Magnetic Susceptibility and Electrical Resistivity of Uranium Phosphides and UP-ThP Solid Solutions

Abstract

The magnetic susceptibility and electrical resistivity of uranium phosphides and UP-ThP solid solutions were measured. All the uranium phosphides exhibited paramagnetism at room temperature, and followed the Curie-Weiss law. The Néel point T^N for UP² and UP, and the Weiss constant θ were estimated. Ferromagnetic components made their appearance in UP² and UP, in the temperature range below T^N. With UP-ThP solid solutions, the changes according to composition observed in the values of T^N and θ indicated that UP is magnetically diluted by ThP, which latter compound is characterized by Pauli paramagnetism, and whose presence contributes to diminish the exchange interactions. The electrical resistivity of UP increased rather rapidly with temperature up to a point corresponding to T^N beyond which the tendency changed sharply to a slightly negative coefficient. ThP showed a consistently low value of resistivity, were slowly rising with temperature, and that of UP-ThP solid solutions revealed a behavior intermediate between those of UP and ThP.