Quantitative theory-versus-experiment comparison for the intense laser dissociation ofH2+

Abstract

A detailed theory-versus-experiment comparison is worked out for H + 2 intense laser dissociation, based on angularly resolved photodissociation spectra recently recorded in H.Figger's group.As opposite to other experimental setups, it is an electric discharge (and not an optical excitation) that prepares the molecular ion, with the advantage for the theoretical approach, to neglect without lost of accuracy, the otherwise important ionization-dissociation competition. Abel transformation relates the dissociation probability starting from a single ro-vibrational state, to the probability of observing a hydrogen atom at a given pixel of the detector plate. Some statistics on initial ro-vibrational distributions, together with a spatial averaging over laser focus area, lead to photofragments kinetic spectra, with well separated peaks attributed to single vibrational levels. An excellent theory-versus-experiment agreement is reached not only for the kinetic spectra, but also for the angular distributions of fragments originating from two different vibrational levels resulting into more or less alignment. Some characteristic features can be interpreted in terms of basic mechanisms such as bond softening or vibrational trapping.

Attosecond pump-probe transition-state spectroscopy of laser-induced molecular dissociative ionization: Adiabatic versus nonadiabatic dressed-state dynamics

“…with ab initio potentials V 1 (R), V 2 (R) associated respectively to the ground, |1 = | 2 g = |1σ g = |g , and first excited, |2 = | 2 u = |1σ u = |u , electronic states and transition dipole moment μ 12 between them taken from [17]. Figure 1 shows these potentials dressed by 400-nm NIR photons and their deformations due to the field-induced couplings F 0 μ 12 /2 between these dressed potentials.…”

Intense-Laser-Field Ionization of the Hydrogen Molecular IonsH2+andD2+at Cr

“…In an earlier experiment of this kind we have been able, for the first time, to resolve the contributions from different vibrational levels in the energy spectra of the neutral fragments in the dissociation channel [8]. Theoretically predicted novel effects of bond softening, level shifting, and trapping (bond hardening) have been studied state specifically [8] and compared with ab initio simulations starting from the time-dependent Schrödinger equation (TDSE) [10,11].…”

Multiphoton dissociation of HeH+below the He+(1s)+H(1sUrsrey1, Anis2, Esry3 2012Phys. Rev. A214170View full textAdd to dashboardCite

“…Being the simplest molecules, H 2 + and D 2 + have been at the center of many of these studies. Their simplicity allows for theoretical studies with minimal approximations [1,[5][6][7][8][9][10][11], while the accuracy of these calculations opens the possibility for quantitative comparison with experimental results [5,6]. Because of these features, H 2 + and D 2 + serve as benchmark systems, providing insight into how more complicated molecules behave in intense laser fields.…”