铅基复合钙钛矿型材料的电子结构和介电性能

Electronic Structure and Dielectric Property of Lead-base Materials with Complex Perovskite Structure

采用CASTEP软件对不同B位取代的Pb(BⅠBⅡ)O3材料的电子结构进行计算,从离子价键、电子态密度等方面研究了铅基复合钙钛矿型材料介电性能差别巨大的原因。结果表明:在较大B位离子撑起晶体结构的前提下,较小B位离子的d轨道和O-2p轨道的相互作用是影响弛豫铁电体介电常数的主要因素;计算结果与文献的实验结果一致。说明介电性质与晶体的电子结构直接相关,为进一步从电子结构出发研究此类材料的介电理论模型提供了参考。

The electronic structure of Pb（B^ⅠB^Ⅱ）O3 with different B ions was investigated using CASTEP method,the strength of ionic bonds and the density of states were studied in detail for exploring the great differences between dielectric properties of Pb（B^ⅠB^Ⅱ）O3.The results show that,when the greater B ions and O ions form the frame of the lattice structure,the dielectric constants are significantly impacted by the interaction between the two orbits O-2p-orbit and the d-orbit of the lesser B ions.And the results are consistent with the experiment data available in the literature.It indicates that there are close ties between the electronic structure and dielectric property of complex perovskite structure materials.And the result will be a reference for the further research of the dielectric theory.