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DOE OSTI · 22660743

A state interaction spin-orbit coupling density matrix renormalization group method

Sayfutyarova, Elvira R.·Chan, Garnet Kin-Lic
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Abstract

We describe a state interaction spin-orbit (SISO) coupling method using density matrix renormalization group (DMRG) wavefunctions and the spin-orbit mean-field (SOMF) operator. We implement our DMRG-SISO scheme using a spin-adapted algorithm that computes transition density matrices between arbitrary matrix product states. To demonstrate the potential of the DMRG-SISO scheme we present accurate benchmark calculations for the zero-field splitting of the copper and gold atoms, comparing to earlier complete active space self-consistent-field and second-order complete active space perturbation theory results in the same basis. We also compute the effects of spin-orbit coupling on the spin-ladder of the iron-sulfur dimer complex [Fe{sub 2}S{sub 2}(SCH{sub 3}){sub 4}]{sup 3−}, determining the splitting of the lowest quartet and sextet states. We find that the magnitude of the zero-field splitting for the higher quartet and sextet states approaches a significant fraction of the Heisenberg exchange parameter.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICSDENSITY MATRIXINTERACTIONSL-S COUPLINGMEAN-FIELD THEORYPERTURBATION THEORYRENORMALIZATIONSELF-CONSISTENT FIELDWAVE FUNCTIONS

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Sayfutyarova, Elvira R., Chan, Garnet Kin-Lic. 2016-06-21. A state interaction spin-orbit coupling density matrix renormalization group method. https://doi.org/10.1063/1.4953445

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