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Page 2 of 18 Deng et al. Microstructures 2023;3:2023044 https://dx.doi.org/10.20517/microstructures.2023.42

INTRODUCTION
Since the 1980s, compounds with perovskite structures have become one of the focuses in both materials
science and condensed matter physics because of their fascinating physical properties and potential
functionalities. These properties include superconductivity, multiferroics, colossal magnetoresistance,
[1-4]
negative thermal expansion (NTE), etc. . In the antiperovskite compounds (antiperovskites) similar to the
perovskite structure, numerous interesting physical properties have also been observed, such as NTE [5-25] ,
giant magnetoresistance [26-27] , anomalous Hall effect [28-30] , piezomagnetic/baromagnetic effects [23,31-35] ,
magnetocaloric effect [36-39] , barocaloric effect [40,41] , nearly zero temperature coefficient of resistivity [42-46] ,
superconductivity [47,48] , etc. Therefore, antiperovskites have gained significant attention. Nevertheless, the
understanding of these abnormal physical properties is still in the exploratory stage, and the accumulation
of experimental data and further deepening of theoretical research are required.

The so-called antiperovskite structure refers to a structure that is similar to perovskite. As shown in
Figure 1, the face-centered position occupied by non-metallic elements, such as oxygen, in the original
perovskite structure is occupied by transition group element atoms M, especially the magnetic element
M = Mn, Fe, Ni, etc. The body center position originally occupied by metal elements is occupied by non-
metallic elements N or C, and the original vertex position is occupied by metal element X, thus forming a
lattice belonging to a cubic unit cell with chemical formula M XN(C) (M = Mn, Fe, Ni; X = Zn, Ga, Cu, Al,
3
In, Sn). Among them, face-centered magnetic atoms (such as Mn) and body-centered N (C) atoms can form
NMn or CMn octahedra, and six magnetic atoms Mn are located at the six corners of the octahedron,
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which is prone to magnetic frustration. Thereby it generates the abounding magnetic structures, including
collinear antiferromagnetic (AFM), collinear ferromagnetic (FM), collinear ferrimagnetic (FIM), non-
collinear magnetic, and non-coplanar magnetic spin configurations [49-51] . On the other hand, the abundant
magnetic structures in antiperovskite Mn XN(C) compounds are very sensitive to changes in temperature,
3
magnetic field, pressure, composition, and grain size. Its abnormal lattice change, magnetic phase transition,
and electronic transport properties are interrelated and affect each other, showing its rich physical
properties.

In this paper, we will summarize the magnetic structures and correlated physical properties in
antiperovskites. We present the potential application of antiperovskites as novel materials in various
emerging fields. In order to further optimize performance and explore mechanisms, the issues such as
exploration of new magnetic structures, synthesis of single crystal samples, and practical application
research for the in-depth research are deserved in the part of outlook.

MAGNETIC STRUCTURES IN MN-BASED ANTIPEROVSKITES
The research on the magnetic structures of antiperovskites mainly focuses on Mn-based compounds.
Herein, the collinear, non-collinear, and non-coplanar magnetic structures in Mn-based antiperovskites will
be introduced in this review.

Collinear magnetic structure
Both collinear AFM and collinear FM structures were determined by neutron diffraction in Mn GaC as
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early as the 1970s. Upon warming, Mn GaC displays several magnetic phase transitions: an AFM-
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intermediate (AFM-IM) phase transition at 160.1 K, an intermediate-FM (IM-FM) phase transition at
163.9 K, and a FM-paramagnetic (FM-PM) transition at 248 K . As shown in Figure 2A, the determined
[52]
magnetic moments m of AFM Mn GaC alternates along the [111] direction with a propagation vector
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k = (1/2, 1/2, 1/2), corresponding to m = 1.8 ± 0.1 μ /Mn at 4.2 K reported by Fruchart et al. and
B
m = 1.54 μ /Mn at 150 K revealed by Çakır et al. [53-55] . As seen from Figure 2B, the propagation vector for FM
B