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) TDSCF 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.

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