Acute and obtuse rhombohedrons in the local structures of relaxor ferroelectric Pb(MgNb)O

Hu, W.*; 林 好一*; 大和田 謙二; Chen, J.*; 八方 直久*; 細川 伸也*; 高橋 正光; Bokov, A.*; Ye, Z.-G*

Physical Review B, 89(14), p.140103_1 - 140103_5, 2014/04

https://doi.org/10.1103/PhysRevB.89.140103

The local structures around Nb and Pb in the relaxor ferroelectric Pb(MgNb)O were investigated by X-ray fluorescence holography. The Pb atomic images around Nb showed a rhombohedral distortion of the crystal unit cells. The Pb-Pb correlated images showed a local structure of body-center-like superlattice, proving a rigid three-dimensional network structural model combining the two kinds of rhombohedrons. This superstructure and the fluctuating Pb and Nb atoms play an important role in the relaxor behavior of this material.