# Orbital angular momentum constraints in the variational optimization of the two-electron reduced-density matrix

@article{Li2019OrbitalAM, title={Orbital angular momentum constraints in the variational optimization of the two-electron reduced-density matrix}, author={Run R Li and A. Eugene DePrince}, journal={Physical Review A}, year={2019} }

The direct variational determination of the two-electron reduced-density matrix (2-RDM) is usually carried out under the assumption that the 2-RDM is a real-valued quantity. However, in systems that possess orbital angular momentum symmetry, the description of states with a well-defined, non-zero z-projection of the orbital angular momentum requires a complex-valued 2-RDM. We consider a semidefinite program suitable for the direct optimization of a complex-valued 2-RDM and explore the role of…

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