A three dimensional quantum mechanical theory to treat tetrahyphen;atom reactions: Statehyphen;tohyphen;state cross sections for the H2+OHrarr;H2O+H process

摘要

A quantum mechanical approach to treat diatomndash;diatom exchange processes of the typeAB+CDrarr;ABC+Dis presented. The approach is based on three types of wave functions psgr;0ngr;, psgr;0lgr;, and khgr;, where the first two are (asymptotic) elastic distorted wave functions for the two arrangement channels ngr; and lgr;, and khgr; is a short range (square integrable) wave function describing the system in the close interaction region. The functions psgr;0ngr;and psgr;0lgr;are presented within thejzapproximation, and to calculate khgr;, a perturbativehyphen;type Schrouml;dinger equation which contains negative imaginary potentials (to form absorbing boundary conditions) is solved. The variationally stable solution is obtained employing Gaussians and local adiabatic basis sets. The actual calculation of khgr; is done employing the quasibreathing sphere model, where the relevant angular coordinates are selected randomly (about 50 sets like that were used) employing a Monte Carlo approach. With this approach, most detailed statehyphen;tohyphen;state cross sections were calculated for the reaction H2(n1=0,j1=0)+OH(n2=0,j2=0)rarr;H2O(vjmacr;vKOHgr;K)+H, where (vjmacr;v) are the usual vibrationalhyphen;bending states of the water molecule, andKand OHgr;Kare, respectively, the overall rotational quantum number and the corresponding magnetic component. The results were compared with those due to other treatments and with experiment.