Dissociative recombination of H3+ in the ground and excited vibrational states

TL;DR

This paper improves theoretical calculations of H3+ dissociative recombination rates by including more vibrational and rotational states, leading to better agreement with experiments and insights into state-specific behaviors.

Contribution

It introduces more accurate vibrational wave functions and a larger rotational state set in DR rate calculations, enhancing agreement with experimental data and revealing the significance of excited states.

Findings

Better agreement with experimental DR rates.

Significant differences between ortho- and para-H3+ at low energies.

Vibrationally excited states show higher DR rates.

Abstract

The article presents calculated dissociative recombination (DR) rate coefficients for H+3 . The previous theoretical work on H+3 was performed using the adiabatic hyperspherical approximation to calculate the target ion vibrational states and it considered just a limited number of ionic rotational states. In this study, we use accurate vibrational wave functions and a larger number of possible rotational states of the H3+ ground vibrational level. The DR rate coefficient obtained is found to agree better with the experimental data from storage-ring experiments than the previous theoretical calculation. We present evidence that excited rotational states could be playing an important role in those experiments for collision energies above 10 meV. The DR rate coefficients calculated separately for ortho- and para-H3+ are predicted to differ significantly at low energy, a result consistent with a recent experiment. We also present DR rate coefficients for vibrationally-excited initial states of H3+, which are found to be somewhat larger than the rate coefficient for the ground vibrational level.