Application of Moments to Light Scattering in Antiferromagnets

Measurements on two-spin fluctuation light scattering in MnF₂ have been obtained over the temperature range 2-300°K the results are in good agreement with a theoretical analysis based on frequency moments and intensity of the scattering spectra. We find that the first moment shows critical-type behavior in the vicinity of the Néel temperature T_N and that the measured high-temperature second moment allows a determination of the antiferromagnetic exchange constant in the paramagnetic phase.