SYNTHESIS, CHARACTERIZATION AND ELECTRONIC-STRUCTURE OF THE NOVEL STELLATED OCTAHEDRAL CLUSTER [CO-6(MU(3)-S)(7)(MU(3)-H)-(PET(3))(6)](+) - CRYSTAL AND MOLECULAR-STRUCTURE OF [CO-6(MU(3)-S)(7)-(MU(3)-H)(PET(3))(6)](0.7)[CO-6(MU(3)-S)(8)(PET(3))(6)](0.3)[BPH(4)]

Reaction of Co(O(2)CMe)(2) . 4H(2)O with an excess of PEt(3) and H2S afforded the novel diamagnetic octahedral cluster [Co-6(mu(3)-S)(7)(mu(3)-H)(PEt(3))(6)](+) together with a minor amount of the known paramagnetic isostructural [Co-6(mu(3)-S)(8)(PEt(3))(6)](+). Solid solutions of the two cluster cations have been isolated as the BPh(4)(-) salt. The deuteriated derivative [Co-6(mu(3)-S)(7)(mu(3)-D)(PEt(3))(6)](+) has been prepared for comparison. The compounds have been characterized by H-1, P-31 NMR, mass spectrometry and electrochemical measurements. The molecular structure of a sample of composition [Co-6(mu(3)-S)(7)(mu(3)-H)(PEt(3))(6)](0.7)[Co-6(mu(3)-S)(8)(PEt(3))(6)](0.3)[BPh(4)] has been determined by single-crystal X-ray diffraction. It consists of a solid solution of [Co-6(mu(3)-S)(7)(mu(3)-H)(PEt(3))(6)](+) and [Co-6(mu(3)-S)(8)(PEt(3))(6)](+). The cation [Co-6(mu(3)-S)(7)(mu(3)-H)(PEt(3))(6)](0.7)[Co-6(mu(3)-S)(8)(PEt(3))(6)](+)(0.3) is isostructural with the series [M(6)(mu(3)-S)(8)(PEt(3))(6)](n+), having a metal-metal separation averaging 2.739(8) A. The electronic structure of the novel hydridoderivative has been investigated through density functional calculations.