Direct Detection of Oxygen Ligation to the Mn₄Ca Cluster of Photosystem II by X‐ray Emission Spectroscopy

Abstract

Seeing O: Mn Kβ2,5 and Kβ′′ X‐ray emission spectra arise from transitions from the ligand 2s and 2p shells of the metal complexes to the metal 1s levels. In biological systems, it is difficult to specifically probe the O and N ligands. This spectroscopic technique is used to study the O ligands of the Mn4Ca cluster that catalyzes photosynthetic water splitting and allows direct detection for the first time of the bridging oxo groups of Mn.

Chemical state of phosphorus in amorphous Ni–Fe–P electroplates

“…In the recent works it was demonstrated a high potential of vtc-XES for the determination of ligand environment of 3d metals in coordination and metalorganic compounds [15][16][17], enzymes [18,19], catalysts with amorphous structure [20] etc. In most cases distinguishing of O, N, C, P ligands in the first coordination shell of 3d metals was impossible by other methods.…”

Benchmark results and theoretical treatments for valence-to-core x-ray emission spectroscopy in transition metal compounds

“…[47][48][49][50][51][52][53] While the semi-core and deeper core transitions involved in XES are often reasonably well described by perturbed atomic multiplet approaches due to the extreme localization of the atomic-like initial and final states, the situation is markedly less clear for those transitions involving valence electron density of the host species and ligands.…”

X-ray Absorption and Emission Study of Dioxygen Activation by a Small-Molecule Manganese Complex

“…Identifying changes in ligand or substrate structure, e.g., dioxygen activation, are frequently of equal or greater interest. 15,23 To this end we have therefore investigated the series of Mn complexes described above ( 1–3 ) using a combined absorption and emission X-ray spectroscopic approach.…”

“…23,26–30 The inherent element-specificity of transitions involving a 1s core electron makes it an ideal choice for the study of metalloenzymes, where the atom(s) of interest in the sample is often a mere fraction of a percent by mass. Additionally, the various regions of the XAS spectrum can yield information regarding coordination number and geometry, oxidation state, and metal–ligand distances.…”