Magnetic and transport properties of Mn2FeAl

Experimental studies of polycrystalline Mn2FeAl revealed that it crystallizes in a primitive cubic structure of beta-Mn type (space group P4(1)32) and is an antiferromagnet with Neel temperature T-N = 40 K. The alloy exhibits temperature dependence of transport properties typical for semiconductors and has abnormally high electrical resistivity (rho similar to 238 mu Omega.cm at room temperature). High Curie-Weiss temperature Theta(CW) similar to -905 K and a large value of the frustration parameter f approximate to 23 points to a strong frustration of the magnetic subsystem. These experimental findings are in contrast with reported results of first-principles calculations which predicted Mn2FeAl to be half metallic ferrimagnet crystallizing in the Heusler crystal structure.