Mott physics in $2p$ electron dioxygenyl magnet : O$_{2}$$M$F$_{6}$ ($M$=Sb, Pt)

TL;DR

This paper investigates the electronic and magnetic properties of O$_{2}$$M$F$_{6}$ compounds, revealing how Coulomb correlations and spin-orbit interactions induce Mott insulating states in these strongly correlated electron systems.

Contribution

It demonstrates that Coulomb interactions and spin-orbit coupling collaboratively induce Mott insulating states in O$_{2}$$M$F$_{6}$, highlighting the role of spin-orbit effects similar to Sr$_{2}$IrO$_{4}$.

Findings

Coulomb correlation drives Mott insulating state in O$_{2}$SbF$_{6}$.

Combined Coulomb and spin-orbit effects induce Mott insulator in O$_{2}$PtF$_{6}$.

Spin-orbit interaction plays a key role similar to Sr$_{2}$IrO$_{4}$.

Abstract

We have investigated electronic structures and magnetic properties of O$_{2}$$M$F$_{6}$ ($M$=Sb, Pt), which are composed of two building blocks of strongly correlated electrons: O$_{2}^{+}$ dioxygenyls and $M$F$_{6}^{-}$ octahedra, by employing the first-principles electronic structure band method. For O$_{2}$SbF$_{6}$, as a reference system of O$_{2}$PtF$_{6}$, we have shown that the Coulomb correlation of O(2$p$) electrons drives the Mott insulating state. For O$_{2}$PtF$_{6}$, we have demonstrated that the Mott insulating state is induced by the combined effects of the Coulomb correlation of O(2$p$) and Pt(5$d$) electrons and the spin-orbit (SO) interaction of Pt(5$d$) states. The role of the SO interaction in forming the Mott insulating state of O$_{2}$PtF$_{6}$ is similar to the case of Sr$_{2}$IrO$_{4}$ that is a prototype of a SO induced Mott system with J$_{eff}=1/2$.