Critical behavior of a single-crystal (110) Cr near the Neel temperature

Using the Sn-119 Mossbauer effect, the critical magnetic behavior of a sing le-crystal (110) Cr sample doped with similar to 0.1 at% Sn-119 was investi gated in the vicinity of the Neel temperature, T-N. The transition from a p aramagnetic to an antiferromagnetic: state was found to have a double chara cter: it is continuous and has a hysteresis of DeltaT(N) approximate to 1.3 K. The latter feature has been observed for the first time. The critical e xponent beta of the average hf field was found to be a continuous function of the reduced temperature, t, ranging between beta approximate to 0.3 for t approximate to 10(-3) and beta approximate to 0.57 for t approximate to x 10(-2).