Vibrational predissociation of highly vibrationally excited He…I 2 VDW molecule. A quasiclassical trajectory calculation.

Abstract

We apply a quasiclassical trajectory method to treat vibrational predissociation of the van der Waals molecule He…I 2(B 3π) in the range of high initial vibrational excitation of I 2, 50 ⩽ v 1 ⩽ 63. The vibrational predissociation rates, as a function of v 1, shows a behaviour in good agreement with the recent experimental data. A peaking of that function is found at v 1 ⋍ 56. The propensity rule of the lost of one vibrational quantum by the I 2 in the process, established in a lower diatomic vibrational excitation range, is broken in the high range studied here. Also, because the small rotation excitation of the I 2 fragment obtained, the He…I 2 vibrational predissociation can be considered as a nearly V-T process.