Magnetic properties of the Ce2Fe17−xMnx helical magnets up to high magnetic fields

Magnetic properties of the Ce2Fe17-xMnx, x=0-2, alloys in magnetic fields up to 40T are reported. The compounds with x=0.5-1 are helical antiferromagnets and those with 1 < x2 are helical ferromagnets or helical antiferromagnets at low and high T, respectively. Mn ions in the system carry average magnetic moment of 3.0+/-0.2muB that couple antiparallelly to the Fe moments. Easy-plane magnetic anisotropy in the Ce2Fe17-xMnx compounds weakens upon substitution of Mn for Fe. The absolute value of the first anisotropy constant in the Ce2Fe17-xMnx helical ferromagnets decreases slower with increasing temperature than that calculated from the third power of the spontaneous magnetization. Noticeable magnetic hysteresis in the Ce2Fe17-xMnx, x=0.5-2, helical magnets over the whole range of magnetic fields reflects mainly irreversible deformation of the helical magnetic structure during the magnetization of the compounds. A contribution from short-range order (SRO) magnetic clusters to the magnetic hysteresis of the helical magnets has been also estimated.