Strong antiferromagnetic interaction owing to a large trigonal distortion in the spin-orbit-coupled honeycomb lattice iridate CdIrO${}_3$

Abstract

We investigated the magnetic properties of the ilmenite-type iridate CdIrO${}_3$ with a honeycomb lattice formed by Ir${}^{4+}$ ions prepared via a solid-state metathesis. The magnetization measurements with using the powder sample reveal a large effective magnetic moment and a fairly strong antiferromagnetic interaction, indicating a deviation from the Kitaev model. Considering the relationship between magnetism and crystal structure in CdIrO${}_3$ with comparing with the other ilmenite-type iridates ZnIrO${}_3$ and MgIrO${}_3$, we conclude that insulating CdIrO${}_3$ cannot be describe as a $J_{\mathrm{eff}}=1/2$ Mott state owing to a metathetically-stabilized large trigonal distortion of IrO${}_6$ octahedra.

6 pages, 4 figures, accepted for publication in Physical Review Materials