Vibrational spectra and internal rotation of chlorophosphines

Abstract

The present paper is devoted to the investigation of i.r. spectra (400-4000 cm-1) of ClCH2PCl2, C2H5PCl2, (C2H5)2PCl, Ph(C2H5)PCl in gaseous, liquid and crystalline states and of Raman spectra of ClCH2PCl2 and C2H5PCl2 in liquid state. The influence of temperature on i.r. spectra has been studied. The normal co-ordinate analysis of different conformers of CH3PCl2, ClCH2PCl2 and C2H5PCl2 has been carried out. The experimental material and normal co-ordinate analysis shows that in ClCH2PCl2, C2H5PCl2 and (C2H5)2PCl the internal rotation around the PC bond is possible and that these molecules are present in a liquid as a mixture of two rotational isomers. The terms Vk in the decomposition of potential energy of internal rotational into Fourier series has been evaluated in the approximation of the harmonic oscillator. © 1976.