioxide, sodium enneagermanate, sodium tetragermanate, and sodium metagermanate). 3QMAS spectra of Na-germanate glasses ranging from 0% to 27% Na2O clearly show the development of partially resolved peaks as alkali is added, corresponding to signals from nonbridging oxygens (in the highest Na glasses) and to oxygen bridging between one four-coordinated and one higher coordinated Ge. As in conventional models of this system, nonbridging oxygen contents are much lower than in corresponding silicates. Although we do not directly distinguish between five- and six-coordinated Ge, modeling of bridging oxygen populations and comparison with measured speciation suggest that substantial proportions of both species are likely to be present. High-field 23Na MAS NMR shows systematic decreases in mean Na-O bond distance and/or coordination number with increasing alkali content that can be compared with published results for high-temperature liquids. These results, as well as comparison of molar volumes of glasses and high-temperature liquids, suggest the possibility of significant temperature effects on liquid structure.

    View details for DOI 10.1021/jp0615510

    View details for Web of Science ID 000238446900033

    View details for PubMedID 16800569

  • Physics, chemistry and rheology of silicate melts and glasses - Preface CHEMICAL GEOLOGY Moretti, R., Richet, P., Stebbins, J. F. 2006; 229 (1-3): 1-1
  • Quench rate and temperature effects on framework ordering in aluminosilicate melts AMERICAN MINERALOGIST Dubinsky, E. V., Stebbins, J. F. 2006; 91 (5-6): 753-761
  • Aluminum substitution in stishovite and MgSiO3 perovskite: High-resolution Al-27 NMR AMERICAN MINERALOGIST Stebbins, J. F., Du, L. S., Kelsey, K., Kojitani, H., Akaogi, M., Ono, S. 2006; 91 (2-3): 337-343
  • The development of a rapid quenching device for the study of the dependence of glass structure on fictive temperature REVIEW OF SCIENTIFIC INSTRUMENTS Kiczenski, T. J., Stebbins, J. F. 2006; 77 (1)

    View details for DOI 10.1063/1.2162751

    View details for Web of Science ID 000234979400017

  • UV curing effects on glass structure and mechanical properties of organosilicate low-k thin films 9th International Interconnect Technology Conference (IITC) Gage, D. M., Guyer, E. P., Stebbins, J. F., Cui, Z., Al-Bayati, A., Demos, A., MacWilliams, K. P., Dauskardt, R. H. IEEE, ELECTRON DEVICES SOC & RELIABILITY GROUP. 2006: 149–151
  • The effect of fictive temperature on the structural environment of fluorine in silicate and aluminosilicate glasses JOURNAL OF THE AMERICAN CERAMIC SOCIETY Kiczenski, T. J., Stebbins, J. F. 2006; 89 (1): 57-64
  • The effect of fictive temperature on the structure of E-glass: A high resolution, multinuclear NMR study JOURNAL OF NON-CRYSTALLINE SOLIDS Kiczenski, T. J., Du, L. S., Stebbins, J. 2005; 351 (46-48): 3571-3578
  • Network connectivity in aluminoborosilicate glasses: A high-resolution B-11, Al-27 and O-17 NMR study JOURNAL OF NON-CRYSTALLINE SOLIDS Du, L. S., Stebbins, J. F. 2005; 351 (43-45): 3508-3520
  • The effect of fictive temperature on Al coordination in high-pressure (10 GPa) sodium aluminosilicate glasses AMERICAN MINERALOGIST Allwardt, J. R., Poe, B. T., Stebbins, J. F. 2005; 90 (8-9): 1453-1457
  • Aluminium coordination in natural silica glasses from the Libyan Desert (Egypt): high field NMR results 9th International Conference on the Structure of Non-Crystalline Materials (NCM9) Stebbins, J. F., Du, L. S., Pratesi, G. SOC GLASS TECHNOLOGY. 2005: 340–44
  • Aluminum coordination and the densification of high-pressure aluminosilicate glasses AMERICAN MINERALOGIST Allwardt, J. R., Stebbins, J. F., Schmidt, B. C., Frost, D. J., Withers, A. C., Hirschmann, M. M. 2005; 90 (7): 1218-1222
  • Site connectivities in sodium aluminoborate glasses: multinuclear and multiple quantum NMR results SOLID STATE NUCLEAR MAGNETIC RESONANCE Du, L. S., Stebbins, J. F. 2005; 27 (1-2): 37-49

    Abstract

    In a series of sodium aluminoborate glasses, we have applied triple-quantum magic-angle spinning (3QMAS) 17O NMR to obtain high-resolution information about the connections among various network structural units, to explore the mixing of aluminum and boron species. Oxygen-17 3QMAS spectra reveal changes in connectivities between AlO4 ([4]Al), AlO5 and AlO6 ([5,6]Al), BO3 ([3]B) and BO4 ([4]B) units, by quantifying populations of bridging oxygens such as Al-O-Al, Al-O-B and B-O-B and of non-bridging oxygens. Several linkages such as [4]Al-O-[4]Al and three-coordinated oxygen associated with [5,6]Al in Al-O-Al, [4]Al-O-[4]B, [4]Al-O-[3]B and [5,6]Al-O-[3]B in Al-O-B as well as [4]B-O-[3]B and [3]B-O-[3]B in B-O-B can be distinguished for the first time. The fractions of these linkages were calculated from models of random mixing and of mixing with maximum avoidance of tetrahedral-tetrahedral linkages. The results suggest that the structure of all of glasses in this study is well approximated by the latter model. However, the energetic "penalty" for formation of [4]Al-O-[4]B may be somewhat less than for [4]Al-O-[4]Al and [4]B-O-[4]B. In general, the new results presented here are similar to those obtained on glasses in this system by 27Al{11B} REDOR NMR (J. Phys. Chem. B 104 (2000) 6541), but provide considerably more detail on network connectivity and ordering schemes.

    View details for DOI 10.1016/j.ssnmer.2004.08.003

    View details for Web of Science ID 000225955000007

    View details for PubMedID 15589726

  • The effect of composition, compression, and decompression on the structure of high pressure aluminosilicate glasses: an investigation utilizing 17O and 27Al NMR Frontiers of High Pressure Research Allwardt, J. R., Stebbins, J. F., Schmidt, B. C., Frost, D. J. edited by Chen, J., Wang, Y., Duffy, T. S., Shen, G., Dobrzhinetskaya, L. F. Elsevier, Amsterdam. 2005: 211–240
  • Structural mechanisms of compression and decompression in high-pressure K2Si4O9 glasses: an investigation utilizing Raman and NMR spectroscopy of glasses and crystalline materials CHEMICAL GEOLOGY Allwardt, J. R., Schmidt, B. C., Stebbins, J. F. 2004; 213 (1-3): 137-151
  • Correlated structural distributions in silica glass PHYSICAL REVIEW B Clark, T. M., Grandinetti, P. J., Florian, P., Stebbins, J. F. 2004; 70 (6)
  • F-19NMR study of the ordering of high field strength cations at fluoride sites in silicate and aluminosilicate glasses JOURNAL OF NON-CRYSTALLINE SOLIDS Kiczenski, T. J., Du, L. S., Stebbins, J. F. 2004; 337 (2): 142-149
  • Pressure-induced structural changes in a borosilicate glass-forming liquid: boron coordination, non-bridging oxygens, and network ordering JOURNAL OF NON-CRYSTALLINE SOLIDS Du, L. S., Allwardt, J. R., Schmidt, B. C., Stebbins, J. F. 2004; 337 (2): 196-200
  • Ca-Mg and K-Mg mixing around non-bridging O atoms in silicate glasses: An investigation using O-17 MAS and 3QMAS NMR AMERICAN MINERALOGIST Allwardt, J. R., Stebbins, J. F. 2004; 89 (5-6): 777-784
  • Calcium and strontium hexaluminates: NMR evidence that "pentacoordinate" cation sites are four-coordinated JOURNAL OF PHYSICAL CHEMISTRY B Du, L. S., Stebbins, J. F. 2004; 108 (12): 3681-3685

