Energy transfer in Li*(3p)-H2 collisions

The direct collisional energy transfer process Li*(3p) + H2 → Li*(3s) + H2 is investigated under gas cell conditions. In particular, we measured the nonreactive far-wing absorption profile of LiH2 complexes by monitoring the Li(3s) → Li(2p) fluorescence at 812.6 nm. Strong satellite structures are observed at around 700 cm-1 in the blue wing and 162 cm-1 in the red wing of the LiH2 profile. The experimental results are in agreement with ab initio theoretical predictions, which showed a strong probability of a diabatic transition making the 3p-3s quenching easy. © 2000 American Chemical Society.