Theoretical investigations of the influence of phosphine ligands on the structure of the compounds [Cu12S6(PR3)8]

MP2 and DFT methods are applied to calculate structural data and energetics of the compounds [Cu12S6(PR3)(8)]. So far, the formation of two different cluster types - depending on the ligand employed - could be proved by X-ray crystallography. The calculations have been performed to investigate the influence of the organic ligand groups R on the structure of the cluster core. The computed structural constants show good agreement with experiment. But neither structural data nor the calculated relative energies of the [Cu12S6(PR3)(8)] clusters permit a direct rationalization for the experimental behaviour. (C) 1998 Published by Elsevier Science B.V.