    View details for DOI 10.1021/jp037615d

    View details for Web of Science ID 000220323500001

  • Thermodynamic properties of analcime solid solutions AMERICAN JOURNAL OF SCIENCE Neuhoff, P. S., Hovis, G. L., Balassone, G., Stebbins, J. F. 2004; 304 (1): 21-66
  • Structure of Cl-containing silicate and aluminosilicate glasses; a 35Cl MAS-NMR study Geochimica et Cosmochimica Acta Sandland, T. O., Du, L.-S., Stebbins, J. F., Webster, J. D. 2004; 68: 5059-5069
  • Site preference and Si/B mixing in mixed-alkali borosilicate glasses: A high-resolution B-11 and O-17 NMR study CHEMISTRY OF MATERIALS Du, L. S., Stebbins, J. F. 2003; 15 (20): 3913-3921

    View details for DOI 10.1021/cm034427r

    View details for Web of Science ID 000185747100028

  • Nature of silicon-boron mixing in sodium borosilicate glasses: A high-resolution B-11 and O-17 NMR study JOURNAL OF PHYSICAL CHEMISTRY B Du, L. S., Stebbins, J. F. 2003; 107 (37): 10063-10076

    View details for DOI 10.1021/jp0340481

    View details for Web of Science ID 000185345400019

  • O-17 and Al-27 MAS and 3QMAS NMR study of synthetic and natural layer silicates CHEMISTRY OF MATERIALS Lee, S. K., Stebbins, J. F., Weiss, C. A., Kirkpatrick, R. J. 2003; 15 (13): 2605-2613

    View details for DOI 10.1021/cm030165h

    View details for Web of Science ID 000183810600017

  • Bonding preferences of non-bridging O atoms: Evidence from O-17 MAS and 3QMAS NMR on calcium aluminate and low-silica Ca-aluminosilicate glasses AMERICAN MINERALOGIST Allwardt, J. R., Lee, S. K., Stebbins, J. F. 2003; 88 (7): 949-954
  • Aluminum substitution in MgSiO3 perovskite: Investigation of multiple mechanisms by Al-27 NMR AMERICAN MINERALOGIST Stebbins, J. F., Kojitani, H., Akaogi, M., NAVROTSKY, A. 2003; 88 (7): 1161-1164
  • The distribution of sodium ions in aluminosilicate glasses: A high-field Na-23 MAS and 3Q MAS NMR study GEOCHIMICA ET COSMOCHIMICA ACTA Lee, S. K., Stebbins, J. F. 2003; 67 (9): 1699-1709
  • Nature of cation mixing and ordering in Na-Ca silicate glasses and melts JOURNAL OF PHYSICAL CHEMISTRY B Lee, S. K., Stebbins, J. F. 2003; 107 (14): 3141-3148

    View details for DOI 10.1021/jp027489y

    View details for Web of Science ID 000182037800009

  • O atom sites in natural kaolinite and muscovite: O-17 MAS and 3QMAS NMR study AMERICAN MINERALOGIST Lee, S. K., Stebbins, J. F. 2003; 88 (4): 493-500
  • Si-Al disorder and solid solutions in analcime, chabazite, and wairakite AMERICAN MINERALOGIST Neuhoff, P. S., Stebbins, J. F., Bird, D. K. 2003; 88 (2-3): 410-423
  • Solid-state NMR study of metastable immiscibility in alkali borosilicate glasses JOURNAL OF NON-CRYSTALLINE SOLIDS Du, L. S., Stebbins, J. F. 2003; 315 (3): 239-255
  • Order/disorder in natrolite group zeolites: A Si-29 and Al-27 MAS NMR study AMERICAN MINERALOGIST Neuhoff, P. S., Kroeker, S., Du, L. S., Fridriksson, T., Stebbins, J. F. 2002; 87 (10): 1307-1320
  • Effect of extraframework species on O-17 NMR chemical shifts in zeolite A MICROPOROUS AND MESOPOROUS MATERIALS Neuhoff, P. S., Shao, P., Stebbins, J. F. 2002; 55 (3): 239-251
  • Dynamics in ceramics SCIENCE Stebbins, J. F. 2002; 297 (5585): 1285-1287
  • Materials science. Dynamics in ceramics. Science (New York, N.Y.) Stebbins, J. F. 2002; 297 (5585): 1285-7

    View details for DOI 10.1126/science.1075881

    View details for PubMedID 12193772

  • Fluorine sites in calcium and barium oxyfluorides: F-19NMR on crystalline model compounds and glasses JOURNAL OF NON-CRYSTALLINE SOLIDS Kiczenski, T. J., Stebbins, J. F. 2002; 306 (2): 160-168
  • Disordering during melting: An O-17 NMR study of crystalline and glassy CaTiSiO5 (titanite) AMERICAN MINERALOGIST Kroeker, S., Rice, D., Stebbins, J. F. 2002; 87 (4): 572-579
  • New opportunities for high-resolution solid-state NMR spectroscopy of oxide materials at 21.1-and 18.8-t fields SOLID STATE NUCLEAR MAGNETIC RESONANCE Stebbins, J. F., Du, L. S., Kroeker, S., Neuhoff, P., Rice, D., Frye, J., Jakobsen, H. J. 2002; 21 (1-2): 105-115

    Abstract

    We present here high-resolution solid state NMR spectra of several oxide and silicate materials that illustrate the improvements obtainable with very high external fields (18.8 and 21.1 T), with probes capable of tuning to a wide frequency range that allow observations of nuclides from high to low magnetogyric ratio. We discuss 27Al MAS spectra for the zeolite scolecite (CaAl2Si3O10 x 3H2O), 17O MAS data for analcime (NaAlSi2O6 x H2O), calcium monoaluminate (CaAI2O4), and titanite (CaTiSiO5), 39K spin-echo spectra for leucite (KAlSi2O6), microline (KAlSiO8), muscovite (KAl2(AlSi3O10)(OH2) and a potassium aluminosolicate glass, and preliminary 73Ge spin-echo MAS spectra for crystalline and glassy germanium dioxide (GeO2).

    View details for DOI 10.1006/snmr.2001.0051

    View details for Web of Science ID 000174305700008

    View details for PubMedID 11949814

  • Chloride ion sites in silicate and aluminosilicate glasses: A preliminary study by Cl-35 solid-state NMR AMERICAN MINERALOGIST Stebbins, J. F., Du, L. S. 2002; 87 (2-3): 359-363
  • Oxygen sites in hydrous aluminosilicate glasses: The role of Al-O-Al and H2O GEOCHIMICA ET COSMOCHIMICA ACTA Oglesby, J. V., Zhao, P. D., Stebbins, J. F. 2002; 66 (2): 291-301
  • Extent of intermixing among framework units in silicate glasses and melts GEOCHIMICA ET COSMOCHIMICA ACTA Lee, S. K., Stebbins, J. F. 2002; 66 (2): 303-309
  • Topological disorder and reactivity of borosilicate glasses: Quantum chemical calculations and O-17 and B-11 NMR study JOURNAL OF PHYSICAL CHEMISTRY B Lee, S. K., Musgrave, C. B., Zhao, P. D., Stebbins, J. F. 2001; 105 (50): 12583-12595

    View details for DOI 10.1021/jp012119f

    View details for Web of Science ID 000172945700022

  • An O-17 NMR investigation of crystalline sodium metasilicate: Implications for the determination of local structure in alkali silicates JOURNAL OF PHYSICAL CHEMISTRY B Clark, T. M., Grandinetti, P. J., Florian, P., Stebbins, J. F. 2001; 105 (49): 12257-12265
  • Three-coordinated boron-11 chemical shifts in borates INORGANIC CHEMISTRY Kroeker, S., Stebbins, J. F. 2001; 40 (24): 6239-6246

    Abstract

    Despite the importance of (11)B nuclear magnetic resonance (NMR) in structural studies of borate glasses, no clear means of correlating NMR parameters with the number of nonbridging oxygens on three-coordinate boron has been demonstrated. In this work, a series of anhydrous, polycrystalline, binary borates has been examined by (11)B magic-angle spinning (MAS) NMR to obtain precise measurements of their three-coordinate boron isotropic chemical shifts. The shifts generally increase with the replacement of bridging oxygens by nonbridging oxygens, ranging from 14.6 ppm in crystalline B(2)O(3) to 22.5 ppm in magnesium orthoborate. The underlying physical basis for this trend is satisfactorily accounted for by considering second neighbor effects using bond valence sums. These data are supportive of a structural model for B(2)O(3) glass in which 72% of the boron atoms are in rings. High-field MAS NMR experiments (B(0) = 18.8 T) indicate that the boron shielding is anisotropic, with greater anisotropy measured for three-coordinate borons possessing one or two nonbridging oxygens, than for those with zero or three nonbridging oxygens.

