QUANTUM INTERFERENCES OF SUPER-EXCITED STATES: APPLICATION TO ELECTRON-MOLECULAR CATION REACTIVE COLLISIONS

The theoretical description of different reactive collisions - dissociative recombination, dissociative excitation, elastic, inelastic and super-elastic collisions - of electrons with molecular cations is illustrated in terms of a method (1) based on the Multichannel Quantum Defect Theory (2-4). We outline the various aspects of this approach - representations of molecular states (many of them, electronically or ro-vibrationally super-excited), channel interactions, mechanisms and competitive processes. The multi-channel character of the collisions, implying quantum interferences between zero-order states of the molecular system, is emphasized. We support these aspects with examples and applications on various diatomic molecular cations - 2 , H + HD+, DT+, HeH+, and NO+ - with electrons of energy between 0.01 meV and 13 eV. The computed cross sections and rate coefficients aim at providing input data for the kinetic modelling of ionized media of astrophysical, planetary, environmental and energetic interest.