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arXiv · 2504.19479

Relativistic Two-Electron Contributions within Exact Two-Component Theory

Xubo Wang·Chaoqun Zhang·Junzi Liu·Lan Cheng
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Abstract

The development of relativistic exact two-component (X2C) theory is briefly reviewed, with an emphasis on cost-effective treatments of relativistic two-electron contributions by means of model potential (MP) techniques and closely related atomic mean-field (AMF) approaches. The correct MP or AMF contribution to the electronic energy is elucidated. The performance of one-center approximations to relativistic two-electron contributions is carefully assessed using benchmark calculations of molecular properties.

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Xubo Wang, Chaoqun Zhang, Junzi Liu, Lan Cheng. 2025-04-28. Relativistic Two-Electron Contributions within Exact Two-Component Theory. https://arxiv.org/abs/2504.19479

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