Rotational excitation cross sections of para-H2 plus para-H2 collisions.: A full-dimensional wave-packet propagation study using an exact form of the kinetic energy -: art. no. 174311

A full-dimensional quantum dynamical study of the rotational excitation in para-para H-2 + H-2 collisions using the potential-energy surface of Boothroyd [J. Chem. Phys. 116, 666 (2002)] is reported. The multiconfiguration time-dependent Hartree algorithm is utilized to propagate wave packets and the cross sections for collision energies up to 1.2 eV are determined by a flux analysis through the interaction of the wave packet with a complex absorbing potential. Calculations for a collection of total angular momenta up to J = 70 are performed; the missing channels are obtained with a J-interpolation algorithm. (c) 2005 American Institute of Physics.