    View details for Web of Science ID 000172181400023

    View details for PubMedID 11703125

  • A solid solution model for Si-Al substitution in disordered FAU and LTA zeolites MICROPOROUS AND MESOPOROUS MATERIALS Neuhoff, P. S., Stebbins, J. F. 2001; 49 (1-3): 139-148
  • Oxygen triclusters in crystalline CaAl4O7 (grossite) and in calcium aluminosilicate glasses: O-17 NMR AMERICAN MINERALOGIST Stebbins, J. F., Oglesby, J. V., Kroeker, S. 2001; 86 (10): 1307-1311
  • Comparison of FAM mixing to single-pulse mixing in O-17 3Q-and 5Q-MAS NMR of oxygen sites in zeolites CHEMICAL PHYSICS LETTERS Zhao, P., Neuhoff, P. S., Stebbins, J. F. 2001; 344 (3-4): 325-332
  • Hydroxyl-contents and hydroxyl-related concentration quenching in erbium-doped aluminophosphate, aluminosilicate and fluorosilicate glasses JOURNAL OF NON-CRYSTALLINE SOLIDS Houde-Walter, S. N., Peters, P. M., Stebbins, J. F., Zeng, Q. 2001; 286 (1-2): 118-131
  • Potassium hydrogen disilicate: A possible model compound for O-17 NMR spectra of hydrous silicate glasses AMERICAN MINERALOGIST Oglesby, J. V., Kroeker, S., Stebbins, J. F. 2001; 86 (3): 341-347
  • The mechanism of solution of aluminum oxide in MgSiO3 perovskite GEOPHYSICAL RESEARCH LETTERS Stebbins, J. F., Kroeker, S., Andrault, D. 2001; 28 (4): 615-618
  • Oxygen sites in silicate glasses: a new view from oxygen-17 NMR Chem. Geol. Stebbins, J. F., Oglesby, J. V., Lee, S. K. 2001; 174: 63-75
  • Direct observation of multiple oxygen sites in oxide glasses: recent advances from triple-quantum magic-angle spinning nuclear magnetic resonance Journal of Non-Crystalline Solids Stebbins, J., Zhao, P., Lee, S. K., Oglesby, J. V. 2001; 293: 67-73
  • Enhanced resolution and quantitation from “ultrahigh” field NMR spectroscopy of glasses J. Non-Cryst. Solids Kroeker, S., Neuhoff, P. S., Stebbins, J. F. 2001; 293: 440-445
  • NMR studies of oxide glass structure Solid State NMR: Theory and Applications Stebbins, J. F. edited by Duer, M. Blackwell Scientific, Oxford. 2001: 391–436
  • Magnesium coordination environments in glasses and minerals: New insight from high-field magnesium-25 MAS NMR AMERICAN MINERALOGIST Kroeker, S., Stebbins, J. F. 2000; 85 (10): 1459-1464
  • Non-bridging oxygen sites in barium borosilicate glasses: results from B-11 and O-17 NMR JOURNAL OF NON-CRYSTALLINE SOLIDS Zhao, P. D., Kroeker, S., Stebbins, J. F. 2000; 276 (1-3): 122-131
  • Quantification of five- and six-coordinated aluminum ions in aluminosilicate and fluoride-containing glasses by high-field, high-resolution Al-27 NMR JOURNAL OF NON-CRYSTALLINE SOLIDS Stebbins, J. F., Kroeker, S., Lee, S. K., Kiczenski, T. J. 2000; 275 (1-2): 1-6
  • Solid state NMR study of oxygen site exchange and Al-O-Al site concentration in analcime AMERICAN MINERALOGIST Cheng, X., Zhao, P. D., Stebbins, J. F. 2000; 85 (7-8): 1030-1037
  • The structure of aluminosilicate glasses: High-resolution O-17 and Al-27 MAS and 3QMAS JOURNAL OF PHYSICAL CHEMISTRY B Lee, S. K., Stebbins, J. F. 2000; 104 (17): 4091-4100
  • Al-O-Al and Si-O-Si sites in framework aluminosilicate glasses with Si/Al=1: quantification of framework disorder JOURNAL OF NON-CRYSTALLINE SOLIDS Lee, S. K., Stebbins, J. F. 2000; 270 (1-3): 260-264
  • Fluoride sites in aluminosilicate glasses: High-resolution F-19 NMR results AMERICAN MINERALOGIST Zeng, Q., Stebbins, J. F. 2000; 85 (5-6): 863-867
  • Si-29 CPMAS NMR investigations of silanol-group minerals and hydrous aluminosilicate glasses AMERICAN MINERALOGIST Oglesby, J. V., Stebbins, J. F. 2000; 85 (5-6): 722-731
  • Cation ordering at fluoride sites in silicate glasses: a high-resolution F-19 NMR study JOURNAL OF NON-CRYSTALLINE SOLIDS Stebbins, J. F., Zeng, Q. 2000; 262 (1-3): 1-5
  • Non-Bridging Oxygens in Borate Glasses: Characterization by 11B and 17O MAS and 3QMAS NMR Journal of Non-Crystalline Solids Stebbins, J. F., Zhao, P., Kroeker, S. 2000; 276: 9-19
  • Hydrogen speciation in hydrogen-loaded, germania-doped silica glass: a combined NMR and FTIR study of the effects of UV irradiation and heat treatment JOURNAL OF NON-CRYSTALLINE SOLIDS Zeng, Q., Stebbins, J. F., Heaney, A. D., Erdogan, T. 1999; 258 (1-3): 78-91
  • Reactive Al-O-Al sites in a natural zeolite: Triple-quantum oxygen-17 nuclear magnetic resonance AMERICAN MINERALOGIST Stebbins, J. F., Zhao, P. D., Lee, S. K., Cheng, X. 1999; 84 (10): 1680-1684
  • Pentacoordinate silicon in high-pressure crystalline and glassy phases of calcium disilicate (CaSi2O5) GEOPHYSICAL RESEARCH LETTERS Stebbins, J. F., Poe, B. T. 1999; 26 (16): 2521-2523
  • Multiple-quantum magic-angle spinning O-17 NMR studies of borate, borosilicate, and boroaluminate classes JOURNAL OF THE AMERICAN CERAMIC SOCIETY Wang, S. H., Stebbins, J. F. 1999; 82 (6): 1519-1528
  • The degree of aluminum avoidance in aluminosilicate glasses AMERICAN MINERALOGIST Lee, S. K., Stebbins, J. F. 1999; 84 (5-6): 937-945
  • Al-O-Al oxygen sites in crystalline aluminates and aluminosilicate glasses: High-resolution oxygen-17 NMR results AMERICAN MINERALOGIST Stebbins, J. F., Lee, S. K., Oglesby, J. V. 1999; 84 (5-6): 983-986
  • Cation clustering and formation of free oxide ions in sodium and potassium lanthanum silicate glasses: nuclear magnetic resonance and Raman spectroscopic findings JOURNAL OF NON-CRYSTALLINE SOLIDS Schaller, T., Stebbins, J. F., Wilding, M. C. 1999; 243 (2-3): 146-157
  • The structural role of lanthanum and yttrium in aluminosilicate glasses: A Al-27 and O-17 MAS NMR study JOURNAL OF PHYSICAL CHEMISTRY B Schaller, T., Stebbins, J. F. 1998; 102 (52): 10690-10697
  • Cation dynamics and premelting in lithium metasilicate (Li2SiO3) and sodium metasilicate (Na2SiO3): A high-temperature NMR study AMERICAN MINERALOGIST George, A. M., Richet, P., Stebbins, J. F. 1998; 83 (11-12): 1277-1284
  • Shocked quartz: A Si-29 magic-angle-spinning nuclear magnetic resonance study AMERICAN MINERALOGIST Fiske, P. S., Nellis, W. J., Xu, Z., Stebbins, J. F. 1998; 83 (11-12): 1285-1292
  • Fast rotational reorientation of NO3- ions and its relation to the glass transition in Ca0.4K0.6(NO3)(1.4) liquid: A N-15 NMR spin-lattice-relaxation study PHYSICAL REVIEW B Sen, S., Stebbins, J. F. 1998; 58 (13): 8379-8383
  • Oxygen speciation in hydrous silicate glasses: An oxygen-17 NMR study JOURNAL OF THE AMERICAN CHEMICAL SOCIETY Xu, Z., Maekawa, H., Oglesby, J. V., Stebbins, J. F. 1998; 120 (38): 9894-9901
  • Cation sites in mixed-alkali oxide glasses: correlations of NMR chemical shift data with site size and bond distance SOLID STATE IONICS Stebbins, J. F. 1998; 112 (1-2): 137-141
  • Structure and dynamics of magnesium in silicate melts: A high-temperature Mg-25 NMR study AMERICAN MINERALOGIST George, A. M., Stebbins, J. F. 1998; 83 (9-10): 1022-1029
  • On the structure of borosilicate glasses: a triple-quantum magic-angle spinning O-17 nuclear magnetic resonance study JOURNAL OF NON-CRYSTALLINE SOLIDS Wang, S. H., Stebbins, J. F. 1998; 231 (3): 286-290
  • Oxygen sites in the zeolite stilbite: a comparison of static, MAS, VAS, DAS and triple quantum MAS NMR techniques SOLID STATE NUCLEAR MAGNETIC RESONANCE Xu, Z., Stebbins, J. F. 1998; 11 (3-4): 243-251

