Accurate calculation of state-to-state tetraatomic reaction cross sections using row-orthonormal hyperspherical coordinates

PHYS 424

Desheng Wang, and Aron Kuppermann, Division of Chemistry and Chemical Engineering, California Institute of Technology, 1200 E. California Bl, Pasadena, CA 91125
A general approach has recently been developed for performing ab initio calculations of state-to-state reaction cross section calculations for tetraatomic systems. Row-orthonormal hyperspherical coordinates (ROHC) are used in the strong interaction region of configuration space and Delves hyperspherical coordinates in the weak interaction region. The scattering wave function is expanded in local hyperspherical surface functions (LHSF). In the strong interaction region, these are calculated by an expansion in analytical hyperspherical harmonics. For each total angular momentum J, irreducible reprentation Γ and inversion parity Π, the time-independent hyperradial matrix Schrödinger equation is propagated from small to large values of the hyperradius. After projection onto the isolated atom-triatom or diatom-diatom wave functions, the scattering matrices SJΠΓ are obtained. From them, state-to-state cross sections, including m (i.e., orientation) states, are obtained. The formalism will be presented as well as results obtained so far for the H2+OH → H2O+H reaction.

Poster Session
7:30 PM-10:00 PM, Wednesday, 13 September 2006 Moscone Center -- Hall D, Poster

Division of Physical Chemistry

The 232nd ACS National Meeting, San Francisco, CA, September 10-14, 2006