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-Cu₃]ⁿ; n = 0, −1, −2, −3; L = Ph₂PNTol^–, 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-D₃ symmetry. Paramagnetic ³¹P 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-Cu₃]^3– to 1-Cu₃ 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.