R. Lobos, R. L. Moreira, N. Mohallem
Aug 1, 1992
Abstract In this work we have explained the diffuse phase transitions (PT) of sol-gel grown Barium Titanate samples through a model where weighted sums of “normal” PT from micro-regions of the material are performed. Using Landau-Devonshire's expressions for ferroelectric transitions, we obtain the smeared macroscopic behaviour of the PT. The results are used to show why deviations from Curie-Weiss, and also Smolensky-Isupov, behaviours of the dielectric permittivity are very often found in ferroelectric relaxors.