Shapes of Fundamental Bands of Liquid Carbon Disulfide, Vibrational and Reorientational Relaxations

The shapes and intensities of the fundamental bands, v2 (the CSC bending) and v3 (the C–S antisymmetric stretching), were measured for liquid carbon disulfide and its chloroform solutions. The intensity data were corrected for the effect of the dielectric field at each frequency. The analyses of the v2 and v3 bands indicate that the band-widths of liquid carbon disulfide can not be explained only in terms of reorientational relaxation. It is also shown that the vibrational relaxation of the resonance type can well explain the concentration dependence of the observed band-widths. The magnitudes of the vibrational and reorientational relaxations obtained from the bandshape analyses are given. It is emphasized that the measurement of the absolute intensity is indispensable for the analyses of the infrared-band shapes of condensed phases.