Theoretical study of dibenzyl disulfide adsorption on Cu7 cluster as a first approximation to sulfur-induced copper corrosion process.

The adsorption of dibenzyl disulfide (DBDS) on a pentagonal bipyramid Cu7 cluster was investigated by using density functional calculations, from energetic and electronic viewpoints. The resulting complexes are mainly driven by Cu···S interaction, and an extra stabilization can be conferred by a secondary π···Cu weak interaction. They were classified as physi- or chemisorption according to their binding energy, and by applying a distortion/interaction decomposition model. Disulfide bond dissociation was observed in the most stable complexes, which includes higher distortion energy. From an electronic viewpoint, an electronic flow from copper to DBDS was observed. [ABSTRACT FROM AUTHOR]