Beyond the time-dependent Hartree grid approximation for curve-crossing problems

Abstract

A new "configuration-interaction" method is presented which extends the single-surface time-dependent Hartree grid (TDHG) approximation into a formally exact algorithm for obtaining multidimensional quantum wave-packet dynamics on nonradiatively coupled electronic potential surfaces. As a numerical example, photofragmentation cross sections are computed for a two-degree-of-freedom model of direct dissociation. For systems prepared in vibrationally excited states of the ground electronic potential the TDHG approximation fails due to "direct correlation" effects, while our method provides accurate results. © 1992 American Institute of Physics.