    Abstract

    Static, magic angle spinning (MAS), variable angle spinning (VAS), dynamic angle spinning (DAS) and triple quantum magic angle spinning (3QMAS) NMR techniques were applied to separate and quantify oxygen signals from Al-O-Si and Si-O-Si sites of 17O-enriched samples of the mineral stilbite, a natural zeolite. DAS experiments showed that there was a distribution of quadrupolar coupling constants, asymmetry parameters and isotropic chemical shifts. Two methods were used to study the quantification problem of DAS and 3QMAS. Our results showed that DAS was quantitative. In 3QMAS, signal intensity from sites with larger quadrupolar coupling constants was reduced because of less efficient excitation. All techniques have shown a clear difference in rates of exchange between the two types of sites with interchannel H2O molecules.

    View details for Web of Science ID 000074865600012

    View details for PubMedID 9694393

  • Oxygen site exchange kinetics observed with solid state NMR in a natural zeolite GEOCHIMICA ET COSMOCHIMICA ACTA Xu, Z., Stebbins, J. F. 1998; 62 (10): 1803-1809
  • Temperature dependent structural changes in borate, borosilicate and boroaluminate liquids: high-resolution B-11, Si-29 and Al-27 NMR studies JOURNAL OF NON-CRYSTALLINE SOLIDS Sen, S., Xu, Z., Stebbins, J. F. 1998; 226 (1-2): 29-40
  • Phase relations in Na2O-SiO2 and K2Si4O9 systems up to 14 GPa and Si-29 NMR study of the new high-pressure phases: implications to the structure of high-pressure silicate glasses International Symposium on Role of Magmas on the Evolution of the Earth Kanzaki, M., Xue, X. Y., Stebbins, J. F. ELSEVIER SCIENCE BV. 1998: 9–21
  • Microscopic dynamics and viscous flow in a borosilicate glass-forming liquid JOURNAL OF NON-CRYSTALLINE SOLIDS Stebbins, J. F., Sen, S. 1998; 224 (1): 80-85
  • Na-23 chemical shifts and local structure in crystalline, glassy, and molten sodium borates and germanates SOLID STATE NUCLEAR MAGNETIC RESONANCE George, A. M., Sen, S., Stebbins, J. F. 1997; 10 (1-2): 9-17

    Abstract

    A simple correlation between average Na-O bond length and 23Na isotropic chemical shift in crystalline germanates and borates has been established, similar to existing correlations for sodium in silicates and carbonates. This empirical trend is discussed in terms of a decreasing paramagnetic contribution to the chemical shift with increasing average bond length. The correlation is then applied to data for sodium borate and germanate glasses and melts from room temperature to 1200 degrees C, where both structural and compositional effects on the chemical shift are apparent.

    View details for PubMedID 9472786

  • NMR evidence for excess non-bridging oxygen in an aluminosilicate glass NATURE Stebbins, J. F., Xu, Z. 1997; 390 (6655): 60-62
  • Disorder among network-modifier cations in silicate glasses: New constraints from triple-quantum O-17 NMR AMERICAN MINERALOGIST Stebbins, J. F., Oglesby, J. V., Xu, Z. 1997; 82 (11-12): 1116-1124
  • Anionic species determination in CaSiO3 glass using two-dimensional Si-29 NMR JOURNAL OF PHYSICAL CHEMISTRY B Zhang, P., Grandinetti, P. J., Stebbins, J. F. 1997; 101 (20): 4004-4008
  • Heterogeneous NO3- ion dynamics near the glass transition in the fragile ionic glass former Ca0.4K0.6(NO3)(1.4): A N-15 NMR study PHYSICAL REVIEW LETTERS Sen, S., Stebbins, J. F. 1997; 78 (18): 3495-3498
  • Cross-polarization from quadrupolar nuclei to silicon using low-radio-frequency amplitudes during magic-angle spinning JOURNAL OF PHYSICAL CHEMISTRY B DePaul, S. M., Ernst, M., Shore, J. S., Stebbins, J. F., Pines, A. 1997; 101 (16): 3240-3249
  • Multiple-quantum magic-angle spinning and dynamic-angle spinning NMR spectroscopy of quadrupolar nuclei SOLID STATE NUCLEAR MAGNETIC RESONANCE Wang, S. H., Xu, Z., BALTISBERGER, J. H., Bull, L. M., Stebbins, J. F., Pines, A. 1997; 8 (1): 1-16

    Abstract

    Several aspects of the Multiple-Quantum Magic-Angle Spinning (MQMAS) technique (L. Frydman and J.S. Harwood, J. Am. Chem. Soc., 117 (1995) 5367) are compared with Dynamic-Angle Spinning (DAS). Examples of MQMAS spectra are shown for I = 3/2 nuclei with CQ up to 3.6 MHz, and for 27Al (I = 5/2) with CQ up to 10 MHz. The MQMAS linewidth is largely independent of the magnitude of the homonuclear dipolar interaction, while the spinning sideband manifold is similar to that observed in DAS experiments. MQMAS is technically simple and routinely useful for studying nuclei with short spin-lattice relaxation times, but care must be taken in its use for quantitative studies as the excitation of the triple-quantum coherence is not uniform. In this regard, MQMAS is most useful for samples with small quadrupolar coupling constants. In the specific case of 17O, DAS would give spectra with excellent resolution in comparison to MQMAS. The different advantages of DAS and MQMAS make them useful complementary techniques in many cases. Two additional methods are also presented for extracting the chemical shift anisotropy (CSA) directly for quadrupolar nuclei using the multiple-quantum scheme.

