MAGNETIC AND OPTICAL PROPERTIES OF TRANSPARENT RbNiF3

Abstract
Magnetic and optical data on single‐crystal RbNiF3 are presented. We conclude that this material is ferrimagnetic, rather than antiferromagnetic as previously reported, with a transition temperature of 139°K and a saturation moment of 21 emu/g at 4.2°K. The basal plane is the preferred plane and the out‐of‐plane anisotropy is 106 ergs/cc. The Faraday rotation measured along the c axis at 77°K and 80% of magnetic saturation exhibits a peak value of 400° per cm at a wavelength of 4950 Å and values of 250° to 50° per cm in the region 5000 to 6000 Å where the optical absorption is lowest.