2000/09/23 by Thorsten Glaser, Britt Hedman, Keith O. Hodgson +1 · 4 citations
Energy · #Metalloenzymes and iron-sulfur proteins #Electrocatalysts for Energy Conversion #CO2 Reduction Techniques and Catalysts
paper · doi:10.1021/ar990125c
openalex publication_date 2000/09/23 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/01
Ligand K-edge X-ray absorption spectroscopy (XAS) is a new experimental probe of the covalency of a metal-ligand bond. The intensity of the ligand pre-edge feature is proportional to the mixing of ligand orbitals into the metal d orbitals. The methodology to determine covalencies in one-electron (hole) and many-electron systems is described and demonstrated for a series of metal tetrachlorides [MCl(4)](n)(-), metal tetrathiolates [M(SR)(4)](n)(-), and dimeric iron-sulfur (Fe-S) clusters [Fe(2)S(2)(SR)(4)](2-). It is then applied to blue Cu proteins, the Cu(A) site, hydrogen bonding in Fe-S clusters, and the delocalization behavior in [2Fe-2S] vs [4Fe-4S] clusters. The covalencies determined in these studies provide important electronic structure insight into function.