High-pressure synthesis and spin glass behavior of a Mn/Ir disordered quadruple perovskite CaCu3Mn2Ir2O12

TL;DR

This study reports the synthesis of a novel Mn/Ir disordered quadruple perovskite oxide, CaCu3Mn2Ir2O12, exhibiting spin glass behavior due to competing magnetic interactions among its transition metal ions.

Contribution

It introduces a new high-pressure synthesis method for a hybridized quadruple perovskite with unique Mn/Ir disorder and magnetic properties.

Findings

Crystallizes in an Im-3 space group with ordered Ca and Cu.

Mn and Ir ions are disordered with +4 charge states.

Displays spin glass behavior due to competing magnetic interactions.

Abstract

A new 3d-5d hybridized quadruple perovskite oxide, CaCu3Mn2Ir2O12, was synthesized by high-pressure and high-temperature methods. The Rietveld structure analysis reveals that the compound crystallizes in an AA'3B4O12-type perovskite structure with space group Im-3, where the Ca and Cu are 1:3 ordered at fixed atomic positions. At the B site the 3d Mn and the 5d Ir ions are disorderly distributed due to a rare equal +4 charge states for both of them as determined by X-ray absorption spectroscopy. The competing antiferromagnetic and ferromagnetic interactions among Cu2+, Mn4+, and Ir4+ ions give rise to spin glass behavior, which follows a conventional dynamical slowing down model.