The Vibrational Spectra of Sulphuryl and Thionyl Halides

New assignments are proposed for the fundamental frequencies of SOF 2 , SOCl 2 , SO 2 Cl 2 , SO 2 F 2 , and SO 2 FBr, based on new measurements of the Raman spectrum of SO 2 Cl 2 and previous measurements of the infrared and Raman spectra of these molecules. The fundamental frequencies of these molecules are found to be related to each other and to those of similar molecules when the normal modes are described in terms of characteristic vibrations of the SO, SO 2 , S(Hal), and S(Hal) 2 groups.