A simple determination of the potential energy curves and couplings for long-range charge-transfer reactions. Application to the system (ArN 2) +

Abstract

An original method is presented for calculating long-range energies and couplings of the two (non-adiabatic) states A +–B and A–B + of a charge-transfer system (AB) +. This method is applied to the calculation of the charge-exchange cross sections in the system (ArN 2) +. Concerning the reaction from N 2 +, we show that the errors made in approximating the interaction energy and the couplings do not affect strongly the values of the cross sections, that most transitions are well described by the Demkov model, and that the evolution of the cross section is governed by the radius R D (where the coupling is equal to the separation of the states) rather than by the transition probability. We have also obtained qualitative information for the reaction from Ar +.