【摘 要】
：
Na0.5(Bi3/4RE1/4)0.5TiO3 (RENBT,RE =Nd,Gd,Dy,and Ho) compounds were investigated in the framework of first-principles calculations using the full potential linearized augmented plane wave (FP-LAPW)method based on the spin-polarized density functional theo
【机 构】
：
Laboratory of Physics of Condensed Matter (LPMC),University of Picardie Jules Verne,Scientific Pole,
论文部分内容阅读
Na0.5(Bi3/4RE1/4)0.5TiO3 (RENBT,RE =Nd,Gd,Dy,and Ho) compounds were investigated in the framework of first-principles calculations using the full potential linearized augmented plane wave (FP-LAPW)method based on the spin-polarized density functional theory implemented in the WIEN2k code.Combined charge density distribution and Ti K-edge X-ray absorption spectra reveal that the RENBT compositions with high polarization values are accompanied by a higher TiO6 distortion,DyNBT,and NdNBT compounds.The effect of the rare-earth elements on the polarization is confirmed experimen-tally with the collection of the hysteresis loops.The investigation of the electronic properties of the compounds highlights the emergence of a magnetization owing to the 4f orbital effect of the rare-earth elements.Besides,the investigation of the chemical ordering shows a short-range chemical ordering for the pure composition and an increased A-site disorder for dysprosium doped NBT system.The increased disorder may speak for increased relaxor properties in the RE doped compositions.
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