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

Bulletin of the American Physical Society

Cold and ultracold H$_2$-H$_2$ collisions on high accuracy ab initio potentials

N. Balakrishnan, Samantha Fonseca dos Santos, Robert C. Forrey, P.C. Stancil, Piotr Jankowski, K. Szalewicz

Published Jun 5, 2012• 0 citations
OpenAlex

Related papers

Quantum calculations of H$_2$--H$_2$ collisions: from ultracold to thermal energies

Goulven Quéméner, Roman V. Krems, N. Balakrishnan

Bulletin of the American Physical Society•May 23, 2009•0 citations

Cold and ultracold NH–NH collisions: The field-free case

Liesbeth M. C. Janssen, Piotr Szymon Żuchowski, Ad van der Avoird +2 more

We present elastic and inelastic spin-changing cross sections for cold and ultracold NH(X (3)Σ(-)) + NH(X (3)Σ(-)) collisions, obtained from full quantum scattering calculations on an accurate ab initio quintet potential-energy surface. Although we consider only collisions in zero field, we focus on the cross sections relevant for magnetic trapping experiments. It is shown that evaporative cooling of both fermionic (14)NH and bosonic (15)NH is likely to be successful for hyperfine states that allow s-wave collisions. The calculated cross sections are very sensitive to the details of the interaction potential, due to the presence of (quasi)bound state resonances. The remaining inaccuracy of the ab initio potential-energy surface therefore gives rise to an uncertainty in the numerical cross-section values. However, based on a sampling of the uncertainty range of the ab initio calculations, we conclude that the exact potential is likely to be such that the elastic-to-inelastic cross-section ratio is sufficiently large to achieve efficient evaporative cooling. This likelihood is only weakly dependent on the size of the channel basis set used in the scattering calculations.

arXiv:1012.0804•The Journal of Chemical Physics•Mar 28, 2011•25 citations

The effect of energy and angular momentum gaps in cold and ultracold collisions of H$_2$ molecules

Samantha Fonseca dos Santos, N. Balakrishnan, S. Lepp +3 more

Bulletin of the American Physical Society•Jun 15, 2011•0 citations

Photoinitiated collisions between cold Cs Rydberg atoms

K. Richard Overstreet, Arne Schwettmann, Jonathan Tallant +1 more

Experimental studies of a photoinitiated collision in an ultracold Cs Rydberg gas are presented. The process is characterized by measuring the laser intensity dependence of the absorption, the number of particles leaving each collision, and the recoil velocity of the collision fragments. The results of the experiment are compared to ab initio Rydberg pair interaction potentials.

Physical Review A•Jul 27, 2007•47 citations

Cold collisions between atoms and diatomic molecules

Marius Lysebo, Leif Veseth

Collision cross sections are calculated for the three systems ${\text{O}}_{2}\text{-He}$, ${\text{Na}}_{2}\text{-Na}$ and ${\text{K}}_{2}\text{-K}$ at cold and ultracold temperatures. We discuss their relevance for cold molecule formation by buffer-gas cooling and by other cooling methods where collisions between molecules and atoms are important, e.g photoassociation. The molecule is treated as a rigid rotator in the electronic and vibrational ground state. We have calculated ab initio the potential energy surfaces for the three systems with special emphasis on the long range potential which is very important at low energies. With relevance to buffer gas cooling, we have also studied the thermalization process between ${\text{O}}_{2}$ molecules and He atoms as determined by the calculated cross sections.

Physical Review A•Mar 24, 2008•15 citations

Ultra-cold electron collisions with the N$_2$H radical

Brendan M. McLaughlin, Robert C. Forrey

Bulletin of the American Physical Society•May 21, 2009•0 citations
Cold and ultracold H2_22​-H2_22​ collisions on high accuracy ab initio potentials
Quantum calculations of H2_22​--H2_22​ collisions: from ultracold to thermal energies
We present elastic and inelastic spin-changing cross sections for cold and ultracold NH(X (3)Σ(-)) + NH(X (3)Σ(-)) collisions, obtained from full quantum scattering calculations on an accurate ab initio quintet potential-energy surface. Although we consider only collisions in zero field, we focus on the cross sections relevant for magnetic trapping experiments. It is shown that evaporative cooling of both fermionic (14)NH and bosonic (15)NH is likely to be successful for hyperfine states that allow s-wave collisions. The calculated cross sections are very sensitive to the details of the interaction potential, due to the presence of (quasi)bound state resonances. The remaining inaccuracy of the ab initio potential-energy surface therefore gives rise to an uncertainty in the numerical cross-section values. However, based on a sampling of the uncertainty range of the ab initio calculations, we conclude that the exact potential is likely to be such that the elastic-to-inelastic cross-section ratio is sufficiently large to achieve efficient evaporative cooling. This likelihood is only weakly dependent on the size of the channel basis set used in the scattering calculations.
The effect of energy and angular momentum gaps in cold and ultracold collisions of H2_22​ molecules
Collision cross sections are calculated for the three systems O2-He{\text{O}}_{2}\text{-He}O2​-He, Na2-Na{\text{Na}}_{2}\text{-Na}Na2​-Na and K2-K{\text{K}}_{2}\text{-K}K2​-K at cold and ultracold temperatures. We discuss their relevance for cold molecule formation by buffer-gas cooling and by other cooling methods where collisions between molecules and atoms are important, e.g photoassociation. The molecule is treated as a rigid rotator in the electronic and vibrational ground state. We have calculated ab initio the potential energy surfaces for the three systems with special emphasis on the long range potential which is very important at low energies. With relevance to buffer gas cooling, we have also studied the thermalization process between O2{\text{O}}_{2}O2​ molecules and He atoms as determined by the calculated cross sections.
Ultra-cold electron collisions with the N2_22​H radical