Christina Deschene

All Publications

• Mixed-valence halide perovskites☆ COORDINATION CHEMISTRY REVIEWS Deschene, C. R., Zwanziger, C., Matheu, R., Karunadasa, H. I. 2025; 539

  View details for DOI 10.1016/j.ccr.2025.216719

  View details for Web of Science ID 001494564700001

• Suppressing Phase Transitions and High-Pressure Amorphization through Tethered Organic Cations in Organochalcogenide-Halide Perovskites. Journal of the American Chemical Society Li, J., Hofmann, J., Stolz, R. M., Wen, J., Deschene, C. R., Bartels, H., Liu, Z., Salleo, A., Lin, Y., Chapman, K. W., Karunadasa, H. I. 2025

  Abstract

  Polymorphism, where the same composition adopts different structures, is abundant in perovskites, with numerous phase transitions occurring as a function of temperature and pressure. The APbX3 perovskites (A = monovalent cation; X = Cl-, Br-, I-) show such phase transitions near ambient conditions, significantly impacting their optoelectronic device performance and stability. Herein, we show that the recently reported organochalcogenide-halide perovskites (RCh)PbX2 (RCh = +NH3(CH2)2S-, +NH3(CH2)2Se-; X = Cl-, Br-) featuring an organic A-site cation that is covalently linked to the inorganic framework, show no phase transitions with temperature from 4 to 423 K and with pressure from 0 to 40 GPa. Furthermore, the RCh-perovskites remain crystalline even at 40 GPa, in striking contrast to AMX3 (M = Pb, Sn) perovskites that rapidly become amorphous at pressures above ca. 5 GPa. By alloying RCh or the similar-sized ethylammonium as impurities into a (CH3NH3)PbBr3 host, we find that the enhanced phase integrity of the RCh-perovskites may be attributed mostly to the covalent attachment of the A-site cation, which impedes octahedral tilting, a primary avenue for phase transitions. We also track the rotational isomerization of the RCh ligands with pressure, finding that the trans-to-gauche isomerization enables a shrinking A-site cavity volume, without drastic changes to the inorganic framework. Unlike the dynamic disorder seen in hybrid perovskite A-site cations, this static rotational isomerism appears to be unaffected by temperature from 93 to 373 K. The exceptional structural integrity of the RCh-perovskites motivates the design of similar strategies to impede phase transitions in technologically important perovskite compositions.

  View details for DOI 10.1021/jacs.5c03696

  View details for PubMedID 40377980

• Stabilizing Au2+ in a mixed-valence 3D halide perovskite NATURE CHEMISTRY Lindquist, K. P., Eghdami, A., Deschene, C. R., Heyer, A. J., Wen, J., Smith, A. G., Solomon, E. I., Lee, Y. S., Neaton, J. B., Ryan, D. H., Karunadasa, H. I. 2023

  View details for DOI 10.1038/s41557-023-01305

  View details for Web of Science ID 001064800000001