Structural and magnetic properties of MnAs 0.90P 0.10

Abstract

MnAs 0.90P 0.10 takes the orthorhombic MnP type structure at temperatures below the second-order transition temperature T D = 449 ± 2 K, and the hexagonal NiAs type structure between T D and the melting point T m = 1189 ± 10 K. The structural changes, in positional parameters and unit cell dimensions (as well as interatomic distances), have been determined for the increasing distortion at temperatures below T D by means of powder X-ray and neutron diffraction. At low temperatures two distinct incommensurate magnetic structures are found, respectively, over the temperature intervals 0 < T < T S1 = 105 ± 5 K and T S2 = 185 ± 5 < T < T N = 237 ± 5 K, whereas a ferromagnetic spin arrangement prevails over the intermediate temperature range T S1 < T < T S2.