Vibrational spectra and normal coordinate analysis of germylazide-do and -d3

The infrared spectra (4000–20 cm^?1) of gaseous and solid GeH₃NNN and GeD₃NNN and the Raman spectra (3000–0 cm^?1) of liquid and solid GeH₃NNN and GeD₃NNN have been recorded. The vibrational spectrum has been assigned on the basis of C_s symmetry. The GeNN bend was observed in the Raman spectrum of the gas at ~150 cm^?1; however, the frequency of the GeH₃ torsion could not be determined. A normal coordinate calculation has been carried out by utilizing a modified valence force field. The GeN stretching force constant was found to have a significantly smaller value than the corresponding force constant in GeH₃NCO and GeH₃NCS. A considerable amount of mixing was found between the GeN stretch and the NNN in-plane bend. The frequencies of the normal modes and the normal coordinate analysis of GeH₃NNN are discussed in view of the recent results reported for GeH₃NCO and GeH₃NCS.