Magnetization Process in the Mixed System of Uniaxial and Planar Antiferromagnets Ni_xCo_1−xCl₂·6H₂O in High Magnetic Field

Abstract

The magnetization processes of Ni_xCo_1−xCl₂·6H₂O have been studied in the external field up to 20 T in the temperature range from 4.2 to 1.3 K. The magnetization processes for the systems with 0<x<0.45 and with 0.75<x<1 are essentially similar to those for CoCl₂·6H₂O and for NiCl₂·6H₂O, respectively. The effective anisotropy η=H_A⁄H_E decreases toward zero as x approaches to some intermediate concentration. The features of the magnetization processes in the range 0.5<x<0.7 are quite different from those of usual antiferromagnet indicating some of characteristics of a random mixture of uniaxial and planer antiferromagnets.