Massively parallel Hamiltonian action in pseudospectral algorithms applied to quantum dynamics of laser induced desorption

The Hamiltonian action upon a wavefunction is the basic operation in iterative propagation schemes. Aiming at high-dimensional quantum dynamics, we introduce a parallel algorithm for a Hamiltonian action utilizing pseudospectral schemes on multidimensional grids. This algorithm is exemplified for a six-dimensional (6D) quantum dynamical system described in Fourier coordinates. The performance outcome of our parallel implementation is revealed by an almost linear overall scaled speedup that is only limited by present hardware resources. Our parallelization strategy is realized in ab initio four-dimensional (4D) quantum dynamical studies investigating the lateral dynamics of CO photodesorbing from a Cr(2)O(3)(0 0 0 1) surface. (C) 2004 Elsevier B.V. All rights reserved.