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arXiv · 2008.12936

Discrete Variable Representation method in the study of few-body quantum systems with non-zero angular momentum

V. A. Timoshenko·E. A. Yarevsky
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Abstract

The systems with small binding energies and widely distributed in space bound-state wave functions are considered. Because the interaction potential is weak and rather localized compared to the characteristic sizes of wave functions of these systems, the problem of an accurate determination of binding energy and wave functions is complicated. An essential part of the study is the development and application of the discrete-variable representation (DVR) method. This method is based on the determination of basis functions and the nodes and weights of a quadrature formula in such way that the values of a function are zero at all these nodes but one. With this representation the time required for calculating the Hamiltonian matrix elements is substantially reduced. The binding energies of several systems consisting of helium and lithium atoms have been obtained using the DVR method.

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V. A. Timoshenko, E. A. Yarevsky. 2020-08-29. Discrete Variable Representation method in the study of few-body quantum systems with non-zero angular momentum. https://doi.org/10.3103/s1062873821050221

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