Symmetry Breaking of Relativistic Multiconfiguration Methods in the Nonrelativistic Limit
نویسندگان
چکیده
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 or S. We thereby complement and clarify some previous studies.
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