Investigating solvent effects on the magnetic properties of molybdate ions (MoO₄^2-) with relativistic embedding

Loïc Halbert (1) , Małgorzata Olejniczak (2) , Valérie Vallet (1) , André Severo Pereira Gomes (1)

1 PCMT - Physico-Chimie Moléculaire Théorique
2 Centre of New Technologies

We investigate the ability of mechanical and electronic density functional theory‐based embedding approaches to describe the solvent effects on nuclear magnetic resonance (NMR) shielding constants of the ⁹⁵Mo nucleus in the molybdate ion in aqueous solution. From the description obtained from calculations with two‐ and four‐component relativistic Hamiltonians, we find that, for such systems, spin‐orbit coupling effects are clearly important for absolute shielding values, but for relative quantities, a scalar relativistic treatment provides sufficient estimation of the solvent effects. We find that the electronic contributions to the solvent effects are relatively modest yet decisive to provide a more accurate magnetic response of the system when compared to reference supermolecular calculations. We analyze the errors in the embedding calculations by statistical methods, as well as through a real‐space representation of NMR shielding densities, which are shown to provide a clear picture of the physical processes at play.

Mots clés: molybdate; shielding density; relativistic effects; solvation; NMR shielding; quantum embedding

Domaines: Chimie théorique et/ou physique; Chimie-Physique [physics.chem-ph]

Loïc Halbert, Małgorzata Olejniczak, Valérie Vallet, André Severo Pereira Gomes. Investigating solvent effects on the magnetic properties of molybdate ions (MoO₄^2-) with relativistic embedding. International Journal of Quantum Chemistry, 2020, pp.e26207. ⟨10.1002/qua.26207⟩. ⟨hal-02413336⟩