Isomorphic substitution in the system Pb<sub>(8-х)</sub>Gd <sub>х </sub>Na<sub>2</sub>(VO <sub>4</sub>)<sub>6</sub>O<sub>(х/2) </sub>
Keywords:
lead-sodium oksovanadate, gadolinium, X-ray powder diffraction, apatite, Rietveld method solid solutions, conductivityAbstract
Solid solutions Pb<sub>(8-х)</sub>Gd <sub>х </sub>Na<sub>2</sub>(VO <sub>4</sub>)<sub>6</sub>O<sub>(х/2) </sub> have been investigated by X-ray powder diffraction, scanning electron microscopy and conductivity measurement methods. The crystal structure of solid solutions was refined by Rietveld method. It was established that substitution of lead for gadolinium occurs in the region up to x = 0.15. Dependence of a substitution degree on conductivity has been studied. The character of conductivity changing shows that the cationic conductivity is changed to the anionic one with raising of gadolinium content in the solid solution.References
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