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 small clusters allows one to determine which of these systems may be ionized in a strong laser field by the quasiresonance mechanism. The presence of moderately transparent interionic potential barriers (for electron tunneling) is necessary for the quasiresonance electron energy enhancement 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 presence of a different kind of charge resonance enhanced ionization mechanism whose efficiency depends on the dynamics of the increase of the interionic barriers. This dynamic charge resonance enhanced ionization mechanism is of classical origin and its efficiency is higher than that of the static (frozen geometry) mechanism.