Abstract
Quasi-classical trajectories have been carried out on a 2-valued surface for the singlet ground state of H2O. The calculated rate constants for both O(1 D) + H2(1Σg +) →OH(2Π) + H(2 S) and D(2 S) + OH(2Π) →H(2 S) + OD(2Π) are in good agreement with experimental values. For D(2 S) + OH(2Π) collisions above 2 eV, O(1 D) can be produced but the probability for this is low.