Revealing the Magnetic Structure and Properties of Mn(Co,Ge)(2)

[Image: see text] The atomic and magnetic structures of Mn(Co,Ge)(2) are reported herein. The system crystallizes in the space group P6(3)/mmc as a superstructure of the MgZn(2)-type structure. The system exhibits two magnetic transitions with associated magnetic structures, a ferromagnetic (FM) structure around room temperature, and an incommensurate structure at lower temperatures. The FM structure, occurring between 193 and 329 K, is found to be a member of the magnetic space group P6(3)/mm′c′. The incommensurate structure found below 193 K is helical with propagation vector k = (0 0 0.0483). Crystallographic results are corroborated by magnetic measurements and ab initio calculations.