abstract

• First-principles calculations are conducted to investigate the magnetic properties of the Na2IrO3 compounds. We reveal that the Na2IrO3%27s local structural distortions are essential for an accurate description of the magnetism of such systems. They provide a feasible explanation for the experimentally observed antiferromagnetic zigzag magnetic ground state. We demonstrate that the underlying competition between the spin-orbit coupling and the crystal-field splitting rules the crystal structure and profoundly influences the strength of the magnetic exchange interactions. We unambiguously identify that the D4h-type distortions, due to the Jahn-Teller effect, are disclosed in an elongation along the IrO6 polyhedra%27s apical axis in the ac plane. On the other hand, the Ir atoms off-centering in the basal plane (perpendicular to the local D4h elongation axis) arises owing to an inhomogeneous cationic charge distribution of Ir4%2b/Na%2b in the transition-metal layer resulting in both effects being decisive in controlling the magnetism of Na2IrO3 together with the spin-orbit interactions. © 2022 American Physical Society.

authors

• Ruiz Díaz Pedro
• Saubanère M.

publication date

• 2022-01-01

funding provided via

• Laboratorio Nacional de Supercómputo del Sureste de México (LNS) Project No. 201703117n; SEP-CONACYT Mexico-ANUIES-ECOS NORD France Grant No. 296636/M18P02  Grant

published in

• Physical Review B  Journal

keywords

• Calculations; Crystal structure; Ground state; Magnetism; Sodium compounds; Transition metals; Basal planes; Basal-planes; Cationic charges; Crystal field splittings; Crystals structures; First principle calculations; Magnetic exchange interactions; Magnetic ground state; Spin-orbit couplings; Structural distortions; Iridium compounds

Digital Object Identifier (DOI)

• 10.1103/PhysRevB.105.094413

PubMed ID

start page

end page

volume

• 105

issue

• 9