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Alternative Mathematical Technique to Determine LS Spectral Terms

Renjun Xu·Zhenwen Dai
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Abstract

We presented an alternative computational method for determining the permitted LS spectral terms arising from $l^N$ electronic configurations. This method makes the direct calculation of LS terms possible. Using only basic algebra, we derived our theory from LS-coupling scheme and Pauli exclusion principle. As an application, we have performed the most complete set of calculations to date of the spectral terms arising from $l^N$ electronic configurations, and the representative results were shown. As another application on deducing LS-coupling rules, for two equivalent electrons, we deduced the famous Even Rule; for three equivalent electrons, we derived a new simple rule.

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Renjun Xu, Zhenwen Dai. 2005-10-30. Alternative Mathematical Technique to Determine LS Spectral Terms. https://doi.org/10.1088/0953-4075/39/16/007

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