Energy Transfer in Li*(3p)−H<INF>2</INF> Collisions

The direct collisional energy transfer process Li*(3p) + H<INF>2</INF> → Li*(3s) + H<INF>2</INF> is investigated under gas cell conditions. In particular, we measured the nonreactive far-wing absorption profile of LiH<INF>2</INF> 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 LiH<INF>2</INF> 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.