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arXiv · 1610.04280

On the calculation of second-order magnetic properties using subsystem approaches in the relativistic framework

Malgorzata Olejniczak·Radovan Bast·Andre Severo Pereira Gomes
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Abstract

We report an implementation of the nuclear magnetic resonance (NMR) shielding ($\sigma$), isotope-independent indirect spin-spin coupling ($K$) and the magnetizability ($\xi$) tensors in the frozen density embedding (FDE) scheme using the four-component (4c) relativistic Dirac--Coulomb (DC) Hamiltonian and the non-collinear spin density functional theory (SDFT). The formalism takes into account the magnetic balance between the large and the small components of molecular spinors and assures the gauge-origin independence of NMR shielding and magnetizability results. This implementation has been applied to hydrogen-bonded HXH$\cdots$OH$_2$ complexes (X = Se, Te, Po) and compared with the supermolecular calculations and with the approach based on the integration of the magnetically induced current density vector. A comparison with the approximate Zeroth-Order Regular Approximation (ZORA) Hamiltonian indicates non-negligible differences in $\sigma$ and $K$ in the HPoH$\cdots$OH$_2$ complex, and calls for a thourough comparison of ZORA and DC in the description of environment effects on NMR parameters for molecular systems with heavy elements.

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Malgorzata Olejniczak, Radovan Bast, Andre Severo Pereira Gomes. 2016-10-13. On the calculation of second-order magnetic properties using subsystem approaches in the relativistic framework. https://doi.org/10.1039/c6cp08561j

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