Grain boundary bondings in ceramics by spatially resolved EELS

通过空间分辨 EELS 研究陶瓷中的晶界键合

• 批准号: 10450243
• 负责人: TANAKA Isao
• 金额: $ 7.36万
• 依托单位: KYOTO UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 1998
• 资助国家: 日本
• 起止时间: 1998 至 1999
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-10450243/
• 关键词: EELS; ELNES; electron microscopy; MgO; SiィイD23ィエD2N4; DV-Xalpha method; lattice statics; DV-Xα法; MgO; シリコン不純物

Impurities adsorbed at the grain boundary play central roles in determining macroscopic properties that can not be expected in single crystal materials.The presence of impurities has been assumed in many kinds of ceramics.However, quantitative information on these impurities as well as their bonding states has not been clarified before the recent progress of high resolution electron microscopy coupled with sub-nano meter resolution electron energy loss spectroscopy(EELS).In the present study, we investigated chemical states of Si in MgO as an example. O-K edge, Si-LィイD223ィエD2 edge, Mg-LィイD223ィエD2 edge ELNES (electron energy loss near edge structure) were measured and compared with theoretical results obtained by our calculations using first principles molecular orbital method.Model clusters composed of approximately 100 atoms were used for the calculation.As a result, presence of six-fold coordinated Si atoms in the MgO matrix can be recognized.

杂质吸附在晶界中在确定单晶材料中无法预期的宏观特性中起着核心作用。杂质的存在已在多种陶瓷中被假定。光谱法（鳗鱼）。在本研究中，我们以MGO中的Si化学状态为例。 O-K edge, Si-LII D223E D2 edge, Mg-LII D223E D2 edge ELNES (electron energy loss near edge structure) were measured and compared with theoretical results obtained by our calculations using first principles molecular orbital method.Model clusters composed of approximately 100 atoms were used for the calculation.As a result, presence of six-fold coordinated Si atoms in the MgO matrix can be认可。

项目成果

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I. Tanaka: "First principles calculations of ELNES/NEXAFS of BN polytypes using model clusters."Phys. Rev. B. 60. 4944-4951 (1999)

I. Tanaka：“使用模型簇对 BN 多型体进行 ELNES/NEXAFS 的第一原理计算。”Phys。

I. Tanaka: "Core-hole effects on theoretical ELNES/NEXAFS of MgO."Phys. Rev. B.. 61. 2180-2187 (2000)

I. Tanaka：“芯孔对 MgO 理论 ELNES/NEXAFS 的影响。”Phys。

M.Mizuno: "Chemical Bonding of the Fe/TiX(X=C,N,or O) Interfaces" Acta.Mater.46. 1637-1645 (1998)

M.Mizuno：“Fe/TiX(X=C、N 或 O) 界面的化学键合”Acta.Mater.46。

I. Tanaka: "Theoretical calculation of oxygen K electron-energy-loss near-edge structures of Si-doped MgO."J. Phys. Cond. Matter.. 11. 5661-5670 (1999)

I. Tanaka：“Si掺杂MgO氧K电子能量损失近边缘结构的理论计算”。