In earlier work on H_2~+ [J.T.Paci and D.M.Wardlaw,J.Chem.Phys.119,7824 (2003)],we showed how a dissociation adiabaticity parameter,gamma_Dident to(D_v/2U_(pm))~(1/2) (D_v is the dissociation energy from vibrational state v and U_(pm) is the molecular ion system's ponderomotive energy),proposed by Walsh et al [T.D.G.Walsh,L.Strach,and S.L.Chin,J.Phys.B 31,4853 (1998)],can be modified and be a useful indicator of the strong field dissociation regime for a homonuclear diatomic.In the case of H_2~+ ,the new adiabaticity parameter,gamma_(mol),indicates when a dissociation process can be most easily described as multiphoton above-threshold dissociation (gamma_(mol)>l) 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.
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