Quantum functional sensitivity analysis for the 3-D (J = 0) H + H2 reaction



The sensitivity of state-to-state transition probabilities for the 3-dimensional H + H2 hydrogen-exchange reaction (at zero total angular momentum) has been investigated with respect to variations in the interaction potential. Several regions of configuration space where the dynamics is highly sensitive to inaccuracies in the potential have been identified. These regions of importance vary with collision energy, but do not change as dramatically as the previously studied [J. Chem. Phys. 97, 6226 (1992)] collinear case. Near the reaction threshold, the dynamics is most sensitive to the saddle point region as expected. At higher energies (about 1.0 to 1.5 eV), however, the inner corner of the potential, where the dynamics “cuts the corner” in going from reactant to product arrangements, is most important for collinear geometries, and the outer corner, where the H3 conformation is more compact than the transition state conformation, is most important for bent geometries. Surprisingly, the region of the potential traversed by the minimum energy path across the saddle point region has rather insignificant sensitivities at these higher energies. © 1993 John Wiley & Sons, Inc.