Short-range spin order and frustrated magnetism in Mn2InSbO6 and Mn2ScSbO6

TL;DR

This study investigates the crystal structure and magnetic behavior of Mn2InSbO6 and Mn2ScSbO6, revealing short-range magnetic order and the influence of A-site cations in complex corundum-related oxides.

Contribution

It provides detailed structural and magnetic characterization of Mn2ASbO6 compounds, highlighting the presence of short-range magnetism despite high Mn content.

Findings

No long-range magnetic order at 1.6 K

Presence of weak diffuse magnetic peaks

Structural stability down to low temperatures

Abstract

The complex metal oxides Mn2ASbO6 (A=In, Sc) with a corundum-related structure A3BO6 have been prepared as polycrystalline powders by a solid state reaction route. The crystal structure and magnetic properties have been investigated using a combination of X-ray and neutron powder diffraction, electron microscopy, calorimetric and magnetic measurements. At room temperature these compounds adopt a trigonal structure, space group R-3 with a = 8.9313(1) {\AA}, c = 10.7071(2) {\AA} (for In) and a = 8.8836(1) {\AA}, c = 10.6168(2) {\AA} (for Sc) which persists down to 1.6 K. The Mn and A cations were found to be randomly distributed over the A-sites. The overall behavior of the magnetization of Mn2InSbO6 and Mn2ScSbO6 is quite similar. In spite of the relatively large amount of Mn ions on the A-site, only short-ranged magnetism is observed. Neutron diffraction patterns of Mn2InSbO6 showed no evidence of a long-range magnetic ordering at 1.6 K, instead only a weak diffuse magnetic peak was observed at low temperatures. The factors governing the observed structural and magnetic properties of Mn2ASbO6 are discussed and compared with those of other Mn-containing complex metal oxides with a corundum-related structure. The influence of the A-cation sublattice on magnetic properties is also considered.