Electrical Resistivity and Paramagnetic Resonance in Gadolinium Hexaboride

Magnetic susceptibility measurements on GdB6 have been interpreted in terms of an antiferromagnetic interaction between 4f7 ion cores via one conduction electron per gadolinium atom. Electrical resistivity data are presented which show the spin-disorder contribution to be expected on this basis, and a surprisingly large effect ascribed to short-range order above the Neel temperature. An electron spin resonance has also been observed; this has the characteristics to be expected of a 4f7 ion in a metallic matrix and cannot be observed in the antiferromagnetic temperature range.