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Title: Inelastic low-energy collisions of electrons with HeH +: Rovibrational excitation and dissociative recombination

Inelastic low-energy (0–1 eV) collisions of electrons with HeH + cations are treated theoretically, with a focus on the rovibrational excitation and dissociative recombination (DR) channels. In an application of ab initio multichannel quantum defect theory, the description of both processes is based on the Born-Oppenheimer quantum defects. The quantum defects were determined using the R-matrix approach in two different frames of reference: the center-of-charge and the center-of-mass frames. The results obtained in the two reference systems, after implementing the Fano-Jungen style rovibrational frame-transformation technique, show differences in the rate of convergence for these two different frames of reference. We find good agreement with the available theoretically predicted rotationally inelastic thermal rate coefficients. Our computed DR rate also agrees well with the available experimental results. Moreover, several computational experiments shed light on the role of rotational and vibrational excitations in the indirect DR mechanism that governs the low energy HeH + dissociation process. While the rotational excitation is several orders of magnitude more probable process at the studied collision energies, the closed-channel resonances described by the high- n, rotationally excited neutral molecules of HeH contribute very little to the dissociation probability. However, the situation is very different for resonances definedmore » by the high- n, vibrationally excited HeH molecules, which are found to dissociate with approximately 90% probability.« less
Authors:
 [1] ;  [2]
  1. Academy of Sciences of the Czech Republic (ASCR), Prague (Czech Republic). J. Heyrovsky Inst. of Physical Chemistry
  2. Purdue Univ., West Lafayette, IN (United States). Dept. of Physics and Astronomy
Publication Date:
Grant/Contract Number:
SC0010545; LD14088; CM1301
Type:
Accepted Manuscript
Journal Name:
Journal of Chemical Physics
Additional Journal Information:
Journal Volume: 147; Journal Issue: 5; Journal ID: ISSN 0021-9606
Publisher:
American Institute of Physics (AIP)
Research Org:
Purdue Univ., West Lafayette, IN (United States)
Sponsoring Org:
USDOE Office of Science (SC); European Union (EU); Ministry of Education, Youth and Sports (MSMT) (Czech Republic)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; 74 ATOMIC AND MOLECULAR PHYSICS; gemstones; rotational spectra; recombination reactions; atomic and molecular collisions; Rydberg spectroscopy; resonant states; vibrational spectra; collision energies; multichannel quantum defect; scattering matrix
OSTI Identifier:
1474040
Alternate Identifier(s):
OSTI ID: 1373985

Čurík, Roman, and Greene, Chris H. Inelastic low-energy collisions of electrons with HeH+: Rovibrational excitation and dissociative recombination. United States: N. p., Web. doi:10.1063/1.4994921.
Čurík, Roman, & Greene, Chris H. Inelastic low-energy collisions of electrons with HeH+: Rovibrational excitation and dissociative recombination. United States. doi:10.1063/1.4994921.
Čurík, Roman, and Greene, Chris H. 2017. "Inelastic low-energy collisions of electrons with HeH+: Rovibrational excitation and dissociative recombination". United States. doi:10.1063/1.4994921. https://www.osti.gov/servlets/purl/1474040.
@article{osti_1474040,
title = {Inelastic low-energy collisions of electrons with HeH+: Rovibrational excitation and dissociative recombination},
author = {Čurík, Roman and Greene, Chris H.},
abstractNote = {Inelastic low-energy (0–1 eV) collisions of electrons with HeH+ cations are treated theoretically, with a focus on the rovibrational excitation and dissociative recombination (DR) channels. In an application of ab initio multichannel quantum defect theory, the description of both processes is based on the Born-Oppenheimer quantum defects. The quantum defects were determined using the R-matrix approach in two different frames of reference: the center-of-charge and the center-of-mass frames. The results obtained in the two reference systems, after implementing the Fano-Jungen style rovibrational frame-transformation technique, show differences in the rate of convergence for these two different frames of reference. We find good agreement with the available theoretically predicted rotationally inelastic thermal rate coefficients. Our computed DR rate also agrees well with the available experimental results. Moreover, several computational experiments shed light on the role of rotational and vibrational excitations in the indirect DR mechanism that governs the low energy HeH+ dissociation process. While the rotational excitation is several orders of magnitude more probable process at the studied collision energies, the closed-channel resonances described by the high-n, rotationally excited neutral molecules of HeH contribute very little to the dissociation probability. However, the situation is very different for resonances defined by the high-n, vibrationally excited HeH molecules, which are found to dissociate with approximately 90% probability.},
doi = {10.1063/1.4994921},
journal = {Journal of Chemical Physics},
number = 5,
volume = 147,
place = {United States},
year = {2017},
month = {8}
}