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arXiv · 0910.3932

Symmetry Breaking of Relativistic Multiconfiguration Methods in the Nonrelativistic Limit

Maria J. Esteban·Mathieu Lewin·Andreas Savin
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Abstract

The multiconfiguration Dirac-Fock method allows to calculate the state of relativistic electrons in atoms or molecules. This method has been known for a long time to provide certain wrong predictions in the nonrelativistic limit. We study in full mathematical details the nonlinear model obtained in the nonrelativistic limit for Be-like atoms. We show that the method with sp+pd configurations in the J=1 sector leads to a symmetry breaking phenomenon in the sense that the ground state is never an eigenvector of L^2 or S^2. We thereby complement and clarify some previous studies.

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Maria J. Esteban, Mathieu Lewin, Andreas Savin. 2010-02-05. Symmetry Breaking of Relativistic Multiconfiguration Methods in the Nonrelativistic Limit. https://doi.org/10.1088/0951-7715%2F23%2F4%2F001

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