Magnetocaloric effect in GdCu intermetallic compound

A single crystal of GdCu of FeB‐type was grown by the Czochralski method from a levitating melt and characterized using X‐ray diffraction, dc ‐magnetization M(T) and ac ‐magnetic susceptibility (ac‐ χ ). From ac and dc magnetic susceptibility a transition to the antiferromagnetic state has been found below T N = 37 K. The paramagnetic Curie temperature θ p and the effective magnetic moment μ eff were estimated assuming the Curie‐Weiss law in the 100 to 300 K range and were found to be θ p = –37 K and μ eff = 8.5 μ B . The last value is enhanced relatively to the free ion value of 7.94 μ B for Gd 3+ . The calculated entropy changes Δ S m for the examined compound amount to −1.22 J/K·kg, –0.6 J/K·kg and –0.09 J/K·kg at 7, 5 and 2 T respectively. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)