KAgF3: quasi-one-dimensional magnetism in three-dimensional magnetic ions sublattice

TL;DR

This study investigates the electronic and magnetic properties of KAgF3, revealing significant quasi-one-dimensional antiferromagnetism driven by orbital ordering, despite its three-dimensional ion sublattice.

Contribution

It provides the first detailed analysis of the quasi-one-dimensional magnetism in KAgF3 using first-principles calculations, highlighting the role of orbital ordering.

Findings

KAgF3 exhibits strong quasi-one-dimensional antiferromagnetism.

Orbital ordering of Ag2+ ions drives the magnetic behavior.

The insulating state is mainly due to on-site Coulomb repulsion.

Abstract

The electronic structure and magnetic properties of the Jahn-Teller-distorted perovskite KAgF3 have been investigated using the full-potential linerized aug- mented plane-wave method. It is found that KAgF3 exhibits significant quasi-one- dimensional antiferromagnetism with the ratio of exchange constant jJ?j (perpen- dicular to the z axis) and J (along the z axis) about 0.04, although the sublattice of magnetic ion is three-dimensional. The strong quasi-one-dimensional antiferromag- netism originates from the C-antiferro-distortive orbital ordering of the Ag2+ 4d9 ions. The orbital ordered antiferromagnetic insulating state in KAgF3 is determined by on-site Coulomb repulsion to a large extent.