Comparative studies of magnetic circular dichroism and susceptibility in antiferromagnetic Rb2NiF4

Abstract
The authors studied the magnetic susceptibility of the two- dimensional antiferromagnet Rb2NiF4 in the temperature range 77-671 K. The values of the paramagnetic Neel temperature, the Van Vleck susceptibility and exchange integral were calculated from the analysis of the susceptibility measurements and were found to be close in magnitude to and consistent with those reported for the iso-structural K2NiF4. The optical absorption and magnetic circular dichroism (MCD) spectra for the 3A2 to 1T2, 3T1b transitions were measured in the range 50-295 K and the zeroth, first and second moments of MCD were estimated.