Temperature-dependent vibrational relaxation in isotopically mixed molecular crystals by picosecond CARS
Journal
Chemical Physics Letters
Journal Volume
187
Journal Issue
3
Pages
208-214
Date Issued
1991
Author(s)
Abstract
Temperature-dependent dephasing of 511, 766 and 1385 cm-1 modes in the mixed crystals of naphthalene and perdeuteronaphthalene at various isotopic levels have been studied by picosecond CARS in the region of 6-130 K. In general, adding the isotope shows a significant effect on the low-temperature decay time. However, a small effect on the temperature dependence is observed in the Arrhenius plots of ln[Δν(T)-Δν(6 K)] versus 1/T for all three modes. This behavior is described by a large change of the thermally activated phonon density of states at low temperature, but by a small change as temperature increases. © 1991.
Type
journal article