Substitution of Praseodymium for Cadmium and Lead in the Structure of Pr5Mo3O16+δ

Abstract

Solid solutions based on fluorite-like phase in systems Pr<inf>5–x</inf>Me<inf>x</inf>Mo<inf>3</inf>O<inf>16+δ</inf>, where Me = Cd, Pb, have been obtained by solid-phase synthesis from metal oxides. The phase content after calcination at 1000°C has been studied by X-ray powder diffraction; the substitution limits and the dependences of the unit cell parameter on the composition of the systems have been determined. The parameters of the crystal structure of solid solutions have been specified by the Rietveld method. The influence of magnesium oxide additives on the sinterability of cadmium-containing solid solutions has been established. Isomorphous substitution of praseodymium by lead and cadmium has been found to result in a decrease in the conductivity value of the samples in the studied systems.