Ultracold Chemistry with Alkali-metal-rare-earth Molecules
Document Type
Article
Publication Date
1-20-2015
Publication Title
Physical Review A
Volume
91
Issue
1
First page number:
12708-1
Last page number:
12708-12
Abstract
A first principles study of the dynamics of Li6(2S)+Li6Yb174(2Σ+)→6Li2(1Σ+) + Yb174(1S) reaction is presented at cold and ultracold temperatures. The computations involve determination and analytic fitting of a three-dimensional potential energy surface for the Li2Yb system and quantum dynamics calculations of varying complexities, ranging from exact quantum dynamics within the close-coupling scheme, to statistical quantum treatment, and universal models. It is demonstrated that the two simplified methods yield zero-temperature limiting reaction rate coefficients in reasonable agreement with the full close-coupling calculations. The effect of the three-body term in the interaction potential is explored by comparing quantum dynamics results from a pairwise potential that neglects the three-body term to that derived from the full interaction potential. Inclusion of the three-body term in the close-coupling calculations was found to reduce the limiting rate coefficients by a factor of two. The reaction exoergicity populates vibrational levels as high as v=19 of the Li62 molecule in the limit of zero collision energy. Product vibrational distributions from the close-coupling calculations reveal sensitivity to inclusion of three-body forces in the interaction potential. Overall, the results indicate that a simplified model based on the long-range potential is able to yield reliable values of the total reaction rate coefficient in the ultracold limit but a more rigorous approach based on statistical quantum or quantum close-coupling methods is desirable when product rovibrational distribution is required.
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File Size
1260 KB
Repository Citation
Makrides, C.,
Hazra, J.,
Pradhan, G. B.,
Petrov, A.,
Kendrick, B. K.,
González-Lezana, T.,
Naduvalath, B.,
Kotochigova, S.
(2015).
Ultracold Chemistry with Alkali-metal-rare-earth Molecules.
Physical Review A, 91(1),
12708-1-12708-12.
http://dx.doi.org/10.1103/PhysRevA.91.012708