Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Physical Review A

Low-Energy Inelastic Scattering of He(2 S3) on He(1 S1)

R. E. Olson, Reinhard Morgenstern, D. C. Lorents, James C. Browne, L. Lenamon

Published Nov 1, 1973• 11 citations
Publisher

Abstract

Time-of-flight scattering measurements at 8.65 eV (c.m.) display strong inelastic scattering from $\mathrm{He}(2 ^{3}S)+\mathrm{He}(1 ^{1}S)$ to $\mathrm{He}(2 ^{3}P)+\mathrm{He}(1 ^{1}S)$. Close-coupled quantum-mechanical calculations employing ab initio potential curves and matrix elements show the inelastic process is due to strong rotational coupling between the $c ^{3}\ensuremath{\Sigma}_{g}^{+}$ state of $\mathrm{He}(2 ^{3}S)+\mathrm{He}(1 ^{1}S)$ and the $b ^{3}\ensuremath{\Pi}_{g}$ state of $\mathrm{He}(2 ^{3}P)+\mathrm{He}(1 ^{1}S)$. Good agreement is found between the calculated and the experimentally measured inelastic-scattering cross sections.

DOI
10.1103/physreva.8.2387

Related papers

Theoretical low-energy inelastic-scattering cross sections for He(2 $sup 3$S) + He(1 $sup 1$S) $Yields$ He(2 $sup 3$P) + He(1 $sup 1$S): curve crossing between the c $sup 3$$Sigma$$sup +$/subg/ and b $sup 3$PI/subg/ states of He$sub 2$

L. Lenamon, John C. Browne, R.E. Olson

Physical Review A•Nov 1, 1973•0 citations

Low-temperature collisions of Na2 with He

Wang Yue, Dong De-Zhi, Weiyan Li +3 more

The close coupling calculation of rotationally inelastic collision of He with Na2 is first performed by employing a recently computed ab initio potential energy surface. The process of rovibrational energy excitation and relaxation of Na2 in collision with He has been studied in detail based on the single and double exitations coupled cluster with a noniterative perturbation treatment of triple excitations CCSD （T） potential energy surface. Our results are in good agreement with the experimental results. Our results show that: （1）The elastic cross section（Δj=0） is much larger than the inelastic cross section. （2）The largest amplitude occurs at small scattering angles. At low Δj transition, the He projectile is predominantly forward scattering. Backward scattering occurs as Δj increases. （3）For inelastic cross section, the most effective transition is that with Δj=2.（4）The fast narrow diffraction oscillations in the cross sections are the obvious characteristics for the low Δj inelastic transitions, which decreases with increasing j. （5）The elastic differential-cross-sections（DCS）provides a useful visualization of rotational rainbows at low translational energy. It is beneficial to reducing the loss in molecular cooling and trapping.

Acta Physica Sinica•Jan 1, 2009•1 citation

Scattering of NH3 and ND3 with rare gas atoms at low collision energy

Jérôme Loreau, Ad van der Avoird

We present a theoretical study of elastic and rotationally inelastic collisions of NH3 and ND3 with rare gas atoms (He, Ne, Ar, Kr, Xe) at low energy. Quantum close-coupling calculations have been performed for energies between 0.001 and 300 cm(-1). We focus on collisions in which NH3 is initially in the upper state of the inversion doublet with j = 1, k = 1, which is the most relevant in an experimental context as it can be trapped electrostatically and Stark-decelerated. We discuss the presence of resonances in the elastic and inelastic cross sections, as well as the trends in the inelastic cross sections along the rare gas series and the differences between NH3 and ND3 as a colliding partner. We also demonstrate the importance of explicitly taking into account the umbrella (inversion) motion of NH3 in order to obtain accurate scattering cross sections at low collision energy. Finally, we investigate the possibility of sympathetic cooling of ammonia using cold or ultracold rare gas atoms. We show that some systems exhibit a large ratio of elastic to inelastic cross sections in the cold regime, which is promising for sympathetic cooling experiments. The close-coupling calculations are based on previously reported ab initio potential energy surfaces for NH3-He and NH3-Ar, as well as on new, four-dimensional, potential energy surfaces for the interaction of ammonia with Ne, Kr, and Xe, which were computed using the coupled-cluster method and large basis sets. We compare the properties of the potential energy surfaces corresponding to the interaction of ammonia with the various rare gas atoms.

