Thermodynamic, Electromagnetic, and Lattice Properties of Antiperovskite Mn3SbN

The physical properties of polycrystalline Mn3SbN were investigated using measurements of the magnetic, calorimetric, and electronic transport properties. At room temperature, the phase crystallizes in a tetragonal structure with symmetry. A remarkably sharp peak in the heat capacity versus temperature curve was found near 353？K. The peak reaches 723？J？mol？1？K？1 at its highest, which corresponds to a transition entropy of 10.2？J？mol？1？K？1. The majority of the large entropy change appears to be due to lattice distortion from the high-temperature cubic structure to the room-temperature tetragonal structure and the accompanying Ferrimagnetic transition. 1. Introduction Antiperovskite compounds with the formula Mn3XN or Mn3XC (X = Cu, Zn, Ga, Cu, In, or Sn) were discovered in the middle of the last century [1]. Recently, interest in these materials has intensively renewed owing to discoveries of new, potentially useful properties [2–4] such as the giant magnetoresistance of Mn3GaC [5], negative thermal expansion (NTE) of Mn3Cu(Ge)N [6] and Mn3Zn(Ge)N [7], magnetostriction of Mn3CuN [8] and Mn3SbN [9], and near-zero temperature coefficient of the resistivity of Mn3CuN [10] and Mn3NiN [11]. Specifically, Takenaka and Takagi found that Ge-doped Mn3CuN compound has a large NTE (NTE parameter = ？25 × 10？6？K？1) [12]; using neutron diffraction, the broad NTE was determined to be associated with the local T4 structure [6]. Asano et al. discovered large magnetostriction in tetragonal Mn3CuN; it expands 0.2% and shrinks 0.1% in the directions parallel and perpendicular to an external 90？kOe magnetic field, respectively [8]. In previous studies, we found a peculiar phase separation and accompanying anomaly in the electronic transport properties of Mn3ZnN [13, 14], while further study indicated that the thermal expansion properties of Mn3ZnN can be controlled by introducing Zn vacancies [15]. In addition, Song et al. observed a canonical spin-glass state in Mn3GaN below the spin-freezing temperature of 133？K [16]. Lukashev et al. systematically studied the spin density of the spin-frustrated state of a Mn-based antiperovskite under mechanical stress [17]. The above-mentioned properties enable a variety of potential applications for this type of material. Although the prospective industrial markets are expected to be large and much effort has already been devoted to studying their structural, electromagnetic, and transport properties, further investigations on antiperovskite materials are still required. In this study, the thermodynamic, electromagnetic, and electronic