Nonadiabatic solvation dynamics and decoherence: a molecular<br/><br/>hydrodynamic approach

Thursday, March 5, 2009 - 2:30pm - 3:00pm
EE/CS 3-180
Irene Burghardt (École Normale Supérieure)
We present a recently developed mixed quantum-classical method which accounts
for the evolution of a quantum subsystem coupled to a non-equilibrium
environment (solvent) described in an extended hydrodynamic setting [1].
Starting from a hybrid quantum-classical phase-space distribution, coupled
equations for the quantum-classical local density and momentum density are
derived which feature the characteristic population-coherence coupling of the
nonadiabatic quantum evolution. A generalized free energy functional is
introduced, which is similar to the functionals used in dynamical density
functional theory (DDFT) methods [2] but is adapted to the quantum-classical
setting. The relevant functionals involve two-particle (or, more generally,
n-particle) correlation functions that are constructed from state-specific
microscopic solute-solvent interactions. A microscopic Marcus-type functional
for polar solvation is considered as a special case. The present formulation
is particularly appropriate to describe ultrafast solvation dynamics coupled
with charge transfer, for example in photochemical charge transfer processes.
By the explicit consideration of quantum coherence, the details of population
transfer and its susceptibility to decoherence effects, become amenable to
direct investigation. First numerical examples are presented [3] and the
extension of the formalism beyond the free energy functional formulation are
addressed, in particular in view of including non-equilibrium solvent

[1] I. Burghardt and B. Bagchi, Chem. Phys. 329, 343 (2006).

[2] B. Bagchi and A. Chandra, Adv. Chem. Phys. LXXX, 1 (1991);
U. Marini Bettolo Marconi and P. Tarazona, J. Chem. Phys. 110, 8032 (1999);
A. J. Archer and R. Evans, J. Chem. Phys. 121, 4246 (2004).

[3] P. Ramanathan, S. Parry, S.-L. Zhao, K. H. Hughes, and I. Burghardt,
to be submitted.