    View details for Web of Science ID A1997WY62900001

    View details for PubMedID 9178419

  • Na-ion transport in borate and germanate glasses and liquids: A Na-23 and B-11 NMR spin-lattice-relaxation study PHYSICAL REVIEW B Sen, S., Stebbins, J. F. 1997; 55 (6): 3512-3519
  • Dynamics of Na in sodium aluminosilicate glasses and liquids PHYSICS AND CHEMISTRY OF MINERALS George, A. M., Stebbins, J. F. 1996; 23 (8): 526-534
  • Magnesium site exchange in forsterite: A direct measurement by high-temperature Mg-25 NMR spectroscopy AMERICAN MINERALOGIST Stebbins, J. F. 1996; 81 (11-12): 1315-1320
  • Silicon site distributions in an alkali silicate glass derived by two-dimensional Si-29 nuclear magnetic resonance JOURNAL OF NON-CRYSTALLINE SOLIDS Zhang, P., Dunlap, C., Florian, P., Grandinetti, P. J., Farnan, I., Stebbins, J. F. 1996; 204 (3): 294-300
  • Temperature effects on structure and dynamics in borate and borosilicate liquids: High-resolution and high-temperature NMR results JOURNAL OF THE AMERICAN CERAMIC SOCIETY Stebbins, J. F., Ellsworth, S. E. 1996; 79 (9): 2247-2256
  • Triple-quantum two-dimensional Al-27 magic-angle spinning nuclear magnetic resonance spectroscopic study of aluminosilicate and aluminate crystals and glasses JOURNAL OF THE AMERICAN CHEMICAL SOCIETY BALTISBERGER, J. H., Xu, Z., Stebbins, J. F., Wang, S. H., Pines, A. 1996; 118 (30): 7209-7214
  • Cation distribution in mixed alkali disilicate glasses JOURNAL OF THE AMERICAN CHEMICAL SOCIETY Florian, P., Vermillion, K. E., Grandinetti, P. J., Farnan, I., Stebbins, J. F. 1996; 118 (14): 3493-3497
  • Ionic conduction and mixed cation effect in silicate glasses and liquids: Na-23 and Li-7 NMR spin-lattice relaxation and a multiple-barrier model of percolation JOURNAL OF NON-CRYSTALLINE SOLIDS Sen, S., George, A. M., Stebbins, J. F. 1996; 197 (1): 53-64
  • CATION DYNAMICS AND DIFFUSION IN LITHIUM ORTHOSILICATE - 2-DIMENSIONAL LI-6 NMR SCIENCE Xu, Z., Stebbins, J. F. 1995; 270 (5240): 1332-1334
  • LI-6 NUCLEAR-MAGNETIC-RESONANCE CHEMICAL-SHIFTS, COORDINATION-NUMBER AND RELAXATION IN CRYSTALLINE AND GLASSY SILICATES SOLID STATE NUCLEAR MAGNETIC RESONANCE Xu, Z., Stebbins, J. F. 1995; 5 (1): 103-112

    Abstract

    Unlike 7Li magic-angle spinning nuclear magnetic resonance (MAS NMR) spectra, 6Li MAS NMR spectra of silicates are dominated by chemical shift effects, often have a very high resolution and hence can provide significant structural information. In this study we demonstrate a good correlation between 6Li isotropic chemical shifts and oxygen coordination number, and use this result to describe the range of coordination environments for Li in silicate glasses. We also show that the second-order quadrupolar shift for 7Li can often be derived from 7Li and 6Li MAS spectra acquired at a single magnetic field. For a series of natural lepidolite samples with significant but varying contents of Mn and Fe, spin-lattice relaxation data show a power-law behavior and a three-dimensional distribution of paramagnetic centers, but homonuclear dipolar couplings can be important. The 6Li spectrum for lithium orthosilicate (which has three-, four-, five- and six-coordinated Li) is consistent with that predicted by the X-ray structure.

    View details for Web of Science ID A1995TA30400010

    View details for PubMedID 8748648

  • HIGH-TEMPERATURE NA-23 MAS NMR DATA FOR ALBITE - COMPARISON TO CHEMICAL-SHIFT MODELS AMERICAN MINERALOGIST George, A. M., Stebbins, J. F. 1995; 80 (9-10): 878-884
  • SOLID-STATE O-17 MAGIC-ANGLE AND DYNAMIC-ANGLE SPINNING NMR-STUDY OF THE SIO2 POLYMORPH COESITE JOURNAL OF PHYSICAL CHEMISTRY Grandinetti, P. J., BALTISBERGER, J. H., Farnan, I., Stebbins, J. F., Werner, U., Pines, A. 1995; 99 (32): 12341-12348
  • SILICATE SPECIES EXCHANGE, VISCOSITY, AND CRYSTALLIZATION IN A LOW-SILICA MELT - IN-SITU HIGH-TEMPERATURE MAS NMR-SPECTROSCOPY AMERICAN MINERALOGIST Stebbins, J. F., Sen, S., Farnan, I. 1995; 80 (7-8): 861-864
  • STRUCTURAL ROLE OF ND3+ AND AL3+ CATIONS IN SIO2 GLASS - A SI-29 MAS-NMR SPIN-LATTICE RELAXATION, AL-27 NMR AND EPR STUDY JOURNAL OF NON-CRYSTALLINE SOLIDS Sen, S., Stebbins, J. F. 1995; 188 (1-2): 54-62
  • CATION-EXCHANGE RATES AND MOBILITY IN ALUMINUM-DOPED LITHIUM ORTHOSILICATE - HIGH-RESOLUTION LI-6 NMR RESULTS SOLID STATE IONICS Stebbins, J. F., Xu, Z., Vollath, D. 1995; 78 (1-2): L1-L8
  • MOBILITY AND RELAXATION DETERMINATIONS OF LITHIUM IN LITHIUM ALUMINATE CERAMICS USING SOLID-STATE NMR-SPECTROSCOPY CHEMISTRY OF MATERIALS Stewart, F. F., Stebbins, J. F., Peterson, E. S., Farnan, I., Dunham, S. O., Adams, E., Jennings, P. W. 1995; 7 (2): 363-367
  • High temperature nuclear magnetic resonance studies of oxide melts J. Non-Cryst. Solids Stebbins, J., Sen, S., George, A. 1995; 193: 298-305
  • Dynamics and structure of silicate and oxide melts: Nuclear magnetic resonance studies STRUCTURE, DYNAMICS AND PROPERTIES OF SILICATE MELTS Stebbins, J. F. 1995; 32: 191-246
  • Structure, Dynamics and Properties of Silicate Liquids edited by Stebbins, J. F., McMillan, P., Dingwell, D. 1995
  • Nuclear magnetic resonance of oxide glasses and melts Structure, Dynamics and Properties of Silicate Liquids Stebbins, J. Min. Soc. Am.. 1995: 191–246
  • Nuclear magnetic resonance spectroscopy of silicates and oxides in geochemistry and geophysics Handbook of Physical Constants, v. 2 Stebbins, J. American Geophysical Union. 1995: 303–332
  • OXYGEN DISPLACEMENT THROUGH THE FERROELECTRIC PHASE-TRANSITION OF BARIUM-TITANATE - HIGH-TEMPERATURE O-17 NMR JOURNAL OF THE AMERICAN CERAMIC SOCIETY Spearing, D. R., Stebbins, J. F. 1994; 77 (12): 3263-3266
  • DEOXYGENATION ANNEALING OF BI2SR2CACU2O8+DELTA SINGLE-CRYSTALS OBSERVED IN-SITU BY O-17 NMR PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS Farnan, I., Lombardo, L. W., Stebbins, J. F., Kapitulnik, A. 1994; 232 (1-2): 27-36
  • DIFFUSION AND THE DYNAMICS OF DISPLACIVE PHASE-TRANSITIONS IN CRYOLITE (NA3ALF6) AND CHIOLITE (NA5AL3F14) - MULTINUCLEAR NMR-STUDIES PHYSICS AND CHEMISTRY OF MINERALS Spearing, D. R., Stebbins, J. F., Farnan, I. 1994; 21 (6): 373-386
  • A NEW DEVICE FOR EXPANSIVITY MEASUREMENTS OF LIQUIDS AT HIGH-TEMPERATURE AND PRESSURE AND EXPANSIVITY DATA FOR LIQUID-TIN TO 1450-DEGREES-C REVIEW OF SCIENTIFIC INSTRUMENTS FISKE, P. S., Stebbins, J. F. 1994; 65 (10): 3258-3262
  • THE STRUCTURAL OF MG IN SILICATE LIQUIDS - A HIGH-TEMPERATURE MG-25, NA-23, AND SI-29 NMR-STUDY AMERICAN MINERALOGIST FISKE, P. S., Stebbins, J. F. 1994; 79 (9-10): 848-861
  • COORDINATION ENVIRONMENTS OF B-IMPURITIES IN CALCITE AND ARAGONITE POLYMORPHS - A B-11 MAS NMR-STUDY AMERICAN MINERALOGIST Sen, S., Stebbins, J. F., Hemming, N. G., GHOSH, B. 1994; 79 (9-10): 819-825
  • THE NATURE OF THE GLASS-TRANSITION IN A SILICA-RICH OXIDE MELT SCIENCE Farnan, I., Stebbins, J. F. 1994; 265 (5176): 1206-1209

