2025/12/16 by Shaun O’Donnell, C. Regier, O'Donnell, Shaun +17
Materials Science · #FOS: Physical sciences #Heusler alloys: electronic and magnetic properties #Machine Learning in Materials Science #Materials Science (cond-mat.mtrl-sci) #Thermal Expansion and Ionic Conductivity
paper · pdf · doi:10.48550/arxiv.2512.14571
openalex publication_date 2025/12/16 · openalex created_date 2025/12/18 · openalex updated_date 2026/08/01
The crystal and magnetic structures of the nitride antiperovskite Mn3GeN reveals ferrimagnetic order stemming from a distorted kagome-derived lattice of the Mn atoms. Polycrystalline Mn3GeN was synthesized via a solid-state reaction and characterized using neutron powder diffraction, DC magnetometry, and first-principles calculations. Rietveld refinement reveals near-stoichiometric composition (Mn3GeN0.94(1)) adopting a tetragonal I4/mcm structure at T = 500 K and below, featuring axially distorted and tilted [NMn6] octahedra that result in a buckled Mn kagome lattice. On heating, the tetragonal distortion and octahedral tilt angle decrease continuously before transitioning to the cubic Pm3m antiperovskite phase at T ≈ 524 K. Neutron diffraction and magnetometry together reveal noncollinear ferrimagnetic ordering. For 30 K ≤ T ≤ 500 K, the magnetic structure is described by a single propagation vector, k = (0, 0, 0), with inequivalent Mn1 and Mn2 sublattices that couple antiferromagnetically to yield a net moment. Density functional theory-based calculations show the different local moments originate from the bandwidths associated with the distinct Mn-N bond lengths. The temperature dependence of the sublattice moments indicates a compensation-like crossover between Mn1- and Mn2-derived magnetization near 380 K. These findings uncover a previously unrecognized subtlety in the magnetic and structural behavior of Mn3GeN, highlighting the interplay between structural distortions, magnetic ordering, and electronic structure in kagome-derived antiperovskite materials.