Abstract
The introduction of structural disorder into perovskite ferroelectrics leads to the observation of diffuse phase transition behavior. In this paper, the microstructural characteristics and phase transition behavior of lanthanum-modified lead titanate are discussed. It is shown that the diffuse nature of the transition is connected with the appearance of ferroelectric domain structures exhibiting texture on the mesoscopic (≈ 10 run) length scale. The theoretical implications of these results are briefly discussed.