Ligand K-Edge X-ray Absorption Spectroscopy: A Direct Probe of Ligand−Metal Covalency
- 23 September 2000
- journal article
- Published by American Chemical Society (ACS) in Accounts of Chemical Research
- Vol. 33 (12), 859-868
- https://doi.org/10.1021/ar990125c
Abstract
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 [MCl4]n-, metal tetrathiolates [M(SR)4]n-, and dimeric iron−sulfur (Fe−S) clusters [Fe2S2(SR)4]2-. It is then applied to blue Cu proteins, the CuA 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.Keywords
This publication has 15 references indexed in Scilit:
- Electronic structure contributions to electron transfer in blue Cu and Cu(A).JBIC Journal of Biological Inorganic Chemistry, 2000
- Ligand K-Edge and Metal L-Edge X-ray Absorption Spectroscopy and Density Functional Calculations of Oxomolybdenum Complexes with Thiolate and Related Ligands: Implications for Sulfite OxidaseJournal of the American Chemical Society, 1999
- Investigation of Iron−Sulfur Covalency in Rubredoxins and a Model System Using Sulfur K-Edge X-ray Absorption SpectroscopyJournal of the American Chemical Society, 1998
- Ligand K-edge X-ray absorption spectroscopic studies: metal-ligand covalency in transition metal tetrathiolatesInorganica Chimica Acta, 1997
- Ligand K-edge x-ray absorption spectroscopic studies: metal-ligand covalency in a series of transition metal tetrachloridesJournal of the American Chemical Society, 1995
- Ligand K-Edge X-ray Absorption Spectroscopy as a Probe of Ligand-Metal Bonding: Charge Donation and Covalency in Copper-Chloride SystemsInorganic Chemistry, 1994
- Active-site electronic structure contributions to electron-transfer pathways in rubredoxin and plastocyanin: direct versus superexchangeJournal of the American Chemical Society, 1993
- X-ray absorption spectroscopic studies of the blue copper site: metal and ligand K-edge studies to probe the origin of the EPR hyperfine splitting in plastocyaninJournal of the American Chemical Society, 1993
- X-ray absorption edge spectroscopy of ligands bound to open-shell metal ions: chlorine K-edge studies of covalency in tetrachlorocuprate(2-)Journal of the American Chemical Society, 1990
- Satellite structure in photoelectron and Auger spectra of copper dihalidesPhysical Review B, 1981