Synthesis and spectroscopic identification of a mu-1,2-disulfidodinickel complex.

Reduction of elemental sulfur by a monovalent nickel precursor leads to a trans-1,2-mu-disulfidodinickel(II) complex assigned based on a combination of advanced spectroscopic methods in conjunction with density functional theory calculations. The disulfido linkage is characterized by an intense optical S --> Ni charge transfer transition at 650 nm, which causes a significant distortion of the Ni(2)S(2) core along an isotope-sensitive v(S-S) mode at 474 cm(-1), as demonstrated by the resonance Raman excitation profile of this vibrational feature.