2025/04/04 by Liya Bi, Zhe Wang, Bi, Liya +13
Engineering · Materials Science · #FOS: Physical sciences #Magnetism in coordination complexes #Mesoscale and Nanoscale Physics (cond-mat.mes-hall) #Molecular Junctions and Nanostructures #Surface Chemistry and Catalysis
paper · pdf · doi:10.48550/arxiv.2504.03945
openalex publication_date 2025/04/04 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Isocyanide-metal binding is governed by sigma-donation and pi-back-bonding, which affects the energy of the isocyanide stretching mode-a characteristic probe for ligand-metal interactions. While extensive correlations exist between structure and spectroscopy in molecular isocyanide-metal systems, isocyanide interactions with metallic crystalline surfaces, where ligands often bind in various geometries, remain poorly understood. Conventional vibrational spectroscopies, such as infrared and Raman, lack the molecular-scale resolution needed to distinguish these inhomogeneous configurations. In contrast, inelastic electron tunneling spectroscopy with scanning tunneling microscopy (STM-IETS) enables direct visualization of ligand adsorption geometries and their vibrational signatures. Using STM-IETS, here we investigate a matal-adsorbed m-terphenyl isocyanie ligand and find that adsorption geometry on Cu(100) induces a significant shift in isocyanide stretching frequency, even greater than replacing Cu(100) with Ag(111). Density functional theory confirms this shift arises from atomic-scale variations in isocyanide-metal binding. This study elucidates how atomic-scale binding influences the vibrational signatures of isocyanide ligands-an often-overlooked factor in understanding isocyanide-metal interactions.