Critical magnetic susceptibility of gadolinium.

The magnetic suspectibility of a single crystal of high-purity gadolinium has been measured in the critical region with use of ac susceptibility methods. For reduced temperatures t 10, the data are described by a simple power law of the form Z At "with an exponent y 1.22(2) and a Curie temperature T, 293.51(3) K. For reduced temperatures t +10 3, the data cannot be described by a simple power law and indicate the possibility of a crossover to different critical behavior.