Magnetic susceptibility of antiferromagnetic chromium

The static magnetic susceptibility of pure chromium $\chi \mathrm{}\left(T\right)\mathrm{}$ has been measured over the temperature range from 4.3 to 340 K. The experimental results are compared with a theory based on the Fedders-Martin model of an antiferromagnet generalized to include bands of arbitrary shape. Fair agreement between theory and experiment is found for $\chi \mathrm{}\left(T\right)\mathrm{}$ from the Néel temperature ∼ 312 K down to about 130 K. At 90 K the actual susceptibility passes through a minimum, then rises again with decreasing temperature. Neither the minimum nor the observed increase at low temperature are predicted by the theoretical model.