Theoretical Studies Of Dissociative Recombination Research Articles

Theoretical study of dissociative recombination and vibrational excitation of the ion by an electron impact

Cross-sections for dissociative recombination and electron-impact vibrational excitation of the molecular ion are computed using a theoretical approach that combines the normal modes approximation for the vibrational states of the target ion and use of the UK R-matrix code to evaluate electron–ion scattering matrices for fixed geometries of the ion. Thermally-averaged rate coefficients are obtained from the cross-sections for temperatures in the 10–3000 K range.

Dissociative recombination of BeH+in the interstellar medium

We report a theoretical study of dissociative recombination (DR) of BeH+ by low energy electron impact, using previously computed molecular data as input for a Multichannel Quantum Defect Theory (MQDT) approach. Three electronic symmetries of BeH, 2 Π, 2 Σ+ , and 2 Δ have been included in the calculations. We present cross sections and thermal rate coefficients ready to be used in the modelling of the BeH+ abundance in the interstellar medium and stellar atmosphere.

Theoretical studies of dissociative recombination

In the collision of electrons with molecules and molecular ions, excitation and dissociation are dominated by resonant processes, where the electron becomes temporarily trapped, changing the forces felt by the nuclei. We have carried out calculations on the resonant process leading to dissociative reccombination. We separate the problem into two steps. First, the resonance parameters are obtained from accurate electron scattering calculations using the Complex Kohn variational method. Then these parameters are used as input to the dynamics calculations. We will illustrate the method with the study of dissociative recombination in HF+ CF+ HCO/HCO+ and H2O+.

Excited core states in the dissociative recombination of N+2

Theoretical studies of dissociative recombination along the b′1Σ+u dissociative route of N2 from the v = 0 level of the X2Σ+g ion are described. Rydberg states having both the ground X2Σ+g and A2Πu cores are included in the calculation of cross sections and rate constants. The electronic width connecting these Rydberg series is zero. Nevertheless, the two Rydberg series are connected through the dissociative state. The large electronic width for the A2Πu Rydberg states leads to a factor of 20 decrease in the rate constant at 1000 K electron temperature.