Temperature-dependent optical Kerr effect spectroscopy of chloroform in restricted geometries Original Research Article

Optical Kerr effect spectroscopy has been used to study the orientational dynamics of chloroform confined within nanoporous glasses of various pore sizes. The decays can be fit well to the sum of two exponentials, the fastest of which has a decay time that matches that of the bulk liquid. Based on these data, we have quantified the surface population and the dynamics of the confined liquid. We have also studied the dynamics of the Raman-active degenerate CCl3 deformation mode at 262 cm−1 and the symmetric CCl3 stretch at 365 cm−1, both of which show shifts to higher frequency in confinement. The shifts decrease as the temperature decreases. Pure dephasing and population relaxation at the pore walls appear to dominate the spectral line shapes at lower temperatures, resulting in a decrease in the dephasing time in confinement. At higher temperatures, the line shape is dominated by rotational broadening.