Indirect dissociative recombination of LiH$_2^+$ + e$^-$

TL;DR

This paper calculates the indirect dissociative recombination cross sections for LiH₂⁺ + e⁻ using advanced quantum defect theory and rovibrational analysis, revealing a high recombination rate with minimal effects from rovibrational mixing.

Contribution

It introduces a detailed quantum mechanical calculation of the indirect DR process for LiH₂⁺, incorporating exact rovibrational dynamics, which was not previously done for this molecule.

Findings

Calculated a large DR rate of 4.0 x 10⁻⁷ cm³ s⁻¹ at 1 meV

Found that rovibrational mixing has only a small effect on the DR rate

Demonstrated the effectiveness of multichannel quantum defect theory for this system

Abstract

We present the results of calculations determining the cross sections for indirect dissociative recombination of LiH$_2^+$ + $e^-$. These calculations employ multichannel quantum defect theory and Fano's rovibrational frame transformation technique to obtain the indirect DR cross section in the manner described by Ref.\cite{hamilton}. We use \textit{ab initio} electron-molecule scattering codes to calculate quantum defects. In contrast to H$_3^+$, the LiH$_2^+$ molecule exhibits considerable mixing between rotation and vibration; however, by incorporating an exact treatment of the rovibrational dynamics of the LiH$_2^+$, we show that this mixing has only a small effect on the observed DR rate. We calculate a large DR rate for this cation, 4.0 $\times$ 10$^{-7}$ cm$^{3}$ s$^{-1}$ at 1 meV incident electron energy.