PHOTODISSOCIATION OF AR-2(+) IN STRONG LASER FIELDS

We present extensive calculations for the dissociation of Ar-2(+) caus ed by the interaction with strong (I(peak)less than or similar to 10(4 ) W/cm(2)) and short (T <5 ps) laser pulses; the calculations are stim ulated by the recent experimental study of Wunderlich et al. [Chem. Ph ys. Lett. 256 (1996) 43]. The time-dependent Schrodinger equation is s olved exactly within a two-state model including the binding ground st ate, A(2) Sigma(u)(+), and the repulsive excited state, D-2 Sigma(g)(). In order to get a most complete picture of the dissociation process the intensity and the frequency of the laser pulse as well as the ini tial vibrational state of Ar-2(+) are varied over large ranges. It is observed that the reflection principle, known from spectroscopy with l ong and weak light sources, governs -at least qualitatively -the disso ciation dynamics up to relatively high intensities. Special strong-fie ld effects such as stabilization occur, if at all, at very high intens ities; in general, however, they are rather insignificant for the inte nsity range probed in the experiment. (C) 1997 Elsevier Science B.V.