$J_{eff}=1/2$ Mott Insulating State in Rh and Ir Fluorides

TL;DR

This paper predicts a new class of $J_{eff}=1/2$ Mott insulators in fluoride compounds using advanced computational methods, highlighting their large gaps and proximity to ideal symmetry, which are crucial for understanding SOC and electron correlation effects.

Contribution

It introduces a previously overlooked family of fluoride compounds as $J_{eff}=1/2$ Mott insulators, expanding the class of materials with strong spin-orbit coupling and electron correlation.

Findings

Large Mott gaps in predicted compounds

Some compounds exhibit near-perfect $SU(2)$ symmetry

Potential for new quantum states in fluoride materials

Abstract

Discovery of new transition metal compounds with large spin orbit coupling (SOC) coexisting with strong electron-electron correlation among the $d$ electrons is essential for understanding the physics that emerges from the interplay of these two effects. In this study, we predict a novel class of $J_{eff}=1/2$ Mott insulators in a family of fluoride compounds that are previously synthesized, but not characterized extensively. First principles calculations in the level of all electron Density Functional Theory + Dynamical Mean Field Theory (DFT+DMFT) indicate that these compounds have large Mott gaps and some of them exhibit unprecedented proximity to the ideal, $SU(2)$ symmetric $J_{eff}=1/2$ limit.