Trajectory Surface Hopping Study of the Li + Li 2 (XΣ g + ) Dissociation Reaction

Trajectory surface hopping calculations are reported for the Li + Li 2 (X 1 Σ g + ) dissociation reaction over the range of translational energies 13 ≤ E tr /kcal mol -1 ≤ 80. Both potential energy surfaces for ground doublet Li 3, which have been modeled from the double many-body expansion method (DMBE III), have been employed in the dynamics calculations. For the initial internal state ( v = 0, j = 10), the behavior of the dissociative cross sections as a function of translational energy shows that nonadiabatic effects are important over the whole range of energies studied. Concerning the role of initial vibration, it has been found that, for E tr = 25 kcal mol -1 and j = 10, the adiabatic dissociative cross sections are enhanced as v increases from 0 to 20, while the nonadiabatic ones just slightly increase with the vibrational quantum number.