Magnetization of Solid Solutions of Antiferromagnets Ni3 – xCoxB2O6 with the Competing Orientation of Anisotropy Axes

We studied the magnetic properties of Ni3 – xCoxB2O6 solid solutions with the kotoite structure, where x = 0; 0.19; 0.6; 0.93; 2. The compounds Ni3B2O6 and Co3B2O6 are antiferromagnets, with their easy axis of magnetization coinciding with the crystallographic directions c and b, respectively. In the Ni2.81Co0.19B2O6 solid solution, two features are found on magnetization curves, while in other solid solutions there is only one feature. With the cobalt ion concentration x > 0.9, the magnetic moments are predominantly oriented along the b axis.