Dielectric and Raman studies of (BaxPb1−x)(Yb0.5Nb0.5)O3

TLDR: In this article, Raman spectra of the solid solution series (BaxPb1−x)(Yb0.5Nb 0.5)O3 from x = 0.0 to 0.3 have been analyzed and a new mode at 420 cm−1 is observed for the compounds with Ba2+ substitution.

Abstract: Dielectric dispersion and Raman studies are carried out on the solid solution series (BaxPb1−x)(Yb0.5Nb0.5)O3 from x = 0.0 to 0.3. The x-ray diffraction analysis indicates that with the substitution of Ba2+, the intensity of the peaks corresponding to antiparallel displacement of Pb2+ decreases and the structure becomes cubic. The low frequency dielectric dispersion studies indicate that the series undergoes a transition from an antiferroelectric to a relaxor ferroelectric with variation of x. Raman spectra of the compositions indicate the presence of a greater number of modes for the compounds with cubic structure (). A new mode at 420 cm−1 is observed for the compounds with Ba2+ substitution. The intensity of this mode increases monotonically with increase in Ba2+ substitution and this has been attributed to the commencement of local distortion. This could be responsible for the appearance and increase in the diffuseness around Tmax, the temperature corresponding to .