On the feasibility of reconstructing the MQD theory parameters from high-resolution optical spectra

Dissociative recombination (DR) of slow electrons and molecular ions is des cribed within the MQD theory by a set of parameters deduced from the adiaba tic characteristics of highly excited molecules. In this work we attract at tention to the fact that under near-threshold conditions, negligibly small variations of some of these parameters (e.g., dependence of quantum defects on The interatomic distance) can entail significant changes in the cross s ections and rate constants for DR reactions. Therefore we propose a special program for reconstructing parameters of the MQD theory from spectra of tw o-photon (1 + 1)-ionization of molecules induced by a weak field prepopulat ing an intermediate (working) level and by a strong monochromatic linearly polarized radiation. The form of the photoelectron spectra is analyzed as a function of variations of the parameters introduced in the theory and spec tral ranges where these parameters can be assessed unambiguously and with a good accuracy are indicated.