The dissociation adiabaticity parameter and the strong field dissociation of HCl+.
In earlier work on H2+, we showed how a dissociation adiabaticity parameter, gammaDv identical with (Dv/2Upm)(1/2) (Dv is the dissociation energy from vibrational state v and U(pm) is the molecular ion system's ponderomotive energy), proposed by Walsh et al., can be modified and be a useful indicator of the strong field dissociation regime for a homonuclear diatomic. In the case of H2+, the new adiabaticity parameter, gamma(mol), indicates when a dissociation process can be most easily described as multiphoton above-threshold dissociation (gamma(mol)>1) and when it is better described using barrier-suppressed dissociation (gamma(mol)<1). In the case of a heteronuclear diatomic like HCl+, different electronic states can lead to different dissociation product channels to which are ascribed different gamma(mol) values. We show for a wide range of laser wavelengths and intensities that this adiabaticity parameter successfully predicts the type of dissociation dynamics (multiphoton above-threshold dissociation versus barrier-suppressed dissociation) on each electronic potential curve. We also discover that the dynamics in one electronic state can influence the dynamics in another at the same laser wavelengths and intensities, overriding the predictive capability of an adiabaticity parameter defined for a particular electronic state. Reasonable physical explanations are provided for these overriding cases.
Department of Chemistry, Queen's University, Kingston, Ontario K7L 3N6, Canada.
Jeffrey T
JT
Paci
David M
DM
Wardlaw