Quantal treatment of the low energy collision of Ne*(3P0,2) with H2(1∑+g,v=0).

A close-coupling channel computation of Ne*(3P0,2)–H2 (1∑+g, v=0) collisions, using the ab initio potentials given in a preceding paper, is reported. The molecule is considered as a rigid rotator. The autoionizing character of states dissociating into Ne* (2p53s)+H2 is ignored. Consequently Penning and chemi-ionizations are not considered. Combined fine structure and rotational transitions are the only inelastic channels expected. By means of a deflation procedure, collision channels leading to Ne*(1P1) are shown to be negligible in the present energy range (E≤175 meV). The ‘‘fragment’’ basis (i.e., Ne*+H2 at infinite R) is adapted to the collision treatment since all off-diagonal elements of the electronic Hamiltonian, including the spin–orbit interaction (static couplings) are small. The coupling of angular momenta ( j1=0,1,2 of Ne*, j2=0,2 of para-H2, 1 of ortho-H2, l for the relative motion) leads to 27 coupled equations for ortho-H2 and 54 equations for para-H2, for each value of the total angular momentum J. These equations are solved by using the algorithm of Gordon, and the 81×81 S matrix is derived. The rotational excitation ( j2=0→2) probability takes a maximum value of the order of 10-2 at J≊15. [ABSTRACT FROM AUTHOR]