PUB - Publikationen an der Universität Bielefeld

Fourier transform Raman spectra of the prototype, triangular, transition metal-sulfur cluster anion [Mo-3(S-2)(6)S](2-) were recorded at pressures up to 60 kbar with the aid of a diamond-anvil cell (DAC). The pressure dependences (partial derivativen/partial derivativep) of the Raman bands indicate a structural change at around 10-15 kbar. The S-S stretching mode for the bridging disulfide ligands exhibits a slightly negative partial derivativev/partial derivativep value (-0.08), suggesting that S-S bonds are weakened, i.e. activated, at high pressures. This pressure-induced activity parallels the observed nucleophilic substitution reactivity of the S2 groups in this molybdenum cluster anion. In view of this, a preliminary investigation of the reaction between [Mo-3(S-2)(6)S](2-) and CN- was undertaken in the solid state in the DAC under high pressure. Copyright (C) 2002 John Wiley Sons, Ltd.