The antiferromagnetic insulator Ca3FeRhO6: characterization and electronic structure calculations

TL;DR

This study combines experimental and theoretical methods to characterize the antiferromagnetic insulator Ca3FeRhO6, revealing its magnetic properties, electronic structure, and confirming the Fe 3+ high-spin state through susceptibility, spectroscopy, transport measurements, and band structure calculations.

Contribution

First comprehensive investigation of Ca3FeRhO6's magnetic and electronic properties using both experiments and LSDA calculations.

Findings

Neel temperature T_N = 20 K

Fe ions are in a 3+ high-spin state

Activation energy of 0.2 eV from transport measurements

Abstract

We investigate the antiferromagnetic insulating nature of Ca3FeRhO6 both experimentally and theoretically. Susceptibility measurements reveal a Neel temperature T_N = 20 K, and a magnetic moment of 5.3 muB/f. u., while Moessbauer spectroscopy strongly suggests that the Fe ions, located in trigonal prismatic sites, are in a 3+ high spin state. Transport measurements display a simple Arrhenius law, with an activation energy of 0.2 eV. The experimental results are interpreted with LSDA band structure calculations, which confirm the Fe 3+ state, the high-spin/low-spin scenario, the antiferromagnetic ordering, and the value for the activation energy.