Crystal and magnetic structure of antiferromagnetic Mn₂PtPd

Abstract

We have investigated the crystal and magnetic structure of MnPtPd alloy using powder x-ray and neutron diffraction experiments. This compound is believed to belong to the Heusler family having crystal symmetry I4/mmm (TiAl-type). However, in this work we found that the Pd and Pt atoms are disordered and thus MnPtPd crystallizes in the L1 structure having P4/mmm symmetry (CuAu-I type) like MnPt and MnPd binary alloys. The lattice constants are a = 2.86 Å and c = 3.62 Å at room temperature. MnPtPd has a collinear antiferromagnetic spin structure below the Néel temperature T = 866 K, where Mn moments of ~4 µ lie in the ab-plane. We observed a strong change in the lattice parameters near T . The sample exhibits metallic behaviour, where electrical resistivity and carrier concentration are of the order of 10 Ω cm and 10 cm, respectively.

Investigation of electronic, magnetic, elastic, mechanical, thermodynamic, and thermoelectronic properties of Mn2PtV Heusler alloy: ab initio study

“…In this chemical formula X 2 YZ with a composition of 2:1:1, X and Y are usually transition metal elements and Z may be a group 3, 4, or 5 element [1]. Nowadays, as the search for new and novel magnetic materials is at its peak, the Z element which is in normal case is a group 3, 4, or 5 element in X 2 YZ is being replaced by transition elements [2]. Therefore, in this case, all the constituent elements belong to transition series.…”