Abstract

Critical to the understanding of condensed phase reaction dynamics is the understanding of a solvent's response to and influence on the system dynamics. Although models of a solvent's vibrational and orientational dynamics can be tested against infrared and Raman studies of the neat solvent, thus far this has not proven fruitful because the influence of nuclear dynamics on infrared absorption, optical Kerr effect, spontaneous Raman and CARS spectra is usually masked by inhomogeneous broadening. However, valuable information about the solvent nuclear dynamics can be extracted from nonlinear spectroscopies such as infrared and Raman echoes. Using the formalism of Tanimura and Mukamel,¹ we have calculated the 3rd, 5th, and 7th order Raman spectra for liquid water employing a multimode Brownian oscillator model to represent the water modes. This model is expected to be appropriate for liquid water because it accounts for nuclear dynamics occurring on a finite time scale, extrapolating continuously between the limiting cases of homogeneous and inhomogeneous nuclear dephasing.

© 1994 Optical Society of America