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arXiv · 2003.14197

Expression of relativistic expectation values of powers of $r$ in terms of Clebsch-Gordan coefficients

Jean-Christophe Pain
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Abstract

It is shown that, in the relativistic hydrogenic approximation, expectation values of the type $\langle n\ell j|r^k|n\ell j\rangle$ can be expressed in terms of Clebsch-Gordan coefficients or $3jm$ symbols. This generalizes the results obtained by Varshalovich and Karpova [Opt. Spectrosc. 118, 1-5 (2015); Opt. Spektrosk. 118, 3-7] in the non-relativistic hydrogenic case.

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Jean-Christophe Pain. 2020-03-31. Expression of relativistic expectation values of powers of $r$ in terms of Clebsch-Gordan coefficients. https://doi.org/10.1134/s0030400x20080275

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