Mv. Basilevsky et al., NONEQUILIBRIUM INTERLEVEL TRANSITIONS IN CONDENSED-PHASE FAR AWAY FROM THE AVOIDED CROSSING REGION, Chemical physics, 235(1-3), 1998, pp. 281-296
The quantum-classical dynamics of interlevel transitions in condensed
phase is considered in a special case when the transitions are localiz
ed far away from the avoided crossing region on the ground state free
energy surface. A resonance case of a transition is studied when the t
wo energy levels have the same shapes and equilibrium positions and ar
e only shifted on the energy axis. For this simplified model the analy
tical expression for the non-equilibrium rate constant was derived sta
rting from the multichannel Smoluchowski equations in the high-tempera
ture limit. A deficiency of the existing multichannel diffusion theory
is revealed and discussed. The illustrative calculations were perform
ed for the model of proton transfer (PT) reaction in condensed phase.
The results support the conclusion that the earlier proposed two-state
model exaggerates the role of tunneling in PT processes. (C) 1998 Els
evier Science B.V. All rights reserved.