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arXiv · 1202.4531

Total angular momentum representation for atom-molecule collisions in electric fields

T. V. Tscherbul
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Abstract

It is shown that the atom-molecule collision problem in the presence of an external electric field can be solved using the total angular momentum representation in the body-fixed coordinated frame, leading to a computationally efficient method for ab initio modeling of low-temperature scattering phenomena. Our calculations demonstrate rapid convergence of the cross sections for vibrational and Stark relaxation in He-CaD collisions with the number of total angular momentum states in the basis set, leading to a 5-100 fold increase in computational efficiency over the previously used methods based on the fully uncoupled space-fixed representation. These results open up the possibility of carrying out numerically converged quantum scattering calculations on a wide array of atom-molecule collisions and chemical reactions in the presence of electric fields.

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T. V. Tscherbul. 2012-02-21. Total angular momentum representation for atom-molecule collisions in electric fields. https://doi.org/10.1103/physreva.85.052710

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