Raman intensities of gas phase methyl chloride and deuterated derivatives, force constants and bond polarizability parameters

The absolute Raman intensities of all fundamental bands of CH 3 Cl, CD 3 Cl, CH 2 DCl and CHD 2 Cl have been measured in the gas phase, with an estimated accuracy of ∼ 10%. Using these data, and the most recently published vibration‐rotation data on these molecules, a refinement of the potential function has been carried out, and the results compared to the previous force field for methyl chloride. The derivatives of the molecular polarizability with respect to the symmetry coordinates have also been calculated, and an analysis has been performed of these magnitudes in terms of the bond polarizability theory.