    Abstract

    The atomic-scale dynamics of the glass-to-liquid transition are, in general, poorly understood in inorganic materials. Here, two-dimensional magic angle spinning nuclear magnetic resonance spectra collected just above the glass transition of K(2)Si(4)O(9) at temperatures as high as 583 degrees C are presented. Rates of exchange for silicon among silicate species, which involves Si-O bond breaking, have been measured and are shown to be closely related in time scale to those defined by viscosity. Thus, even at viscosities as high as 10(10) pascal seconds, local bond breaking (in contrast to the cooperative motion of large clusters) is of major importance in the control of macroscopic flow and diffusion.

    View details for Web of Science ID A1994PD42200028

    View details for PubMedID 17787585

  • PHASE-SEPARATION, CLUSTERING, AND FRACTAL CHARACTERISTICS IN GLASS - A MAGIC-ANGLE-SPINNING NMR SPIN-LATTICE RELAXATION STUDY PHYSICAL REVIEW B Sen, S., Stebbins, J. F. 1994; 50 (2): 822-830
  • CORRELATIONS BETWEEN O-17 NMR PARAMETERS AND LOCAL-STRUCTURE AROUND OXYGEN IN HIGH-PRESSURE SILICATES - IMPLICATIONS FOR THE STRUCTURE OF SILICATE MELTS AT HIGH-PRESSURE AMERICAN MINERALOGIST Xue, X. Y., Stebbins, J. F., Kanzaki, M. 1994; 79 (1-2): 31-42
  • NUCLEATION AND MEDIUM-RANGE ORDER IN SILICATE LIQUIDS - INFERENCES FROM NMR-SPECTROSCOPY Symposium on Crystallization and Related Phenomena in Amorphous Materials, at the 1993 Fall Meeting of the Materials-Research-Society Stebbins, J. F., Sen, S. MATERIALS RESEARCH SOC. 1994: 143–154
  • BONDING AND DYNAMICAL PHENOMENA IN MGO - A HIGH-TEMPERATURE O-17 AND MG-25 NMR-STUDY PHYSICS AND CHEMISTRY OF MINERALS FISKE, P. S., Stebbins, J. F., Farnan, I. 1994; 20 (8): 587-593
  • NA-23 NMR CHEMICAL-SHIFTS AND LOCAL NA COORDINATION ENVIRONMENTS IN SILICATE CRYSTALS, MELTS AND GLASSES PHYSICS AND CHEMISTRY OF MINERALS Xue, X. Y., Stebbins, J. F. 1993; 20 (5): 297-307
  • GEL SYNTHESIS OF AN ALBITE (NAALSI3O8) GLASS - AN NMR ANALYSIS GEOCHIMICA ET COSMOCHIMICA ACTA SCHMELZ, C. E., Stebbins, J. F. 1993; 57 (16): 3949-3960
  • ACCEPTANCE OF THE MINERALOGICAL-SOCIETY-OF-AMERICA AWARD FOR 1992 AMERICAN MINERALOGIST Stebbins, J. F. 1993; 78 (7-8): 856-857
  • COMPOSITIONAL AND TEMPERATURE EFFECTS ON 5-COORDINATED SILICON IN AMBIENT-PRESSURE SILICATE-GLASSES JOURNAL OF NON-CRYSTALLINE SOLIDS Stebbins, J. F., McMillan, P. 1993; 160 (1-2): 116-125
  • TETRAHEDRAL DISORDER IN FIBROLITIC SILLIMANITE - COMPARISON OF SI-29 NMR AND NEUTRON-DIFFRACTION DATA AMERICAN MINERALOGIST Stebbins, J. F., Burnham, C. W., Bish, D. L. 1993; 78 (3-4): 461-464
  • KINETICS AND MECHANISM OF LIGAND-EXCHANGE OF AU(III), ZN(II), AND CD(II) CHLORIDES IN AQUEOUS-SOLUTION - AN NMR-STUDY FROM 28-98-DEGREES-C GEOCHIMICA ET COSMOCHIMICA ACTA SHARPS, J. A., Brown, G. E., Stebbins, J. F. 1993; 57 (4): 721-731
  • A SI-29 MAS NMR-STUDY OF SUB-TG AMORPHIZATION OF STISHOVITE AT AMBIENT PRESSURE PHYSICS AND CHEMISTRY OF MINERALS Xue, X. Y., Stebbins, J. F., Kanzaki, M. 1993; 19 (7): 480-485
  • DYNAMICS OF THE ALPHA-BETA PHASE-TRANSITIONS IN QUARTZ AND CRISTOBALITE AS OBSERVED BY INSITU HIGH-TEMPERATURE SI-29 NMR AND O-17 NMR PHYSICS AND CHEMISTRY OF MINERALS Spearing, D. R., Farnan, I., Stebbins, J. F. 1992; 19 (5): 307-321
  • SOLIDS AND LIQUIDS IN THE NAF-ALF3-AL2O3 SYSTEM - A HIGH-TEMPERATURE NMR-STUDY JOURNAL OF THE AMERICAN CERAMIC SOCIETY Stebbins, J. F., Farnan, I., DANDO, N., Tzeng, S. Y. 1992; 75 (11): 3001-3006
  • QUANTIFICATION OF THE DISORDER IN NETWORK-MODIFIED SILICATE-GLASSES NATURE Farnan, I., Grandinetti, P. J., BALTISBERGER, J. H., Stebbins, J. F., Werner, U., Eastman, M. A., Pines, A. 1992; 358 (6381): 31-35

    Abstract

    Local order in silicate glasses has been observed by many experimental techniques to be similar to that in crystalline materials. Details of the intermediate-range order are more elusive, but essential for understanding the lack of long-range symmetry in glasses and the effect of composition on glass structure. Two-dimensional 17O dynamic-angle-spinning nuclear magnetic resonance experiments reveal intermediate-range order in the distribution of inter-tetrahedral (Si-O-Si) bond angles and a high degree of order in the disposition of oxygen atoms around the network-modifying cations.

    View details for Web of Science ID A1992JB34100043

    View details for PubMedID 1614527

  • NUCLEAR-MAGNETIC-RESONANCE SPECTROSCOPY OF GEOLOGICAL-MATERIALS MRS BULLETIN Stebbins, J. F. 1992; 17 (5): 45-52
  • EFFECTS OF HIGH-TEMPERATURE ON SILICATE LIQUID STRUCTURE - A MULTINUCLEAR NMR-STUDY SCIENCE Stebbins, J. F., Farnan, I. 1992; 255 (5044): 586-589

    Abstract

    The structure of a silicate liquid changes with temperature, and this substantially affects its thermodynamic and transport properties. Models used by geochemists, geophysicists, and glass scientists need to include such effects. In situ, high-temperature nuclear magnetic resonance (NMR) spectroscopy on (23)Na, (27)A1, and (29)Si was used to help determine the time-averaged structure of a series of alkali aluminosilicate liquids at temperatures to 1320 degrees C. Isotropic chemical shifts for (29)Si increase (to higher frequencies) with increasing temperature, probably in response to intermediate-range structural changes such as the expansion of bonds between nonbridging oxygens and alkali cations. In contrast, isotropic chemical shifts for (27)Al decrease with increasing temperature, indicating that more significant short-range structural changes take place for aluminum, such as an increase in mean coordination number. The spectrum of a sodium aluminosilicate glass clearly indicates that at least a few percent of six-coordinated aluminum was present in the liquid at high temperature.

