Medium and Interfacial Effects in the Multistep Reduction of Binuclear Complexes with Robson-Type Ligand

Abstract

We present a combined experimental and computational approach to the modeling and prediction of reactivity in multistep processes of heterogeneous electron transfer. The approach is illustrated by the study of a Robson-type binuclear complex (-Cu(II)-Cu(II)-) undergoing four-electron reduction in aqueous media and water-acetonitrile mixtures. The observed effects of solvent, pH, buffer capacity, and supporting electrolyte are discussed in the framework of a general reaction scheme involving two main routes; one of them includes protonation of intermediate species. The main three problems are addressed on the basis of modern charge transfer theory: (1) the effect of the nature of reactant and intermediate species (protonated/deprotonated, bare or associated with supporting anion/solvent molecule) on the standard redox potential, the electronic transmission coefficient, and the intramolecular reorganization; (2) possible effect of protonation on the shape of the reaction free energy surfaces which are built using the Anderson Hamiltonian; (3) electron transfer across an adsorbed chloride anion. Quantum chemical calculations were performed at the density functional theory level.

Modeling of electron transfer across electrochemical interfaces: State‐of‐the art and challenges for quantum and computational chemistry

“…A quantum‐chemical approach to calculate U was developed in Refs. . The authors modeled a two‐step electron transfer at the electrochemical reduction of [Zn(H 2 O) 6 ] 2+ , [In(H 2 O) 6 ] 3+ , and [In(H 2 O) 5 OH] 2+ complex ions; the multi‐step reduction of binuclear complexes with Robson‐type ligand was investigated in Ref.…”

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Influence of Solvents on Protolytic and Aggregation Properties of Aminomethylated Calix[4]resorcine

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Electron transfer across a conducting nanowire (nanotube)/electrolyte solution interface

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