Longrange interactions between polar bialkali groundstate molecules in arbitrary vibrational levels
Abstract
We have calculated the isotropic C{sub 6} coefficients characterizing the longrange van der Waals interaction between two identical heteronuclear alkalimetal 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 sumoverstate formula inherent to the secondorder perturbation theory, composed of the contributions from the transitions within the ground state levels, from the transition between groundstate and excited state levels, and from a crossed term. These calculations involve a combination of experimental and quantumchemical 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 MoelwynHughes approximation is valid provided that it is applied for each of the three contributions to the sumoverstate 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:
 Laboratoire Aimé Cotton, CNRS/Université ParisSud/ENSCachan, 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., Email: maxence.lepers@upsud.fr, Aymar, M., BouloufaMaafa, N., and Dulieu, O.. Longrange interactions between polar bialkali groundstate molecules in arbitrary vibrational levels. United States: N. p., 2015.
Web. doi:10.1063/1.4921622.
Vexiau, R., Lepers, M., Email: maxence.lepers@upsud.fr, Aymar, M., BouloufaMaafa, N., & Dulieu, O.. Longrange interactions between polar bialkali groundstate molecules in arbitrary vibrational levels. United States. doi:10.1063/1.4921622.
Vexiau, R., Lepers, M., Email: maxence.lepers@upsud.fr, Aymar, M., BouloufaMaafa, N., and Dulieu, O.. 2015.
"Longrange interactions between polar bialkali groundstate molecules in arbitrary vibrational levels". United States.
doi:10.1063/1.4921622.
@article{osti_22415934,
title = {Longrange interactions between polar bialkali groundstate molecules in arbitrary vibrational levels},
author = {Vexiau, R. and Lepers, M., Email: maxence.lepers@upsud.fr and Aymar, M. and BouloufaMaafa, N. and Dulieu, O.},
abstractNote = {We have calculated the isotropic C{sub 6} coefficients characterizing the longrange van der Waals interaction between two identical heteronuclear alkalimetal 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 sumoverstate formula inherent to the secondorder perturbation theory, composed of the contributions from the transitions within the ground state levels, from the transition between groundstate and excited state levels, and from a crossed term. These calculations involve a combination of experimental and quantumchemical 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 MoelwynHughes approximation is valid provided that it is applied for each of the three contributions to the sumoverstate 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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