Magnetostructural properties of the versatile ferromagnetic system MnSb

Magnetocaloric materials have attracted significant research attention for potential applications in environmentally friendly solid-state refrigeration and waste-heat recovery technologies. Manganese antimony (MnSb) is a promising magnetocaloric system due to its high refrigerant capacity and the tunability of its magnetic properties through compositional variation, e.g. via incorporation of excess Mn in Mn1+xSb or substitution of Mn with Cr in (Mn,Cr)Sb. As in many magnetocaloric materials, magnetostructural coupling in MnSb is thought to be a key driver of its useful properties. Here, we examine the magnetostructural behavior of stoichiometric MnSb (TC = 577 K) via temperature-dependent x-ray and neutron diffraction and pair distribution function analysis, including with an in-situ magnetic field. The results demonstrate strong magnetoelastic coupling manifested as a pronounced increase in the unit cell volume upon cooling into the ferromagnetic state. Interestingly, the lattice response begins well above the long-range ferromagnetic ordering temperature of 577 K. Through magnetic pair distribution function analysis, we demonstrate that the growth of short-range ferromagnetic correlations above TC drives the magnetoelastic response. The measurements conducted in an in-situ magnetic field demonstrate field-induced magnetostriction in MnSb with a nontrivial temperature dependence. Taken together, these results provide a detailed view of the magnetostructural behavior in this promising magnetocaloric system.