Eur. Phys. J. D 26, 165-171 (2003)
https://doi.org/10.1140/epjd/e2003-00248-8

The short-range reaction matrix in MQDT treatment of dissociative recombination and related processes

¹ Laboratoire de Photophysique Moléculaire, bâtiment 210, Université Paris-Sud, 91405 Orsay, France
² Centre de Physique Atomique Moléculaire et Optique Quantique (CEPAMOQ), Université de Douala, B.P. 24157, Douala, Cameroun
³ Institute for Space Science, P.O. Box MG-36, 76900 Bucharest, Romania
⁴ Foundation of Computer Science Laboratory, University of Aizu, Ikki, Aizuwakamatsu 965-8580, Japan
⁵ Laboratoire de Mécanique, Physique et Géosciences, Université du Havre, 76058 Le Havre, France
⁶ Laboratoire de Chimie Physique, Université Paris VI, Paris, France

Corresponding author: ^a valery.ngassam@ppm.u-psud.fr

Received: 6 January 2003
Revised: 18 April 2003
Published online: 5 August 2003

Abstract

We discuss the Lippmann-Schwinger equation which governs the short-range reaction matrix (K-matrix) in the two-step multichannel quantum defect theory (MQDT) of dissociative recombination and related processes. We show that, if the energy dependence of the electronic coupling between the dissociative state and the ionization continua can be neglected, the convergence of the Born expansion of the Lippmann-Schwinger equation is achieved at second order. For the case of energy-dependent interaction, higher order effects are tested using a non-perturbative method for solving the Lippmann-Schwinger equation. Numerical examples are given for the dissociative recombination and vibrational de-excitation of the H molecular ion.