Abstract
Symmetry analysis of possible magnetic structures with k = 0 and of phase transitions is described for the metallic perovskites Mn3MN (M = Ni, Ga, Ag, Sn, Zn). The phase transition from a triangular antiferromagnetic structure to a triangular noncomplanar structure is considered phenomenologically in detail. Theoretical results are shown to be in good qualitative and quantitative agreement with the experimental data.