Investigation of the electronic structure and photoluminescence properties of Eu~(3+) in Sr_2 Mg_(1-

• 出 处: Chinese Science Bulletin
• 发表日期: 2012年08期
• 关键词: adjustment inductively bands centered Figure Tianjin covalent octahedral spectro

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 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 is formed between Sr 2 MgSi 2 O 7 and Sr 2 ZnSi 2 O 7 as well as local structural adjustment. Excitation spectra demonstrated O 2-Eu 3+ charge transfer (CT) 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 o f the O 2-Eu 3+ CT band.