2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/26475We suggest considering the Burns temperature in lead containing relaxor ferroelectrics as the temperature, at which Pb becomes off-center and nearly randomly occupies positions around the center on a sphere with the radius, which increases with the temperature decrease. The significance of the Burns temperature, in this approach, is the crossover between the soft-mode and order-disorder dynamics. The lattice parameter, birefringence and neutron scattering experiments are analyzed in the light of this model.Report at IMF 2005, BrazilDisordered Systems and Neural Networkstext