Spin-state effects on the outer core-level multiplet structures for high-spin Mn molecular clusters

Oxo-bridged manganese polynuclear complexes have applications in a variety of technologies, such as single-molecule nanomagnets, catalysis, and photosynthetic redox chemistry. X-ray photoemission spectroscopy was used to study the Mn 3p, 3s, and valence hand electronic behavior as a function of Mn cluster structural properties, where the cluster size and, nuclearity are systematically varied. Results show a chemical shift of the Mn 3P(3/2,1/2) spin-orbit pair related to the cluster size and nuclearity. In addition, the Mn 3s S-7 and S-5. final state multiplet components shift since they involve the binding energy of a ligand valence electron. In addition, the branching ratio of the S-7:S-5 states is related to the 3s-3d electron correlation. Specifically, in the S-7 state, the remaining 3s electron is well correlated with 3d electrons of parallel spin, while in the S-5 state, the two spins are antiparallel. Changes in this electron correlation are clearly observed in the S-7:S-5 branching ratio as a function of cluster size and ligand electronegativity. (C) 2003 American Institute. of Physics.