    View details for Web of Science ID A1992HB53100039

    View details for PubMedID 17792382

  • X-RAY-POWDER DIFFRACTION AND NA-23, AL-27, AND SI-29 MAS-NMR INVESTIGATION OF NEPHELINE-KALSILITE CRYSTALLINE SOLUTIONS AMERICAN MINERALOGIST Hovis, G. L., Spearing, D. R., Stebbins, J. F., Roux, J., Clare, A. 1992; 77 (1-2): 19-29
  • The structure and dynamics of alkali silicate liquids: a view from NMR spectroscopy Chemical Geology Stebbins, J., Farnan, I., Xue, X. 1992: 371-385
  • Characterization of crystalline and amorphous silicates quenched from high pressure by 29Si MAS NMR spectroscopy High Pressure Research in Mineral Physics: Applications to Earth and Planetary Sciences Kanzaki, M., Stebbins, J., Xue, X. American Geophysical Union. 1992: 89–100
  • NUCLEAR-MAGNETIC-RESONANCE AT HIGH-TEMPERATURE CHEMICAL REVIEWS Stebbins, J. F. 1991; 91 (7): 1353-1373
  • NMR EVIDENCE FOR 5-COORDINATED SILICON IN A SILICATE GLASS AT ATMOSPHERIC-PRESSURE NATURE Stebbins, J. F. 1991; 351 (6328): 638-639
  • CHARACTERIZATION OF QUENCHED HIGH-PRESSURE PHASES IN CASIO3 SYSTEM BY XRD AND SI-29 NMR GEOPHYSICAL RESEARCH LETTERS Kanzaki, M., Stebbins, J. F., Xue, X. Y. 1991; 18 (3): 463-466
  • LOCAL-STRUCTURE AND CHEMICAL-SHIFTS FOR 6-COORDINATED SILICON IN HIGH-PRESSURE MANTLE PHASES SCIENCE Stebbins, J. F., Kanzaki, M. 1991; 251 (4991): 294-298

    Abstract

    Most of the earth's mantle is made up of high-pressure silicate minerals that contain octahedrally coordinated silicon (Si(VI)), but many thermodynamically important details of cation site ordering remain unknown. Silicon-29 nuclear magnetic resonance (NMR) spectroscopy is potentially very useful for determining short-range structure. A systematic study of silicon-29 chemical shifts for Si(VI) has revealed empirical correlations between shift and structure that are useful in understanding several new calcium silicates. The observed ordering state of a number of high-pressure magnesium silicates is consistent with the results of previous x-ray diffraction studies.

    View details for Web of Science ID A1991ET67800027

    View details for PubMedID 17733286

  • HIGH-RESOLUTION O-17 NMR OF SOLID SILICATES JOURNAL OF THE AMERICAN CHEMICAL SOCIETY Mueller, K. T., Wu, Y., Chmelka, B. F., Stebbins, J., Pines, A. 1991; 113 (1): 32-38
  • PRESSURE-INDUCED SILICON COORDINATION AND TETRAHEDRAL STRUCTURAL-CHANGES IN ALKALI OXIDE-SILICA MELTS UP TO 12 GPA - NMR, RAMAN, AND INFRARED-SPECTROSCOPY AMERICAN MINERALOGIST Xue, X. Y., Stebbins, J. F., Kanzaki, M., McMillan, P. F., Poe, B. 1991; 76 (1-2): 8-26
  • OBSERVATION OF SLOW ATOMIC MOTIONS CLOSE TO THE GLASS-TRANSITION USING 2-D SI-29 NMR JOURNAL OF NON-CRYSTALLINE SOLIDS Farnan, I., Stebbins, J. F. 1990; 124 (2-3): 207-215
  • HIGH-TEMPERATURE SI-29 NMR INVESTIGATION OF SOLID AND MOLTEN SILICATES JOURNAL OF THE AMERICAN CHEMICAL SOCIETY Farnan, I., Stebbins, J. F. 1990; 112 (1): 32-39
  • The structure of NaAlSi3O8 liquids at high pressure:new constraints from NMR spectroscopy Am. Mineral. Stebbins, J., Sykes, D. 1990; 75 (943-946): 943-946
  • ALUMINUM IN RUTILE (TIO2) - CHARACTERIZATION BY SINGLE-CRYSTAL AND MAGIC-ANGLE-SPINNING NUCLEAR MAGNETIC-RESONANCE JOURNAL OF THE AMERICAN CERAMIC SOCIETY Stebbins, J. F., Farnan, I., KLABUNDE, U. 1989; 72 (11): 2198-2200
  • SILICON COORDINATION AND SPECIATION CHANGES IN A SILICATE LIQUID AT HIGH-PRESSURES SCIENCE Xue, X. Y., Stebbins, J. F., Kanzaki, M., Tronnes, R. G. 1989; 245 (4921): 962-964

    Abstract

    Coordination and local geometry around Si cations in silicate liquids are of primary importance in controlling the chemical and physical properties of magmas. Pressure-induced changes from fourfold to sixfold coordination of Si in silicate glass samples quenched from liquids has been detected with (29)Si magic-angle spinning nuclear magnetic resonance spectrometry. Samples of Na(2)Si(2)O(5) glass quenched from 8 gigapascals and 1500 degrees C contained about 1.5 percent octahedral Si, which was demonstrably part of a homogeneous, amorphous phase. The dominant tetrahedral Si speciation in these glasses became disproportionated to a more random distribution of bridging and nonbridging oxygens with increasing pressure.

    View details for Web of Science ID A1989AM93300023

    View details for PubMedID 17780537

  • NUCLEAR MAGNETIC-RESONANCE SPECTROSCOPY IN THE EARTH SCIENCES - STRUCTURE AND DYNAMICS SCIENCE Stebbins, J. F., Farnan, I. 1989; 245 (4915): 257-263

    Abstract

    Detailed knowledge of the structure and dynamics of the materials that make up the earth is necessary for fundamental understanding of most geological processes. Nuclear magnetic resonance spectroscopy is beginning to play an important role in investigations of inorganic solid materials, as well as of liquids and organic compounds; it has already contributed substantially to our knowledge of minerals and rocks, compositionally simplified analogs of magmas, and the surfaces of silicate crystals. The technique is particularly useful for determining local structure and ordering state in crystals, glasses, and liquids, and is sensitive to atomic motion at the time scales of diffusion and viscosity in silicates. New techniques offer promise for increased resolution for quadrupolar nuclei and for extension of experiments to high temperature and pressure.

