Time-dependent self-consistent field (TDSCF) approximation for a reaction coordinate coupled to a harmonic bath: Single and multiple configuration treatments

This paper explores the usefulness of the time-dependent self-consistent field (TDSCF) approximation for treating the dynamics of a reaction coordinate coupled to a bath of harmonic degrees of freedom. The reaction coordinate is a one-dimensional double well potential, typical of a hydrogen atom isomerization process. The standard (i.e., one configuration) TDSGF approximation is found to provide a very poor description of the effect of coupling to the bath on the isomerization rate. A multiconfiguration (MC-TDSCF) treatment is thus developed and found to provide a much improved description.