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arXiv · 2603.17923

Rotational excitation of asymmetric-top molecular ions by electron impact: application to H$_2$O$^+$, HDO$^+$, and D$_2$O$^+$

Joshua Forer
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Abstract

The rotational excitation of the three asymmetric-top molecular ion isotopologues H$_2$O$^+$, HDO$^+$, and D$_2$O$^+$ is studied theoretically using a combined framework of electron-molecule R-matrix scattering theory, multichannel quantum-defect theory, frame transformation theory, and the Coulomb-Born approximation. The latter two have been adapted here for asymmetric-top rotors. State-resolved cross sections and kinetic rate coefficients for transitions from the rotational ground state of the ions are presented. State-resolved rate coefficients for all calculated transitions $N=0\ldotstwo4$ are included as supplementary material and will be made available through the EMAA database.

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Joshua Forer. 2026-03-18. Rotational excitation of asymmetric-top molecular ions by electron impact: application to H$_2$O$^+$, HDO$^+$, and D$_2$O$^+$. https://arxiv.org/abs/2603.17923

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