Bis(sulfinylamino)selane, Se(NSO)(2): between S(NSO)(2) and Te(NSO)(2) in theoretical and spectroscopical considerations

Vibrational spectra of bis(sulfinylamino)selane, Se(NSO)(2), together with the evaluation of its pre-resonance Raman effect, demonstrate that the C-2v point group does not change upon electronic excitation. Computational chem istry results agree with the Z configuration of the molecule reported by X- ray analysis and that of R-N=S=O compounds investigated so far. Treatments using relativistic effects at the Se atom give comparable results to those obtained using ab initio (HF and MP2 levels of approximation) and density f unctional theory calculations employing a 6-31 +G* basis set. Excited state geometry calculations are performed using the time-dependent theory of spe ctroscopy. Three dimensionless displacements calculated with this model fit not only the experimental Raman excitation profiles, but the behaviour of two further overtone and combination modes. (C) 1999 Elsevier Science B.V, All rights reserved.