Study of the microscopic structures in 0.72Pb([Mg.sub.1/3][Nb.sub.2/3])[O.sub.3]-0.28PbTi[O.sub.3] relaxor ferroelectrics by means of x-ray diffraction

Various x-ray diffraction experiments are employed to study the microscopic-scale structures of 0.72Pb([Mg.sub.1/3][Nb.sub.2/3])[O.sub.3]-0.28PbTi[O.sub.3] relaxor ferroelectrics in a high external dc field during phase transition. The results clearly prove that a change in the temperature also leads to a major change in the dominating cluster's orientation, as well as their interaction direction.