Raman and resonance-Raman studies of platinum group tetrathiomolybdates and tetrathiotungstates

Abstract

The Raman and resonance-Raman spectra of the ions [M′(MS₄)₂]^2–(M′= Ni, Pd, or Pt; M = Mo or W) at ca. 80 K have been studied with excitation lines ranging from 647.1 to 337.5 nm. The bands assigned to the ν( M–S_b), ν(M–S_t), and ν(M′–S)(b = bridging, t = terminal) fundamentals all show resonance enhancement, and overtone progressions are observed in the resonance-Raman spectra. The nature of these progressions depends on the line used to excite the Raman spectrum. From excitation profile studies, assignments are suggested for the resonant electronic absorption bands.