CORIOLIS-INDUCED VIBRATIONAL-ENERGY TRANSFER IN D2CO-D2CO COLLISIONS .2. A SEMICLASSICAL SUDDEN APPROXIMATION

Recent experimental studies of vibrational energy transfer in D 2CO-D2CO collisions have demonstrated extraordinarily high cross sections for an intramolecular V-V process in which a vibrational quantum is transferred between the two coriolis-coupled modes ν4 and ν6. In this paper a simple semiclassical theory of this process is presented. The theory combines a resonance Hamiltonian originally derived by Burleigh, Mayrhofer, and Sibert, and by Gray and Davis, with a classical-path treatment of translation. With the aid of a time-dependent sudden approximation, applied not to molecular rotation but to the 3.5 cm-1 energy gap between perturbed molecular eigenstates, opacity functions, and absolute cross sections can be calculated in closed analytic form. Agreement with experiment is surprisingly good. © 1990 American Institute of Physics.