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Polar and non-polar atomic motions in the relaxor ferroelectric PLZT from dielectric, anelastic and NMR relaxation

F. Cordero·M. Corti·F. Craciun·C. Galassi·D. Piazza·F. Tabak
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Abstract

Dielectric, anelastic and ^139La NMR relaxation measurements have been made on the relaxor ferroelectric Pb(1-3x/2)La(x)Zr(0.2)Ti(0.8)O(3) (PLZT) with x = 0.22. The dielectric susceptibility exihibits the frequency dispersive maximum due to the freezing of the polar degrees of freedom around T ~250 K. The anelastic and especially NMR relaxation, besides this maximum, indicate an intense and broad component at lower temperatures, attributed to rotational modes of the O octahedra, weakly coupled to the polar modes. It is discussed why such short range rotational instabilities, known to occur in the Zr-rich rhombohedral region of the PLZT phase diagram, might appear also in the Ti-rich region.

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F. Cordero, M. Corti, F. Craciun, C. Galassi, D. Piazza, F. Tabak. 2004-11-05. Polar and non-polar atomic motions in the relaxor ferroelectric PLZT from dielectric, anelastic and NMR relaxation. https://doi.org/10.1103/physrevb.71.094112

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