Modeling the Dielectric Response and Relaxation Spectra of Relaxor Ferroelectrics
A multi-Debye relaxation model that is based upon the Boltzmann superposition principle has been used to determine the frequency-dispersion behavior of Pb(Mg1/3-Nb2/3)O3 (PMN) and Pb0.88La0.08(Zr0.65Ti0.35)O3 (PLZT 8/65/35) relaxor ferroelectrics. For PMN, relaxation times on the order of seconds contribute to the dispersive character of the dielectric properties. A defect-relaxation mechanism that involves Mg cation hopping in a structure that is composed of interpenetrating 〈111〉 chains of ordered Pb(Mg1/2Nb1/2)O3 is proposed for PMN. Motion of the Mg cations results in destruction and reconstruction of these ordered chains, which contributes to the dispersive character of PMN.
H. Lin et al., "Modeling the Dielectric Response and Relaxation Spectra of Relaxor Ferroelectrics," Journal of the American Ceramic Society, American Ceramic Society, Oct 1999.
Materials Science and Engineering
Keywords and Phrases
Dielectric Relaxation; Lead Compounds; Magnesium; Mathematical Models
Article - Journal
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