Unique features of the crystal structure of the (PbMg1/3Nb2/3O3)0.6-(PbTiO3)0.4 solid solution

An x-ray diffraction study of the paraphase of the (PbMg_1/3Nb_2/3O₃)_0.6-(PbTiO₃)_0.4 solid solution has been found to exhibit a clearly pronounced ferroelectric transition. It is shown that Pb²⁺ ions occupy a special position (000), as opposed to pure PMN and other relaxor ferroelectrics, where they are displaced from it in random directions. The absence of these displacements indicates suppression of frozen-in random electric fields in this compound. Fiz. Tverd. Tela (St. Petersburg) 41, 1282–1285 (July 1999)