INFRARED-SPECTRA OF NBCL5 AND MOCL5 IN THE GAS-PHASE

The infrared (IR) spectra of the vapour phases above NbCl5 and MoCl5 h ave been studied at elevated temperatures. All five IR-active fundamen tals of NbCl5(g) of D3h Symmetry have been observed. In the vapour abo ve MoCl5 two different species have been found. At the beginning of th e experiment an oxychloride species was formed due to some oxygen impu rity which is concluded to be MoOCl3. Subsequently, MoCl5(g) was forme d for which four IR-active fundamentals have been observed, the spectr um being consistent with a D3h symmetry also.