Vibrational analysis of chloroethane-2-d1

The i.r. and Raman spectra of gaseous and liquid samples of chloroethane-2-d 1 have been observed in the region between 4000 and 200 cm −1 . All of the observed i.r. and Raman active fundamentals have been assigned for the trans and gauche geometrical conformations. The assignments of the fundamentals to the conformers are supported by a normal coordinate calculation, employing the valence force-field of Dempster and Zerbi, which reproduces the observed frequencies with an RMS deviation of 9.5 cm −1 . The molecular absorption features pumped by the CO 2 laser are assigned as the ν 8 and ν 9 modes of the gauche conformer.