COMBINING THE DISCRETE VARIABLE REPRESENTATION WITH THE S-MATRIX KOHNMETHOD FOR QUANTUM REACTIVE SCATTERING

In order to reduce the memory requirements of quantum reactive scatter ing calculations based on delocalized basis sets, we use a discrete ba sis in a single interaction region coordinate system, resulting in a s parse Hamiltonian matrix. The resulting set of linear equations is sol ved via an iterative method which exploits their sparsity. Other impor tant features of our formalism are the use of a truncated grid and dis torted waves used to shrink the interaction region, and therefore the basis size. We demonstrate the method and assess its efficiency for th e reaction D+H-2 --> DH+H, at a total energy of 0.9 eV and zero total angular momentum (J=0).