Investigation of the electronic structure and photoluminescence properties of Eu^(3+) in Sr_2 Mg_(1-x)Zn_xSi_2O_7 (0≤x≤1)  

作　　者：ZHANG ZhiYa WANG YuHua 

机构地区：[1]Key Laboratory for Magnetism and Magnetic Materials of the Ministry of Education,Department of Materials Science,School of Physical Science and Technology,Lanzhou University,Lanzhou 730000,China

出　　处：《Chinese Science Bulletin》2012年第8期935-940,共6页

基　　金：supported by the Youth Innovation Research Fund for Interdisciplince of Lanzhou University (LZUJC200906);the National Natural Science Foundation of China (50925206)

摘　　要：Undoped and Eu 3+-doped Sr 2 Mg 1-x Zn x Si 2 O 7 (0≤x≤1) powder crystals were obtained by conventional solid-state reaction.X-ray diffraction,inductively coupled plasma analysis,and Fourier transform infrared spectroscopy results implied that a complete solid-solution formed between Sr 2 MgSi 2 O 7 and Sr 2 ZnSi 2 O 7 as well as local structural adjustment.Excitation spectra exhibited O 2-Eu 3+ charge transfer (CT) bands centered at 250 nm for Sr 2 MgSi 2 O 7:Eu 3+ and 258 nm for Sr 2 ZnSi 2 O 7:Eu 3+.Emission spectra exhibited a major band around 616 nm,which showed the environment around Eu 3+ was non-centrosymmetric in both Sr 2 MgSi 2 O 7:Eu 3+ and Sr 2 ZnSi 2 O 7:Eu 3+.In addition,first principles calculations within the local density approximation (LDA) of density functional theory (DFT) were used to calculate the electronic structure of Sr 2 MgSi 2 O 7 and Sr 2 ZnSi 2 O 7.Calculated results were correlated with experimental UV-vis reflection spectra and the observed shift of the O 2-Eu 3+ CT band.Undoped and Eu3＋doped Sr2Mg〉xZnxSi207 （0〈x 〈 1） powder crystals were obtained by conventional solidstate reaction. Xray diffraction, inductively coupled plasma analysis, and Fourier transform infrared spectroscopy results implied that a complete sol idsolution formed between Sr2MgSi207 and Sr2ZnSi207 as well as local structural adjustment. Excitation spectra exhibited O2Eu3＋ charge transfer （CT） bands centered at 250 nm for Sr2MgSi2OT：EU3＋ and 258 nm for Sr2ZnSi2OT：Eu3＋. Emission spectra exhibited a major band around 616 nm, which showed the environment around Eu3＋ was noncentrosymmetric in both Sr2MgSi207：Eu3＋ and Sr2ZnSi2OT：EU3＋. In addition, first principles calculations within the local density approximation （LDA） of density functional theory （DFT） were used to calculate the electronic structure of Sr2MgSi207 and Sr2ZnSi2OT. Calculated results were correlated with experimental UVvis reflection spectra and the observed shift of the O2Eu3＋ CT band.

关 键 词：电子结构 光致发光特性 傅里叶变换红外光谱 密度泛函理论 局域密度近似 计算结果 铕 X射线衍射 

分 类 号：O613.71[理学—无机化学] O484.41[理学—化学]