Journal of Physical Chemistry A, Vol.101, No.20, 3641-3645, 1997
Ultrafast Optical Kerr-Effect and Solvation Dynamics of Liquid Aniline
Femtosecond optically heterodyne detected optical Kerr effect (OHD-OKE) measurements have been made on liquid aniline. These are contrasted with solvation dynamics measurements made earlier. The OHD-OKE data in the frequency domain can be analyzed in terms of three components : a low-frequency diffusional part; a collisional part; an underdamped intermolecular mode. The latter is quite intense, suggesting strong intermolecular interactions and a relatively high degree of structure in liquid aniline. When the solvation dynamics calculated from the pure liquid data are compared with those measured directly, the agreement beyond 1 ps is good. This result suggests that it is possible to use experimental data obtained on the pure solvent dynamics to model the solvation dynamics response. However, the agreement is not as good at very early times. While this may simply reflect the lower time resolution of solvation dynamics experiments compared to OHD-OKE experiments, we speculate that the differences could also result from either fundamental differences in the measured solvation dynamics and those calculated from OHD-OKE data or a perturbation of the intermolecular interactions in liquid aniline by the solute.
Keywords:ELECTRON-TRANSFER FASTER;SOLVENT RELAXATION;FEMTOSECOND DYNAMICS;ACETONITRILE;SPECTROSCOPY;WATER;DEPENDENCE;RESPONSES;FORMAMIDE;MOTIONS