Density functional description of the bonding in the m3-chalcogenido hexanuclear octahedral clusters [Co6(m3-X)8(Pet3)6 ] (X=S, Se, Te)

Density functional theory (DFT) in the local density approximation has been applied to describe the bonding in the μ3-chalcogenido hexanuclear cobalt clusters of formula [Co6(μ3-X)8(PR3)6] (X = S, Se, Te). The geometries of the clusters have been optimised and the bonding interactions in the sulfide derivative have been analysed using a fragment decomposition scheme. Direct metal-metal interactions are negligible. The electrochemical behaviour reported for the sulfide cluster has been rationalised.