THEORETICAL-STUDY OF MULTIELECTRON DISSOCIATIVE IONIZATION OF DIATOMIC-MOLECULES AND CLUSTERS IN A STRONG LASER FIELD

The analysis of electron potentials in multicharged molecules and smal l clusters allows one to determine which of these systems may be ioniz ed in a strong laser field by the quasiresonance mechanism. The presen ce of moderately transparent interionic potential barriers (for electr on tunneling) is necessary for the quasiresonance electron energy enha ncement and, consequently, for ionization [Zuo and Bandrauk, Phys. Rev . A 52, R2511 (1995)]. In multicharged systems, which spatially expand by Coulomb explosion, the interionic barriers increase with time. The simulation of electron motion in such systems demonstrates the presen ce of a different kind of charge resonance enhanced ionization mechani sm whose efficiency depends on the dynamics of the increase of the int erionic barriers. This dynamic charge resonance enhanced ionization me chanism is of classical origin and its efficiency is higher than that of the static (frozen geometry) mechanism. [S1050-2947(98)06410-5].