Synthesis, structure, ESI mass spectrum and magnetic property of a monocationic cluster complex of chromium-sulfide with a hydrido ligand [Cr6S8(H)(PEt3)6](BF4)

A monocationic cluster complex of chromium sulfide [Cr6S8(H)(PEt3)6](BF4) (2) was prepared by the oxidation of the corresponding neutral complex [Cr6S8(H)(PEt3)6] (1) with ferrocenium tetrafluoroborate and was characterized by the single-crystal X-ray structure analysis and ESI (electrospray-ionization) mass spectroscopy. Complex 2 has a Cr6S8 octahedral cluster core that holds an interstitial hydrogen atom. The Cr–Cr bond distances of 2 are ca. 0.2 Å longer than those of the starting neutral cluster 1. Magnetic measurements showed that the elongation of the CrCr bonds in the oxidized cluster 2 causes weakening of antiferromagnetic interaction through these bonds, as compared with the neutral complex 1.