PHOTOFRAGMENT SPECTROSCOPY AND DISSOCIATION DYNAMICS OF N2(2+) - A 1-PI-U-X1-SIGMA-G+

The 9-0 and 9-1 transitions of the A 1PI(u)-X 1SIGMA(g)+ system of N-2(2+) have been observed by fast ion beam photofragment spectroscopy. Multireference configuration interaction ab initio calculations predict upsilon'=8 to be the highest bound level which seemed to be supported by experimental evidence. The dominant predissociation mechanism for the upsilon'=9 level appears to be through tunneling, unlike the upsilon'=6, 7, and 8 levels, which show an e/f symmetry-dependent electronic predissociation. Calculated tunneling lifetimes from our own modified A 1PI(u) state potential gives good agreement with the experimental lifetimes. In addition to the 9-1 and 9-0 bands, we have also measured the previously unobserved 7-0 and 8-0 rovibronic transitions thus extending Cosby, Muller, and Helm's study to the blue [Phys. Rev. A 28, 766 (1983)]. Molecular constants have been determined for the upsilon = 0 of the X 1SIGMA(g)+ state and upsilon = 7, 8, and 9 of the A 1PI(u) state.