Classical and quantum studies of the photodissociation of a HX (X=Cl,F) molecule adsorbed on ice

S. Woittequand (1) , D. Duflot (1) , M. Monnerville (1) , B. Pouilly (1) , C. Toubin (1) , S. Briquez (1) , H.-D. Meyer (2)

1 PhLAM - Laboratoire de Physique des Lasers, Atomes et Molécules - UMR 8523
2 Theoretische Chemie

The photodissociation dynamics of a HX (X=Cl,F) molecule adsorbed on a hexagonal ice surface at T=0 K is studied using time-dependent quantum wave packets and quasiclassical trajectories. The relevant potential energy surfaces are calculated using high-level ab initio methods. We present here two dimensional calculations for the dynamics of the hydrogen photofragment for both HCl and HF molecules. The purpose of this paper is to compare the photodissociation dynamics of the two molecules which are adsorbed on the ice surface with different equilibrium geometries. The total photodissociation cross section and the angular distribution are calculated. The comparison with classical trajectory calculations provides evidence for typical quantum effects and reveals rainbow structures.

Mots clés: Diffuse spectra; predissociation photodissociation; Potential energy surfaces; Ab initio calculations; General molecular conformation and symmetry; stereochemistry

Domaines: Chimie-Physique [physics.chem-ph]

S. Woittequand, D. Duflot, M. Monnerville, B. Pouilly, C. Toubin, et al.. Classical and quantum studies of the photodissociation of a HX (X=Cl,F) molecule adsorbed on ice. Journal of Chemical Physics, 2007, 127, pp.4717. ⟨10.1063/1.2799519⟩. ⟨hal-00880776⟩