Interaction induced effects in the nonlinear Raman response of liquid CS2:A finite field nonequilibrium molecular dynamics approach

The third- and fifth-order time-domain Raman responses of liquid carbon dis ulfide have been calculated, taking local field effects into account throug h the dipole-induced dipole approximation to the polarizability. The third- order response is shown to be in excellent agreement with experimental data . The calculated two-dimensional shape of the fifth-order response is compa red with recently reported experimental observations of what is claimed to be pure fifth-order response. Considerable discrepancies are observed which might be explained by contamination of the experimental results with seque ntial and especially parallel third-order cascaded Raman response. A new ch oice of polarization conditions is proposed, which increases the discrimina tion against these unwanted cascading effects, as compared to the previousl y discussed fully polarized and magic angle conditions. (C) 2001 American I nstitute of Physics.