First order antiferromagnetic transition in europium

Abstract The antiferromagnetic first order transition in europium has been studied with calorimetric and low field ac susceptibility measurements. At T N (89.1 K) a latent heat of (61 ±2) J mol −1 was obtained. The dispersive component of the susceptibility undergoes a discontinuous change at T N while no effects were observed in the loss part. The latent heat, which is exceptionally high to be caused by a magnetic phase transition, can be fully accounted for by a strong tetragonal distortion of the europium lattice at T N recently reported.