STUDY OF THE MAGNETIC PROPERTIES OF THE RARE EARTH METAL-INDIUM SYSTEM AT HIGH TEMPERATURES

Abstract

The Faraday method was used to study for the first time the temperature dependence of the magnetic susceptibility [????(????)] of rare earth metals (REM = Gd, Tb, Dy, Ho, Er, Tm) and their compounds with In in a wide temperature range of 20-1700 0C, covering the solid state, the melting process and the liquid state of these compounds. It was found that for all studied compounds, the ? (?) dependence, with the exception of compounds of the Gd-In system, obeys a linear law, and for compounds of the Gd-In system, the modified Curie-Weiss law, both in the solid and in the liquid states. The paramagnetic Curie temperature ????????, the CurieWeiss constant C, the temperature-independent component of the susceptibility ????0, and the effective numbers of magnetic moments ??????? per REM atom were calculated from the ???? ?1 (?) (T) dependence of the compounds. It is shown that the paramagnetic states of the studied samples are satisfactorily described by the Van Vleck theory of paramagnetism. For the first time, the prediction of the theory of exchange interactions of the Ruderman-Kittel-KasuyaYosida type (RKKI) on the existence of a direct proportional dependence of the experimental values of ???????? on the de Gennes factor for the equiatomic compounds under study, similar to that of pure TREM, was confirmed semi-empirically. On the whole, it has been established that for the compounds of TREM with in, as in pure TREM, an exchange interaction of the RKKY type is characteristic.