Exploring Charge Redistribution at the Cu/Co6Se8 Interface

This study investigates the electronic interactions and charge redistribution at the dopant-support interface using a Cu/Co6Se8 cluster construct. Specifically, the redox cluster series [Cu3Co6Se8L6](n) ([1-Cu-3](n); n = 0, -1, -2, -3; L = Ph(2)PNTol(-), Ph = phenyl, Tol = p-tolyl) spanning four distinct oxidation states is synthesized and characterized using a multitude of techniques, including multinuclear NMR, UV-vis, XANES, and X-ray crystallography. Structural investigations indicate that the clusters are isostructural and chiral, adopting a pseudo-D-3 symmetry. Paramagnetic P-31 NMR spectroscopy and solution-phase magnetic measurements together with DFT calculations are employed to interrogate the electronic structure and spin-state changes across the [1-Cu-3](3-) to 1-Cu-3 redox series, revealing that the copper edge sites retain a +1 oxidation state while the Co/Se core becomes increasingly oxidized, yielding a highly zwitterionic cluster.