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arXiv · 1810.03475

Low temperature scattering with the R-matrix method: the Morse potential

Tom Rivlin·Laura K. McKemmish·Jonathan Tennyson
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Abstract

Experiments are starting to probe collisions and chemical reactions between atoms and molecules at ultra-low temperatures. We have developed a new theoretical procedure for studying these collisions using the R-matrix method. Here this method is tested for the atom -- atom collisions described by a Morse potential. Analytic solutions for continuum states of the Morse potential are derived and compared with numerical results computed using an R-matrix method where the inner region wavefunctions are obtained using a standard nuclear motion algorithm. Results are given for eigenphases and scattering lengths. Excellent agreement is obtained in all cases. Progress in developing a general procedure for treating ultra-low energy reactive and non-reactive collisions is discussed.

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Tom Rivlin, Laura K. McKemmish, Jonathan Tennyson. 2018-10-08. Low temperature scattering with the R-matrix method: the Morse potential. https://arxiv.org/abs/1810.03475

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