Vibrational Linewidth-Broadening Mechanisms in Liquids Revealed by the Separation of the Rapidly and Slowly Varying Intermolecular Forces

摘要

The mechanisms for vibrational linewidth broadening in liquids are investigated using the temperature dependence of coherent picosecond Stokes scattering. Both rapidly varying repulsive and slowly varying attractive intermolecular forces are determined to cause significant linewidth broadening. The liquid's local number density distribution width is shown to play an important role in inhomogeneous linewidth broadening. This is in agreement with both the model of George, Auweter and Harris and the recent theory by Schweizer and Chandler. (ERA citation 07:044295)