Magnetic and optical properties of cobalt-substituted RbNiF₃

When nickel is replaced by cobalt in RbNi 1Single Bond signxCoxF3, the hexagonal structure and the ferrimagnetic order are maintained; however, the easy axis of magnetization at 77°K rotates in a complex manner from perpendicular (x <. 07) to parallel to the optic axis (x >. 17). In the optical window region at 17,000 cm-1 the bulk absorption remains constant at 5 cm-1 and the Faraday rotation increases to 200 deg/cm at x =. 25. © 1968 The American Institute of Physics.