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



















                                   Figure 1. (A) Perovskite structure ABO ; (B) antiperovskite structure Mn XN.
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                                   Figure 2. The collinear (A) AFM structure and (B) FM structure of Mn GaC.
                                                                                  3
               Mn GaC is k = (0, 0, 0), displaying m = 1.3  ± 0.1  μ /Mn at 193 K [53,54] . The direction [111] of easy
                                                              B
                  3
                                                              [56]
               magnetization is also confirmed by the Mössbauer effect .
               Mn ZnN is characterized by two first-order magnetic transitions: PM-AFM at 183 K and AFM-AFM at
                  3
               140 K. As shown in Figure 3A, the low temperature AFM phase is collinear within a    2a sub-lattice
               of manganese, exhibiting two inequivalent magnetic atoms with different ordered magnetic moments .
                                                                                                       [57]
               The values of moments 0.61  μ  on Mn1 (000) and 1.03  μ  on Mn2 (1/4, 1/4, 1/4) were clarified by
                                                                   B
                                           B
               Fruchart et al. . In 2012, we determined the ordered moments of 1.40 μ  on Mn1 and 2.44 μ  on Mn2 at
                           [58]
                                                                              B
                                                                                               B
               80 K for Mn Zn N by neutron diffraction . Moreover, for Mn Zn N , we observed a collinear FIM
                                                    [20]
                                                                      3.19
                                                                           0.77
                                                                              0.94
                             0.99
                          3
               structure with a propagation vector k = (0, 0, 0) below 200 K [Figure 3B]. The magnetic moments alternate
               along the [111] direction with different values, corresponding to 0.5(1) (face-centered atom) and
               1.3(7) (corner atom) μ /Mn for Mn atoms at 120 K .
                                                          [21]
                                  B
               Non-collinear magnetic structures
               It is worth noting that two non-collinear AFM phases belonging to Γ  and Γ  types, respectively, have been
                                                                                5g
                                                                         4g
               studied extensively in antiperovskites. In this case, the compounds remain cubic with the propagation
                                    5g
               vector k = (0, 0, 0). For Γ  type shown in Figure 4A, the magnetic moments of Mn atoms are located in the
               (111) plane with a triangular arrangement. As seen from Figure 4B, the magnetic moments of Γ  are
                                                                                                     4g
                                                                                                  4g
                                                                                                         5g
               triangularly located in the (111) plane achieved by rotating 90° coherently from Γ  type. In Γ  and Γ
                                                                                        5g
               magnetic structures, two Mn atoms form an angle of 120° with each other in the (111) plane, and the
               magnetic moments of the three atoms cancel each other out to generate a zero net magnetic moment.
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