Synthesis and characterization of low-dimensional N-heterocyclic carbene lattices

• 成果类型: Article
• 署名作者: Qie, Boyu; Wang, Ziyi; Jiang, Jingwei; Zhang, Zisheng; Jacobse, Peter H.; Lu, Jiaming; Li, Xinheng; Liu, Fujia; Alexandrova, Anastassia N.; Louie, Steven G.; Crommie, Michael F.; Fischer, Felix R.
• 署名单位: University of California System; University of California Berkeley; University of California System; University of California Berkeley; United States Department of Energy (DOE); Lawrence Berkeley National Laboratory; University of California System; University of California Berkeley; United States Department of Energy (DOE); Lawrence Berkeley National Laboratory; University of California System; University of California Los Angeles; University of California System; University of California Los Angeles; University of California System; University of California Los Angeles; University of California System; University of California Berkeley
• 刊物名称: SCIENCE
• ISSN/ISSBN: 0036-10993
• DOI: 10.1126/science.adm9814
• 发表日期: 2024-05-24
• 页码: 895-901
• 关键词: self-assembled monolayers; films

摘要

The covalent interaction of N-heterocyclic carbenes (NHCs) with transition metal atoms gives rise to distinctive frontier molecular orbitals (FMOs). These emergent electronic states have spurred the widespread adoption of NHC ligands in chemical catalysis and functional materials. Although formation of carbene-metal complexes in self-assembled monolayers on surfaces has been explored, design and electronic structure characterization of extended low-dimensional NHC-metal lattices remains elusive. Here we demonstrate a modular approach to engineering one-dimensional (1D) metal-organic chains and two-dimensional (2D) Kagome lattices using the FMOs of NHC-Au-NHC junctions to create low-dimensional molecular networks exhibiting intrinsic metallicity. Scanning tunneling spectroscopy and first-principles density functional theory reveal the contribution of C-Au-C pi-bonding states to dispersive bands that imbue 1D- and 2D-NHC lattices with exceptionally small work functions.