Pressure dependence of low-frequency light scattering in carbon disulfide

The pressure dependence of low-frequency vibrational density of states, ρ(ω), for liquid and crystalline carbon disulfide (CS2) is determined by measurement of light-scattering spectra using diamond anvil cell. In the liquid, a broad band is observed and in crystalline CS2, sharp peaks are observed under high pressure. Molecular dynamics calculations predicted that these sharp spectra come from the librational mode. We indicate experimentally that the origins of spectra obtained in liquid and crystalline CS2 are the same.