The Journal of Chemical Physics•Nov 11, 2015•31 citations

Theoretical low-energy scattering cross sections for He(2$sup 1$S) + He(1$sup 1$S) in equilibrium He(2$sup 1$P) + He(1$sup 1$S)

Edward J. Shipsey, John C. Browne, R. E. Olson

Physical Review A•Apr 1, 1975•0 citations

Long-range interactions for He(nS)–He(n′S) and He(nS)–He(n′P)

Junlang Zhang, Z.-C. Yan, D. Vrinceanu +2 more

For helium, long-range interaction coefficients ${C}_{3}$, ${C}_{6}$, ${C}_{8}$, ${C}_{9}$, and ${C}_{10}$ for all $S\text{\ensuremath{-}}S$ and $S\text{\ensuremath{-}}P$ pairs of the energetically lowest five states $(1\phantom{\rule{0.2em}{0ex}}^{1}S,\phantom{\rule{0.2em}{0ex}}2\phantom{\rule{0.2em}{0ex}}^{3}S,\phantom{\rule{0.2em}{0ex}}2\phantom{\rule{0.2em}{0ex}}^{1}S,\phantom{\rule{0.2em}{0ex}}2\phantom{\rule{0.2em}{0ex}}^{3}P,$ and $2\phantom{\rule{0.2em}{0ex}}^{1}P)$ are calculated precisely using correlated wave functions in Hylleraas coordinates. Finite nuclear isotope mass effects are included.

arXiv:physics/0603232•Physical Review A•Jul 26, 2006•33 citations

Probing Scattering Resonances in (Ultra)Cold Inelastic NO–He Collisions

Jolijn Onvlee, Ad van der Avoird, Gerrit C. Groenenboom +1 more

We theoretically study inelastic collisions between NO radicals and He atoms at low collision energies, focusing on the occurrence of scattering resonances. We specifically investigate de-excitation of rotationally excited NO radicals (X (2)Π1/2, v = 0, j = 3/2, f) at collision energies ranging from 10(-3) to 20 cm(-1) and compute integral and differential cross sections using quantum mechanical close-coupling calculations. Although unconventional, we show that the measurement of rotational de-excitation cross sections brings several advantages to experiments that aim to study rotational energy transfer at temperatures approaching zero kelvin. We analyze the nature and partial wave composition of the quasi-bound states associated with each individual resonance and compute the scattering wave functions. The differential cross sections contain the partial wave fingerprints of the scattering process and are found to change drastically as the collision energy is varied over the resonances. The prospects for measuring these differential cross sections in inelastic de-excitation collisions at low energies are discussed.

