Probing electronic structures of metal complexes from the ligand side using soft x-ray absorption spectroscopy
Fumitoshi Kumaki1,2, Masanari Nagasaka3,4
1Photon Factory, Institute of Materials Structure Science, High Energy Accelerator Research Organization, 1-1 Oho, Tsukuba, Ibaraki 305-0801, Japan.
None:
Metal-ligand delocalization in metal complexes participating in various chemical processes was probed from the ligand side using nitrogen K-edge x-ray absorption spectroscopy (XAS). The electronic structures, spin multiplicities, and hydration structures of metal complexes in solutions with different metal ion centers, such as iron and cobalt protoporphyrin IX complexes, were investigated by N K-edge XAS. The influence of a phytol chain in chlorophyllain the solid phase was studied by the XAS measurements with a radiation-induced effect which may cleave the phytol chain. Time-resolved N K-edge XAS measurements at the 100 ps timescale were used to examine the photorelaxation process of iron phenanthroline complexes in aqueous solution. Future directions of studies of various chemical and biological processes that involve metal complexes using N K-edge XAS measurements of ligands are discussed.
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