Ca_3NbGa_3Si_2O_(14)晶体的拉曼散射及密度泛函研究  

Raman Scattering and DFT Investigation of CNGS Crystal

作　　者：赵朋[1] 夏海瑞[2] 冉栋刚[2] 凌宗成[2] 周城[1] 王培吉[1] 张仲[1] 石绪忠[3] 袁多荣[3] 

机构地区：[1]济南大学理学院,济南250022 [2]山东大学物理与微电子学院,济南250100 [3]山东大学晶体材料国家重点实验室,济南250100

出　　处：《人工晶体学报》2006年第3期604-607,593,共5页Journal of Synthetic Crystals

基　　金：国家自然科学基金(No.10274043);济南大学校基金(No.Y0512);山东大学晶体材料国家实验室开放课题

摘　　要：根据空间群理论(SPT)计算了Ca3NbGa3S i2O14晶体(简称CNGS)的拉曼光谱,并测量了CNGS的室温拉曼光谱。根据晶体结构,构造了两个团簇(Ca3NbGa2S iO12,Ca3NbGaS i2O12),利用密度泛函理论(DFT)对拉曼光谱进行了计算和模拟。结果表明理论与实验非常吻合,CNGS良好的压电性起源于两个团簇大的极化率各向异性。Raman spectra of Ca3NbGa3Si2O14 （CNGS） crystal were calculated based on the space group theory （SPT） and measured under the room temperature. Two clusters （Ca3NbGa2SiO12 and Ca3NbGaSi2O12） were constructed according to the structure of CNGS crystal. The density-functional theory （DFT） calculations were made on the two clusters to model the Raman spectra. An excellent agreement has been achieved between Raman spectra calculated by the SPT theory, DFT theory and those observed in the experiments. The excellent piezoelectric properties of CNGS are mainly attributed to the large polarizability anisotropy of Ca3 NbGa2 SiO12 and Ca3 NbGaSi2 O12 clusters.

关 键 词：CNGS晶体 拉曼光谱 空间群 密度泛函理论 

分 类 号：O734[理学—晶体学]