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Title: Long-range interactions between polar bialkali ground-state molecules in arbitrary vibrational levels

Abstract

We have calculated the isotropic C{sub 6} coefficients characterizing the long-range van der Waals interaction between two identical heteronuclear alkali-metal diatomic molecules in the same arbitrary vibrational level of their ground electronic state X{sup 1}Σ{sup +}. We consider the ten species made up of {sup 7}Li, {sup 23}Na, {sup 39}K, {sup 87}Rb, and {sup 133}Cs. Following our previous work [Lepers et al., Phys. Rev. A 88, 032709 (2013)], we use the sum-over-state formula inherent to the second-order perturbation theory, composed of the contributions from the transitions within the ground state levels, from the transition between ground-state and excited state levels, and from a crossed term. These calculations involve a combination of experimental and quantum-chemical data for potential energy curves and transition dipole moments. We also investigate the case where the two molecules are in different vibrational levels and we show that the Moelwyn-Hughes approximation is valid provided that it is applied for each of the three contributions to the sum-over-state formula. Our results are particularly relevant in the context of inelastic and reactive collisions between ultracold bialkali molecules in deeply bound or in Feshbach levels.

Authors:
; ; ; ;  [1]
  1. Laboratoire Aimé Cotton, CNRS/Université Paris-Sud/ENS-Cachan, Bât. 505, Campus d’Orsay, 91405 Orsay (France)
Publication Date:
OSTI Identifier:
22415934
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Chemical Physics; Journal Volume: 142; Journal Issue: 21; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
74 ATOMIC AND MOLECULAR PHYSICS; ALKALI METALS; BIMETALS; CESIUM 133; CHEMISTRY; DIPOLE MOMENTS; EXCITED STATES; GROUND STATES; INTERACTION RANGE; LITHIUM 7; MOLECULES; POTASSIUM 39; POTENTIAL ENERGY; RUBIDIUM 87; SODIUM 23; VAN DER WAALS FORCES

Citation Formats

Vexiau, R., Lepers, M., E-mail: maxence.lepers@u-psud.fr, Aymar, M., Bouloufa-Maafa, N., and Dulieu, O.. Long-range interactions between polar bialkali ground-state molecules in arbitrary vibrational levels. United States: N. p., 2015. Web. doi:10.1063/1.4921622.
Vexiau, R., Lepers, M., E-mail: maxence.lepers@u-psud.fr, Aymar, M., Bouloufa-Maafa, N., & Dulieu, O.. Long-range interactions between polar bialkali ground-state molecules in arbitrary vibrational levels. United States. doi:10.1063/1.4921622.
Vexiau, R., Lepers, M., E-mail: maxence.lepers@u-psud.fr, Aymar, M., Bouloufa-Maafa, N., and Dulieu, O.. 2015. "Long-range interactions between polar bialkali ground-state molecules in arbitrary vibrational levels". United States. doi:10.1063/1.4921622.
@article{osti_22415934,
title = {Long-range interactions between polar bialkali ground-state molecules in arbitrary vibrational levels},
author = {Vexiau, R. and Lepers, M., E-mail: maxence.lepers@u-psud.fr and Aymar, M. and Bouloufa-Maafa, N. and Dulieu, O.},
abstractNote = {We have calculated the isotropic C{sub 6} coefficients characterizing the long-range van der Waals interaction between two identical heteronuclear alkali-metal diatomic molecules in the same arbitrary vibrational level of their ground electronic state X{sup 1}Σ{sup +}. We consider the ten species made up of {sup 7}Li, {sup 23}Na, {sup 39}K, {sup 87}Rb, and {sup 133}Cs. Following our previous work [Lepers et al., Phys. Rev. A 88, 032709 (2013)], we use the sum-over-state formula inherent to the second-order perturbation theory, composed of the contributions from the transitions within the ground state levels, from the transition between ground-state and excited state levels, and from a crossed term. These calculations involve a combination of experimental and quantum-chemical data for potential energy curves and transition dipole moments. We also investigate the case where the two molecules are in different vibrational levels and we show that the Moelwyn-Hughes approximation is valid provided that it is applied for each of the three contributions to the sum-over-state formula. Our results are particularly relevant in the context of inelastic and reactive collisions between ultracold bialkali molecules in deeply bound or in Feshbach levels.},
doi = {10.1063/1.4921622},
journal = {Journal of Chemical Physics},
number = 21,
volume = 142,
place = {United States},
year = 2015,
month = 6
}
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