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Deng et al. Microstructures 2023;3:2023044 https://dx.doi.org/10.20517/microstructures.2023.42 Page 5 of 18

Figure 5. Phase diagram of Mn Cu Ge N. T and T denote the Curie and Néel temperatures, respectively [18] .
C
N
3
1-x
x
Mn Zn Ge N [11,20] . In Mn Cu Sn N, the AFM transition closely coupled with the volume change is
x
x
1-x
3
1-x
3
broadened upon Sn doping, producing the NTE behavior . The characterization of magnetic structures in
[19]
doped systems still requires careful study by neutron scattering.
Non-coplanar magnetic structures
A non-coplanar FIM structure with the propagation vector k = (1/2, 1/2, 0) has been reported in
Mn CuN [54,60] . The magnetic ordering temperature of the Mn CuN compound is 143 K . With cooling, the
[54]
3
3
compound shows a transition from a high-temperature cubic phase to a low-temperature tetragonal phase.
Herein, the magnetic moment direction of Mn atoms in the z = 0 plane is along the [001] direction, while
the atoms in the z = 0.5 plane have two magnetic components, namely the FM arrangement in the [001]
[54]
direction and the “square” AFM arrangement in the z = 0.5 plane . It is worth noting that the
antiperovskite Mn SnC with a magnetic ordering temperature of 294 K has the same type of magnetic
3
structure as Mn CuN. Moreover, as shown in Figure 6A, an orthorhombic magnetic structure model with
3
P symmetry was determined in Mn Cu N . The sub-lattice of a magnetic structure is 2c × 2a × b,
0.96
0.89
3
1
where a, b, and c are nuclear lattice parameters. At 6 K, neutron diffraction revealed that the Mn
moments show an AFM component of 3.65 μ /Mn on the z = 0.5 plane and a FM component of 0.91
B
μ /Mn parallel to the y-axis on the x = 0.25 and 0.75 planes .
[39]
B
Figure 6B gives a non-collinear magnetic structure M-1 of Mn Ga N . The M-1 phase remains 79% in
0.95
3
0.94
coexistence with Γ magnetic configuration between 6 K and 50 K . It can be seen that the sub-lattice of
[35]
5g
the M-1 phase is a, where a is the lattice parameter of the nuclear structure. For the M-1 phase, the
results of neutron diffraction indicate that Mn atoms comprise three different locations, including Mn1 1a
(0, 0, 0), Mn2 2b (0.5, 0.5, 0), and Mn3 4d (0.25, 0.25, 0.5). Mn1 and Mn2 display the AFM components
along the z axis. Mn3 consists of two magnetic components; one is the “square” AFM component on the
plane z = 0.5, and the other one is the FM component along a z axis direction. At 6 K, the AFM moment is
0.89 μ /Mn for Mn1 and Mn2, while Mn3 includes a FM moment of 2.18 μ /Mn and an AFM moment of
B
B
0.7 μ /Mn.
B
Recently, the non-collinear FIM structures were determined in the (1-x)Mn GaN- xMn SbN (0.2 ≤ x ≤ 0.8)
3
3
[61]
heterogeneous system [Figure 6C]. Upon cooling, Mn SbN undergoes a PM-FIM phase transition at
3