The intermolecular interaction mechanisms in liquid CS_2 at 295 and 165 K probed with two-dimensional Raman spectroscopy

摘要

Two-dimensional Raman spectroscopy is used to probe the intermolecular interaction dynamics of CS_2 at 295 and 165 K. The influence of nonlinear polarizability and liquid anharmonicity on the observable is discussed. It is found that the response at both temperatures is dominated by the nonlinear polarizability, which is most likely due to interaction-induced effects. A model using three Brownian oscillators to represent the collective motions on three time scales is unable to reproduce the 295 K data. At low temperature, the model presumably works better as a result of the time-scale separation between the inertial and diffusive dynamics.