    View details for Web of Science ID A1989AF96200020

    View details for PubMedID 17834676

  • LACK OF LOCAL STRUCTURAL ORIENTATION IN OXIDE GLASSES QUENCHED DURING FLOW - NMR RESULTS JOURNAL OF NON-CRYSTALLINE SOLIDS Stebbins, J. F., Spearing, D. R., Farnan, I. 1989; 110 (1): 1-12
  • THE SI-29 NMR SHIELDING TENSOR IN LOW QUARTZ AMERICAN MINERALOGIST Spearing, D. R., Stebbins, J. F. 1989; 74 (7-8): 956-959
  • O-17 NMR IN SOLIDS BY DYNAMIC-ANGLE SPINNING AND DOUBLE ROTATION NATURE Chmelka, B. F., Mueller, K. T., Pines, A., Stebbins, J., Wu, Y., Zwanziger, J. W. 1989; 339 (6219): 42-43
  • MAGIC ANGLE SPINNING NMR OBSERVATION OF SODIUM SITE EXCHANGE IN NEPHELINE AT 500-DEGREES-C PHYSICS AND CHEMISTRY OF MINERALS Stebbins, J. F., Farnan, I., Williams, E. H., Roux, J. 1989; 16 (8): 763-766
  • Five- and six- coordinated Si in K2Si4O9 glass quenched from 1.9 GPa and 1200 C American Mineralogist Stebbins, J., McMillan, P. 1989; 74: 965-968
  • DISORDERING AND THE PROGRESS OF HYDRATION AT THE SURFACE OF DIOPSIDE - A CROSS-POLARIZATION MAS-NMR STUDY GEOCHIMICA ET COSMOCHIMICA ACTA Peck, J. A., Farnan, I., Stebbins, J. F. 1988; 52 (12): 3017-3021
  • EFFECTS OF TEMPERATURE AND COMPOSITION ON SILICATE GLASS STRUCTURE AND DYNAMICS - SI-29 NMR RESULTS JOURNAL OF NON-CRYSTALLINE SOLIDS Stebbins, J. F. 1988; 106 (1-3): 359-369
  • EFFECTS OF TEMPERATURE ON THE STRUCTURES OF SILICATE LIQUIDS - SI-29 NMR RESULTS GEOCHIMICA ET COSMOCHIMICA ACTA Brandriss, M. E., Stebbins, J. F. 1988; 52 (11): 2659-2669
  • DIFFUSIVE MOTION IN ALKALI SILICATE MELTS - AN NMR-STUDY AT HIGH-TEMPERATURE GEOCHIMICA ET COSMOCHIMICA ACTA Liu, S. B., Stebbins, J. F., Schneider, E., Pines, A. 1988; 52 (2): 527-538
  • A SI-29 NUCLEAR MAGNETIC-RESONANCE STUDY OF SILICON-ALUMINUM ORDERING IN LEUCITE AND ANALCITE PHYSICS AND CHEMISTRY OF MINERALS Murdoch, J. B., Stebbins, J. F., Carmichael, I. S., Pines, A. 1988; 15 (4): 370-382
  • NMR-SPECTROSCOPY AND DYNAMIC PROCESSES IN MINERALOGY AND GEOCHEMISTRY REVIEWS IN MINERALOGY Stebbins, J. F. 1988; 18: 405-429
  • IDENTIFICATION OF MULTIPLE STRUCTURAL SPECIES IN SILICATE-GLASSES BY SI-29 NMR NATURE Stebbins, J. F. 1987; 330 (6147): 465-467

    Abstract

    Knowledge of the structure of silicate glasses is one key to understanding their chemical and physical properties, as well as those of the high-temperature liquids from which they form. Because first-neighbour ordering into SiO4 tetrahedra is well known, much of the recent discussion about glass structure has concerned intermediate-range order. One of the most fundamental questions that can be posed is the distribution of silicate tetrahedra with n bridging oxygens (shared between two tetrahedra), labelled as 'Qn' (0 less than or equal to n less than or equal to 4). This distribution is probably important in determining the properties of melts and glasses, but considerable controversy exists concerning the identification and quantification of such species. Here I present new evidence from 29Si NMR (nuclear magnetic resonance) spectroscopy that clearly resolves one significant part of this dispute: at least in sodium silicate glasses, a variety of species is present that is greater than that required by composition alone.

    View details for Web of Science ID A1987L083900057

    View details for PubMedID 2825026

  • SPECIATION AND LOCAL-STRUCTURE IN ALKALI AND ALKALINE-EARTH SILICATE-GLASSES - CONSTRAINTS FROM SI-29 NMR-SPECTROSCOPY JOURNAL OF NON-CRYSTALLINE SOLIDS Schneider, E., Stebbins, J. F., Pines, A. 1987; 89 (3): 371-383
  • RELAXATION MECHANISMS AND EFFECTS OF MOTION IN ALBITE (NAALSI3O8) LIQUID AND GLASS - A HIGH-TEMPERATURE NMR-STUDY PHYSICS AND CHEMISTRY OF MINERALS Liu, S. B., Pines, A., BRANDRISS, M., Stebbins, J. F. 1987; 15 (2): 155-162
  • PHASE-TRANSITIONS IN LEUCITE (KALSI2O6), ORTHORHOMBIC KALSIO4, AND THEIR IRON ANALOGS (KFESI2O6, KFESIO4) AMERICAN MINERALOGIST Lange, R. A., Carmichael, I. S., Stebbins, J. F. 1986; 71 (7-8): 937-945
  • DENSITY OF MOLTEN SODIUM ALUMINOSILICATES JOURNAL OF THE AMERICAN CERAMIC SOCIETY Stein, D. J., Stebbins, J. F., Carmichael, I. S. 1986; 69 (5): 396-399
  • NEW PROBE FOR HIGH-TEMPERATURE NMR-SPECTROSCOPY WITH PPM RESOLUTION REVIEW OF SCIENTIFIC INSTRUMENTS Stebbins, J. F., Schneider, E., Murdoch, J. B., Pines, A., Carmichael, I. S. 1986; 57 (1): 39-42
  • DEFECTS AND SHORT-RANGE ORDER IN NEPHELINE GROUP MINERALS - A SI-29 NUCLEAR-MAGNETIC-RESONANCE STUDY PHYSICS AND CHEMISTRY OF MINERALS Stebbins, J. F., Murdoch, J. B., Carmichael, I. S., Pines, A. 1986; 13 (6): 371-381
  • A HIGH-TEMPERATURE HIGH-RESOLUTION NMR-STUDY OF NA-23, AL-27 AND SI-29 IN MOLTEN SILICATES NATURE Stebbins, J. F., Murdoch, J. B., Schneider, E., Carmichael, I. S., Pines, A. 1985; 314 (6008): 250-252
  • HIGH-RESOLUTION SI-29 NMR-STUDY OF SILICATE AND ALUMINOSILICATE GLASSES - THE EFFECT OF NETWORK-MODIFYING CATIONS AMERICAN MINERALOGIST Murdoch, J. B., Stebbins, J. F., Carmichael, I. S. 1985; 70 (3-4): 332-343
  • HEAT-CAPACITIES AND ENTROPIES OF SILICATE LIQUIDS AND GLASSES CONTRIBUTIONS TO MINERALOGY AND PETROLOGY Stebbins, J. F., Carmichael, I. S., MORET, L. K. 1984; 86 (2): 131-148
  • THE HEAT OF FUSION OF FAYALITE AMERICAN MINERALOGIST Stebbins, J. F., Carmichael, I. S. 1984; 69 (3-4): 292-297
  • THE HIGH-TEMPERATURE LIQUID AND GLASS HEAT CONTENTS AND THE HEATS OF FUSION OF DIOPSIDE, ALBITE, SANIDINE AND NEPHELINE AMERICAN MINERALOGIST Stebbins, J. F., Carmichael, I. S., WEILL, D. E. 1983; 68 (7-8): 717-730
  • SOME THERMODYNAMIC AND EXPERIMENTAL CONSTRAINTS ON THE MELTING OF ALBITE AT ATMOSPHERIC AND HIGH-PRESSURE JOURNAL OF GEOLOGY NAVROTSKY, A., Capobianco, C., Stebbins, J. 1982; 90 (6): 679-698
  • THE PARTIAL MOLAR VOLUME OF FE2O3 IN MULTICOMPONENT SILICATE LIQUIDS AND THE PRESSURE-DEPENDENCE OF OXYGEN FUGACITY IN MAGMAS MINERALOGICAL MAGAZINE Mo, X., Carmichael, I. S., Rivers, M., Stebbins, J. 1982; 45: 237-245
  • HIGH-TEMPERATURE HEAT CONTENTS AND HEAT-CAPACITIES OF LIQUIDS AND GLASSES IN THE SYSTEM NAALSI3O8-CAAL2SI2O8 CONTRIBUTIONS TO MINERALOGY AND PETROLOGY Stebbins, J. F., WEILL, D. F., Carmichael, I. S., MORET, L. K. 1982; 80 (3): 276-284
  • THE ENTHALPY OF FUSION OF ANORTHITE CONTRIBUTIONS TO MINERALOGY AND PETROLOGY WEILL, D. F., Stebbins, J. F., Hon, R., Carmichael, I. S. 1980; 74 (1): 95-102
  • The nature and petrogenesis of intra-oceanic plate alkaline eruptive and plutonic rocks: King's Trough, Northeast Atlantic J. Volcan. and Geotherm. Stebbins, J., Thompson, G. 1978; 4: 333-361