CONVERGED QUANTUM-MECHANICAL CALCULATIONS OF ELECTRONIC-TO-VIBRATIONAL, ROTATIONAL ENERGY-TRANSFER PROBABILITIES IN A SYSTEM WITH A CONICAL INTERSECTION

We present quantum-mechanical transition probabilities for the process Na(3p2P) +H2(nu0 = 0,j0 = 0, 2) --> Na(3s2S) + H-2(nu',j') with zero total angular momentum where nu0, j0, nu', and j' are initial and final vibrational and rotational quantum numbers. These calculations involve two coupled potential energy surfaces at a total energy of 2.431 eV, and the excited state has energetically accessible geometric configurations with H-H internuclear distances 2.7 times larger than the H-2 equilibrium internuclear distance - which makes converged quantum-mechanical calculations very difficult. Convergence is demonstrated by obtaining the same results using two entirely different methods - R matrix propagation and the outgoing wave variational principle.