Improved Recursive Computation of Clebsch-Gordan Coefficients

Guanglang Xu

doi:10.1016/j.jqsrt.2020.107210

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arXiv · 2006.04267

Improved Recursive Computation of Clebsch-Gordan Coefficients

Guanglang Xu

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Abstract

Fast, accurate, and stable computation of the Clebsch-Gordan (C-G) coefficients is always desirable, for example, in light scattering simulations, the translation of the multipole fields, quantum physics and chemistry. Current recursive methods for computing the C-G coefficients are often unstable for large quantum numbers due to numerical overflow or underflow. In this paper, we present an improved method, the so-called sign-exponent recurrence, for the recursive computation of C-G coefficients. The result shows that the proposed method can significantly improve the stability of the computation without losing its efficiency, producing accurate values for the C-G coefficients even with very large quantum numbers.

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BibTeX RIS

Guanglang Xu. 2020-06-07. Improved Recursive Computation of Clebsch-Gordan Coefficients. https://doi.org/10.1016/j.jqsrt.2020.107210

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