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arXiv · 2001.03226

Theoretical Prediction of Magnetic Exchange Coupling Constants from Broken-Symmetry Coupled Cluster Calculations

Henry F. Schurkus·Dian-Teng Chen·Hai-Ping Cheng·Garnet Kin-Lic Chan·John F. Stanton
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Abstract

Exchange coupling constants ($J$) are fundamental to the understanding of spin spectra of magnetic systems. Here we investigate the broken-symmetry (BS) approaches of Noodleman and Yamaguchi in conjunction with coupled cluster (CC) methods to obtain exchange couplings. $J$ values calculated from CC in this fashion converge smoothly towards the FCI result with increasing level of CC excitation. We compare this BS-CC scheme to the complementary EOM-CC approach on a selection of bridged molecular cases and give results from a few other methodologies for context.

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Henry F. Schurkus, Dian-Teng Chen, Hai-Ping Cheng, Garnet Kin-Lic Chan, John F. Stanton. 2020-01-09. Theoretical Prediction of Magnetic Exchange Coupling Constants from Broken-Symmetry Coupled Cluster Calculations. https://doi.org/10.1063/1.5144696

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