Vibrational spectrum and force constants of the monochlorochromate ion

Abstract

The vibrational spectrum of the ion (CrO 3Cl) − is reported. The Raman spectra were obtained in the red region of the spectrum by excitation with the helium radiations 5875.6 and 6678.2 Å, the infra-red absorption spectrum was investigated over the range 10–32 μ. The spectrum is in full agreement with the expected C 3 v -symmetry of the ion and the observed frequencies have been assigned under this point group. A normal co-ordinate treatment based upon Wilson's - FG-matrix method and a simplified valence force field has been carried out and force constants have been calculated. The stretching frequencies of the ion and the related valence force constants are compared with those of other hexavalent chromium compounds, previously reported by the authors.