Magnetic characteristics of GdAl4 in a predictive scheme for the strength of magnetic exchange in compounds based on rare earths

The spatially confined and magnetically active 4f electrons are considered to order magnetically as a result of indirect interactions via the conduction electrons. This results in oscillatory variations in the sign and strength of the exchange interaction as a function of electron concentration (EC) and interatomic distances. In this study the author reports on the magnetic properties of the last of the compounds in the system Gd-Al for which no magnetic data have previously been reported, namely GdAl4, and its ordering temperature compared with the ordering temperatures of other compounds in systems based on Gd with Ni, Cu, Zn, Al and Si. The graphical representation demonstrates the oscillatory nature of indirect exchange as a function of EC and radius. (Auth.)