Crystal structure and magnetic properties of pseudobinary solid solutions Pr(In1 − x Pb x )3

Abstract

Structure and magnetic properties of Pr(In1 − x Pb x )3 alloys have been studied in some detail. It has been shown that, in this system, in the whole range of compositions (0 ≤ x ≤ 1), there is a continuous series of disordered solid solutions with a structure of the Cu3Au type. The lattice parameter of these solid solutions varies linearly (according to Vegard’s law). The temperature dependence of the magnetic susceptibility has been studied in the temperature range of 2–300 K. At enhanced temperatures, it is described well by the Curie-Weiss law for all alloys. At low temperatures, an anomalous deviation from this law for the terminal alloys is observed, which is especially strong for PrIn3. In pseudobinary alloys, this anomaly weakens and the magnetic susceptibility itself increases. In the concentration dependence of the susceptibility measured at 2 K, a maximum is observed. The specific features of the dependence of the magnetic susceptibility of pseudobinary alloys on the temperature and concentration x have been explained by a decrease in the local symmetry of crystal field at the sites of Pr3+ ions due to the partial random replacement of their nearest neighbors by atoms of different valences.