# DFT+DMFT study on soft moment magnetism and covalent bonding in SrRu$_2$O$_6$

## TL;DR

This study uses dynamical mean-field theory to analyze the magnetic and bonding properties of SrRu$_2$O$_6$, revealing the interplay of Mott and covalent insulator states influenced by Hund's coupling.

## Contribution

The paper presents a detailed DMFT analysis of SrRu$_2$O$_6$, highlighting the role of Hund's coupling and covalent bonding in its magnetic behavior, with minimal spin-orbit effects.

## Key findings

- Identification of Mott and covalent insulator phases depending on Hund's coupling.
- Explanation of the absence of Curie susceptibility in the paramagnetic phase.
- Observation of a single phase with smoothly varying properties at high temperatures.

## Abstract

Dynamical mean-field theory is used to study the three orbital model of the $d^3$ compound SrRu$_2$O$_6$ both with and without explicitly including the O-$p$ states. Depending on the size of the Hund's coupling $J$, at low to intermediate temperatures we find solutions corresponding to Mott or correlated covalent insulator. The latter can explain the experimentally observed absence of Curie susceptibility in the paramagnetic phase. At high temperatures a single phase with smoothly varying properties is observed. SrRu$_2$O$_6$ provides an ideal system to study the competition between the local moment physics and covalent bonding since both effects are maximized, while spin-orbit interaction is found to play a minor role.