Three pulse photon echo studies of nondipolar solvation: Comparison with a viscoelastic model

Delmar S. Larsen, Kaoru Ohta, Graham R. Fleming
1999 Journal of Chemical Physics  
Three pulse stimulated photon echo peak shift ͑3PEPS͒ measurements were used to probe the solvation of a quadrupolar solute in three room temperature nondipolar solvents; benzene, CCl 4 , and CS 2 , and the results were compared with those for two polar solvents, methanol and acetonitrile, and one weakly polar solvent, toluene. Our data reveal three distinct solvent dynamical time scales; a sub-100 fs ultrafast component attributed to inertial motions, a slow ͑ϳ2-3 ps͒ component attributed to
more » ... ent attributed to structural relaxation, and an intermediate time scale ͑ϳ600 fs͒ of uncertain origin. The six solvents were chosen to reflect a range of possible interactions, but exhibit similar dynamics, suggesting that similar mechanisms may be at work or that different mechanisms may exist, but occur on similar time scales. A viscoelastic continuum solvation model proposed to describe nonpolar solvation ͓J. Phys. Chem. A 102, 17 ͑1998͔͒ was used for a preliminary analysis of our data.
doi:10.1063/1.480240 fatcat:zfz7pq6czffvvkb4uu6jj5zmya