Structural and magnetic properties of Mn3-xCdxTeO6 (x = 0, 1, 1.5 and 2)

TL;DR

This study investigates how substituting Mn with Cd in Mn3TeO6 affects its structure and magnetic properties, revealing that Cd doping lowers the antiferromagnetic transition temperature and induces incommensurate helical magnetic order.

Contribution

It provides new insights into the magnetic structure and doping effects in Mn3TeO6-based ceramics through comprehensive experimental analysis.

Findings

Cd doping replaces Mn without altering overall structure.

Antiferromagnetic transition temperature decreases with more Cd.

Incommensurate helical magnetic order observed in Cd-doped samples.

Abstract

Mn3TeO6 exhibits a corundum-related A3TeO6 structure and a complex magnetic structure involving two magnetic orbits for the Mn atoms [*]. Mn3-xCdxTeO6 (x=0, 1, 1.5 and 2) ceramics were synthesized by solid state reaction and investigated using X-ray powder diffraction, electron microscopy, calorimetric and magnetic measurements. Cd2+ replaces Mn2+ cations without greatly affecting the structure of the compound. The Mn and Cd cations were found to be randomly distributed over the A-site. Magnetization measurements indicated that the samples order antiferromagnetically at low temperature with a transition temperature that decreases with increasing Cd doping. The nuclear and magnetic structure of one specially prepared 114Cd containing sample: Mn1.5(114Cd)1.5TeO6, was studied using neutron powder diffraction over the temperature range 2 to 295 K. Mn1.5(114Cd)1.5TeO6 was found to order in an incommensurate helical magnetic structure, very similar to that of Mn3TeO6 [*]. However, with a lower transition temperature and the extension of the ordered structure confined to order 240(10) {\AA}. [*] S. A. Ivanov et al. Mater. Res. Bull. 46 (2011) 1870.