The Journal of Physical Chemistry A•Jan 13, 2016•12 citations
Time-of-flight scattering measurements at 8.65 eV (c.m.) display strong inelastic scattering from He(23S)+He(11S)\mathrm{He}(2 ^{3}S)+\mathrm{He}(1 ^{1}S)He(23S)+He(11S) to He(23P)+He(11S)\mathrm{He}(2 ^{3}P)+\mathrm{He}(1 ^{1}S)He(23P)+He(11S). Close-coupled quantum-mechanical calculations employing ab initio potential curves and matrix elements show the inelastic process is due to strong rotational coupling between the c3\ensuremathΣg+c ^{3}\ensuremath{\Sigma}_{g}^{+}c3\ensuremathΣg+​ state of He(23S)+He(11S)\mathrm{He}(2 ^{3}S)+\mathrm{He}(1 ^{1}S)He(23S)+He(11S) and the b3\ensuremathΠgb ^{3}\ensuremath{\Pi}_{g}b3\ensuremathΠg​ state of He(23P)+He(11S)\mathrm{He}(2 ^{3}P)+\mathrm{He}(1 ^{1}S)He(23P)+He(11S). Good agreement is found between the calculated and the experimentally measured inelastic-scattering cross sections.
Theoretical low-energy inelastic-scattering cross sections for He(2 sup3sup 3sup3S) + He(1 sup1sup 1sup1S) YieldsYieldsYields He(2 sup3sup 3sup3P) + He(1 sup1sup 1sup1S): curve crossing between the c sup3sup 3sup3SigmaSigmaSigmasup+sup +sup+/subg/ and b sup3sup 3sup3PI/subg/ states of Hesub2sub 2sub2
The close coupling calculation of rotationally inelastic collision of He with Na2 is first performed by employing a recently computed ab initio potential energy surface. The process of rovibrational energy excitation and relaxation of Na2 in collision with He has been studied in detail based on the single and double exitations coupled cluster with a noniterative perturbation treatment of triple excitations CCSD （T） potential energy surface. Our results are in good agreement with the experimental results. Our results show that: （1）The elastic cross section（Δj=0） is much larger than the inelastic cross section. （2）The largest amplitude occurs at small scattering angles. At low Δj transition, the He projectile is predominantly forward scattering. Backward scattering occurs as Δj increases. （3）For inelastic cross section, the most effective transition is that with Δj=2.（4）The fast narrow diffraction oscillations in the cross sections are the obvious characteristics for the low Δj inelastic transitions, which decreases with increasing j. （5）The elastic differential-cross-sections（DCS）provides a useful visualization of rotational rainbows at low translational energy. It is beneficial to reducing the loss in molecular cooling and trapping.
We present a theoretical study of elastic and rotationally inelastic collisions of NH3 and ND3 with rare gas atoms (He, Ne, Ar, Kr, Xe) at low energy. Quantum close-coupling calculations have been performed for energies between 0.001 and 300 cm(-1). We focus on collisions in which NH3 is initially in the upper state of the inversion doublet with j = 1, k = 1, which is the most relevant in an experimental context as it can be trapped electrostatically and Stark-decelerated. We discuss the presence of resonances in the elastic and inelastic cross sections, as well as the trends in the inelastic cross sections along the rare gas series and the differences between NH3 and ND3 as a colliding partner. We also demonstrate the importance of explicitly taking into account the umbrella (inversion) motion of NH3 in order to obtain accurate scattering cross sections at low collision energy. Finally, we investigate the possibility of sympathetic cooling of ammonia using cold or ultracold rare gas atoms. We show that some systems exhibit a large ratio of elastic to inelastic cross sections in the cold regime, which is promising for sympathetic cooling experiments. The close-coupling calculations are based on previously reported ab initio potential energy surfaces for NH3-He and NH3-Ar, as well as on new, four-dimensional, potential energy surfaces for the interaction of ammonia with Ne, Kr, and Xe, which were computed using the coupled-cluster method and large basis sets. We compare the properties of the potential energy surfaces corresponding to the interaction of ammonia with the various rare gas atoms.
Theoretical low-energy scattering cross sections for He(2sup1sup 1sup1S) + He(1sup1sup 1sup1S) in equilibrium He(2sup1sup 1sup1P) + He(1sup1sup 1sup1S)
For helium, long-range interaction coefficients C3{C}_{3}C3​, C6{C}_{6}C6​, C8{C}_{8}C8​, C9{C}_{9}C9​, and C10{C}_{10}C10​ for all $S\text{\ensuremath{-}}S$ and $S\text{\ensuremath{-}}P$ pairs of the energetically lowest five states (11S,23S,21S,23P,(1\phantom{\rule{0.2em}{0ex}}^{1}S,\phantom{\rule{0.2em}{0ex}}2\phantom{\rule{0.2em}{0ex}}^{3}S,\phantom{\rule{0.2em}{0ex}}2\phantom{\rule{0.2em}{0ex}}^{1}S,\phantom{\rule{0.2em}{0ex}}2\phantom{\rule{0.2em}{0ex}}^{3}P,(11S,23S,21S,23P, and 21P)2\phantom{\rule{0.2em}{0ex}}^{1}P)21P) are calculated precisely using correlated wave functions in Hylleraas coordinates. Finite nuclear isotope mass effects are included.
We theoretically study inelastic collisions between NO radicals and He atoms at low collision energies, focusing on the occurrence of scattering resonances. We specifically investigate de-excitation of rotationally excited NO radicals (X (2)Π1/2, v = 0, j = 3/2, f) at collision energies ranging from 10(-3) to 20 cm(-1) and compute integral and differential cross sections using quantum mechanical close-coupling calculations. Although unconventional, we show that the measurement of rotational de-excitation cross sections brings several advantages to experiments that aim to study rotational energy transfer at temperatures approaching zero kelvin. We analyze the nature and partial wave composition of the quasi-bound states associated with each individual resonance and compute the scattering wave functions. The differential cross sections contain the partial wave fingerprints of the scattering process and are found to change drastically as the collision energy is varied over the resonances. The prospects for measuring these differential cross sections in inelastic de-excitation collisions at low energies are discussed.