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

The atomic and magnetic structures of Mn(Co,Ge) are reported herein. The system crystallizes in the space group 6/ as a superstructure of the MgZn-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 6/''. The incommensurate structure found below 193 K is helical with propagation vector = (0 0 0.0483). Crystallographic results are corroborated by magnetic measurements and ab initio calculations.