title: On the calculation of second-order magnetic properties using subsystem approaches in a relativistic framework.
abstract: We report an implementation of nuclear magnetic resonance (NMR) shielding (σ), isotope-independent indirect spin-spin coupling (K) and the magnetizability (ξ) tensors in a frozen density embedding scheme using the four-component (4c) relativistic Dirac-Coulomb (DC) Hamiltonian and non-collinear spin density functional theory. 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 the NMR shielding and magnetizability results. This implementation has been applied to hydrogen-bonded HXHOH2complexes (X = Se, Te, Po) and compared with supermolecular calculations and with an 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 σ and K in the HPoHOH2complex, and calls for a thorough comparison of ZORA and DC Hamiltonians in the description of environment effects on NMR parameters for molecular systems with heavy elements.
authors.affiliation: Université de Lille, CNRS, UMR 8523 - PhLAM - Physique des Lasers, Atomes et Molécules, F-59000 Lille, France. gosia.olejniczak@univ-lille1.fr andre.gomes@univ-lille1.fr.
authors.forename: Małgorzata
authors.initials: M
authors.lastname: Olejniczak
authors.affiliation: High Performance Computing Group, UiT The Arctic University of Norway, N-9037 Tromsø, Norway. radovan.bast@uit.no.
authors.forename: Radovan
authors.initials: R
authors.lastname: Bast
authors.affiliation: Université de Lille, CNRS, UMR 8523 - PhLAM - Physique des Lasers, Atomes et Molécules, F-59000 Lille, France. gosia.olejniczak@univ-lille1.fr andre.gomes@univ-lille1.fr.
authors.forename: André Severo
authors.identifier: http://orcid.org/0000-0002-5437-2251
authors.initials: AS
authors.lastname: Pereira Gomes