ITERATIVE DIAGONALIZATION WITHIN THE MULTI-CONFIGURATIONAL TIME-DEPENDENT HARTREE APPROACH - CALCULATION OF VIBRATIONALLY EXCITED-STATES AND REACTION-RATES

An iterative diagonalization scheme for operators involving wavepacket propagations employing the multi-configurational time-dependent Hartr ee (MCTDH) approach is presented. The scheme is based on a Lanczos-typ e recursion relation, which is modified to account for the different s ets of single-particle functions employed in different MCTDH wavefunct ions. Two possible applications are given: the calculation of energies and eigenfunctions of vibrationally excited states, and the direct ca lculation of thermal rate constants. The electronic ground state of CH 3I including four vibrational coordinates and the collinear H + H-2 re action have been used as testing examples.