Absence of first order magnetic transition, a curious case of Mn3InC

Abstract

The volume expanding magnetostructural transition in Mn${}_3$GaC and Mn${}_3$SnC has been identified to be due to distortion of Mn${}_6$C octahedra. Despite a similar lattice volume as Mn${}_3$SnC and similar valence electron contribution to the density of states as in Mn${}_3$GaC, Mn${}_3$InC does not undergo a first order magnetostructural transformation like the Ga and Sn antiperovskite counterparts. A systematic investigation of its structure and magnetic properties using probes like x-ray diffraction, magnetization measurements, neutron diffraction and extended x-ray absorption fine structure (EXAFS) reveal that though the octahedra are distorted resulting in long and short Mn -- Mn bonds and different magnetic moments on Mn atoms, the interaction between them remains ferromagnetic. This has been attributed to the strain on the Mn${}_6$C octahedra produced due to the relatively larger size of In atom compared to Sn and Ga. The size of In atom constricts the deformation of Mn${}_6$C octahedra giving rise to Mn -- Mn distances that favor only ferromagnetic interactions in the compound.

References in corpus (6)

• Large magnetic entropy change near room temperature in antipervoskite SnCMn3
• Effect of carbon content on magnetostructural properties of Mn${}_3$GaC
• Effect of local structural distortions on magnetostructural transformation in Mn${}_3$SnC
• Effect of composition on magnetocaloric properties of Mn${}_3$Ga${}_{(1-x)}$Sn${}_x$C
• Phase separated magnetic ground state in Mn${}_3$Ga${}_{0.45}$Sn${}_{0.55}$C
• Mechanism of magnetostructural transformation in multifunctional Mn${}_3$GaC