POTENTIAL-ENERGY SURFACES FOR POLYATOMIC REACTIONS BY INTERPOLATION WITH REACTION-PATH WEIGHT - CH2OH-]CHO++H-2 REACTION()

An improved algorithm to construct molecular potential energy surfaces for polyatomic reactions is presented. The method uses the energies, gradients, and Hessians, which can be obtained from ab initio quantum chemical calculations. The surface is constructed by interpolating the local quadratic surfaces with reaction path weights. The method is te sted with a five-atom reaction system for which an analytic potential energy surface has been reported together with classical trajectory re sults. An excellent agreement is achieved for energy partitioning in p roducts obtained by trajectory calculation on the original analytic an d interpolated surfaces. Reduction of error caused by the use of the r eaction path weight is explained. (C) 1997 American Institute of Physi cs.