CALCULATION OF H-2 AND H+D-2 REACTION PROBABILITIES WITHIN THE MULTICONFIGURATION TIME-DEPENDENT HARTREE APPROACH EMPLOYING AN ADIABATIC CORRECTION SCHEME(H)

The multiconfiguration time-dependent Hartree (MCTDH) method is employ ed to calculate initial-state selected reaction probabilities for the two isotopic reactions H+H-2(D-2) with initial states v=0, j=0-3 and t otal angular momentum J=0. To compute the reaction probabilities, an i nitial wave packet is prepared and propagated in time employing the re cently developed constant mean-field integrator, thus reducing the com putational effort by an order of magnitude. An adiabatic correction sc heme is introduced which allows the initial wave packet to be moved fr om the asymptotic region of the educt channel close to the interaction region. The calculations are performed on the Liu-Siegbahn-Truhlar-Ho rowitz (LSTH) potential surface which is expanded in products of one-d imensional functions of the Jacobian coordinates. Initial-state select ed reaction probabilities are computed for total energies up to 2.5 eV utilizing a combined flux operator/complex absorbing potential approa ch. (C) 1998 American Institute of Physics.