Magnetic Transition Temperatures of the Sm--Gd Alloy System

The magnetic transition temperatures for Sm--Gd alloys with concentrations ranging from 8-97% Gd are presented. Our results show a single magnetic transition for Gd-rich alloys with transition temperatures decreasing as the Sm concentration increases. This trend continues through alloys of intermediate concentration, although the nature of the transition is not clear. For the Sm-rich end of the alloy range, the Sm-type antiferromagnetic transitions are clearly seen. The transition temperatures decrease as the two-thirds power of the de Gennes factor until the atomic concentrations of the two elements become almost equal, at which point a steeper decline is seen. Gd sub 97 Sm sub 3 , Gd sub 8 Sm sub 92 and Gd sub 45 Sm sub 55 are discussed in detail.