Effect of local structural distortions on magnetostructural transformation in Mn$_3$SnC

TL;DR

This study investigates how local structural distortions influence the magnetostructural transformation in Mn$_3$SnC, revealing a connection between distortions in Mn$_6$C octahedra and magnetic ground states, with implications for cooling applications.

Contribution

It provides new insights into the role of local structural distortions in the magnetostructural transition of Mn$_3$SnC, combining diffraction and spectroscopy techniques.

Findings

Transformation occurs near room temperature (~280K).

Structural distortions in Mn$_6$C octahedra affect magnetic ground states.

Large magnetic entropy change suggests potential for ferroic cooling.

Abstract

In this paper we attempt to understand the different nature of first order magnetic transformation in Mn$_3$SnC as compared to that in Mn$_3$GaC. The transformation in Mn$_3$SnC is close to room temperature (T$_t \approx$ 280K) and is associated with a large change in magnetic entropy that makes it a suitable candidate for applications in ferroic cooling. Using a combination of x-ray and neutron diffraction and x-ray absorption fine structure (XAFS) spectroscopy we infer that the magnetic ground state consisting of antiferromagnetic and ferromagnetic Mn atoms is due to structural distortions present in Mn$_6$C octahedra.