Xiang Zhu

All Publications

• Artificial kagome lattices of Shockley surface states patterned by halogen hydrogen-bonded organic frameworks. Nature communications Yin, R., Zhu, X., Fu, Q., Hu, T., Wan, L., Wu, Y., Liang, Y., Wang, Z., Qiu, Z. L., Tan, Y. Z., Ma, C., Tan, S., Hu, W., Li, B., Wang, Z. F., Yang, J., Wang, B. 2024; 15 (1): 2969

  Abstract

  Artificial electronic kagome lattices may emerge from electronic potential landscapes using customized structures with exotic supersymmetries, benefiting from the confinement of Shockley surface-state electrons on coinage metals, which offers a flexible approach to realizing intriguing quantum phases of matter that are highly desired but scarce in available kagome materials. Here, we devise a general strategy to construct varieties of electronic kagome lattices by utilizing the on-surface synthesis of halogen hydrogen-bonded organic frameworks (XHOFs). As a proof of concept, we demonstrate three XHOFs on Ag(111) and Au(111) surfaces, which correspondingly deliver regular, breathing, and chiral breathing diatomic-kagome lattices with patterned potential landscapes, showing evident topological edge states at the interfaces. The combination of scanning tunnelling microscopy and noncontact atomic force microscopy, complemented by density functional theory and tight-binding calculations, directly substantiates our method as a reliable and effective way to achieve electronic kagome lattices for engineering quantum states.

  View details for DOI 10.1038/s41467-024-47367-5

  View details for PubMedID 38582766

  View details for PubMedCentralID 9204828

• Revealing Intramolecular Isotope Effects with Chemical-Bond Precision. Journal of the American Chemical Society Zhu, X., Xu, J., Zhang, Y., Li, B., Tian, Y., Wu, Y., Liu, Z., Ma, C., Tan, S., Wang, B. 2023

  Abstract

  Isotope substitution of a molecule not only changes its vibrational frequencies but also changes its vibrational distributions in real-space. Quantitatively measuring the isotope effects inside a polyatomic molecule requires both energy and spatial resolutions at the single-bond level, which has been a long-lasting challenge in macroscopic techniques. By achieving ångström resolution in tip-enhanced Raman spectroscopy (TERS), we record the corresponding local vibrational modes of pentacene and its fully deuterated form, enabling us to identify and measure the isotope effect of each vibrational mode. The measured frequency ratio νH/νD varies from 1.02 to 1.33 in different vibrational modes, indicating different isotopic contributions of H/D atoms, which can be distinguished from TERS maps in real-space and well described by the potential energy distribution simulations. Our study demonstrates that TERS can serve as a non-destructive and highly sensitive methodology for isotope detection and recognition with chemical-bond precision.

  View details for DOI 10.1021/jacs.3c02728

  View details for PubMedID 37338304

• Determining structural and chemical heterogeneities of surface species at the single-bond limit SCIENCE Xu, J., Zhu, X., Tan, S., Zhang, Y., Li, B., Tian, Y., Shan, H., Cui, X., Zhao, A., Dong, Z., Yang, J., Luo, Y., Wang, B., Hou, J. G. 2021; 371 (6531): 818-+

  Abstract

  The structure determination of surface species has long been a challenge because of their rich chemical heterogeneities. Modern tip-based microscopic techniques can resolve heterogeneities from their distinct electronic, geometric, and vibrational properties at the single-molecule level but with limited interpretation from each. Here, we combined scanning tunneling microscopy (STM), noncontact atomic force microscopy (AFM), and tip-enhanced Raman scattering (TERS) to characterize an assumed inactive system, pentacene on the Ag(110) surface. This enabled us to unambiguously correlate the structural and chemical heterogeneities of three pentacene-derivative species through specific carbon-hydrogen bond breaking. The joint STM-AFM-TERS strategy provides a comprehensive solution for determining chemical structures that are widely present in surface catalysis, on-surface synthesis, and two-dimensional materials.

  View details for DOI 10.1126/science.abd1827

  View details for Web of Science ID 000619664700051

  View details for PubMedID 33602852