J. Phys. II France
Volume 1, Numéro 9, September 1991
Page(s) 1033 - 1051
DOI: 10.1051/jp2:1991204
J. Phys. II France 1 (1991) 1033-1051

Above threshold photodissociation in H 2 and H 2+

A. D. Bandrauk, E. Constant and J.-M. Gauthier

Département de chimie, Faculté des sciences, Université de Sherbrooke, Sherbrooke, Québec, J1K 2R1, Canada

(Received 12 March 1991, accepted in final form 27 May 1991)

A coupled equations approach is used to calculate the probabilities of photophysical processes in the ten photon absorption spectrum of H 2 at wavelength $\lambda = 532$ nm. At high intensities, i.e., I > 1010 W/cm 2, it is shown that above threshold photodissociation (ATPD) occurs readily in the B $^1\Sigma^+_{\rm u}$ state of H 2 and in X  $^2 \Sigma_{\rm g}^+$ of H +2. Laser-induced avoided crossings between the dressed B and F electronic potentials of H 2 and also between the dressed X and A potentials of H +2 result in anomalous proton yields at intensities above 10 11 W/cm 2. The vibronic structure of the dressed X  $^2\Sigma^+_{\rm g}$ potential of H +2 appears in all photodissociation yields as laser-induced resonances with intensity dependent line widths.

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