Quantum molecular dynamics by a perturbation-corrected time-dependent self-consitent-field method

A new method is presented for calculating the quantum dynamics of processes in polyatomic systems. The approach uses the time-dependent self-consistent-field (TDSCF) approximation, which treats each mode as moving in a time-dependent mean field. The new method corrects the TDSCF by a perturbation-theoretic algorithm. The method is tested agains numerically exact calculations for vibrationally inelastic He + H₂ collisions, and for reactive H + H₂ scattering. Very good agreement was found with the exact results. Major improvement was obtained over (uncorrected) TDSCF. The method is computationally efficient, practically applicable to systems of many degrees of freedom.