X射线衍射综合性分析实验教学模式设计

Design of the Teaching Model of X-Ray Diffraction Comprehensive Analysis Experiment

  • 摘要: 为提高X射线衍射(XRD)分析应用教学水平,该文设计了一个XRD综合性分析实验。以立方晶体Cu和Cr的XRD图为例,数学推导其布拉菲点阵、晶面指数、晶格参数。以TiO2的XRD图为例,用Jade软件分析其物相组成。用K值法、峰形拟合和Rietveld全谱拟合法对样品进行了物相定量分析。结果表明:相比于峰形拟合法,Rietveld全谱拟合法具有不依赖于RIR值的优点,晶体模型一致而RIR值不同的物相组成的定量分析结果相一致,并能方便获取精确的晶胞参数值。数学推导晶体结构及物相定量计算、软件进行物相定性以及在物相定量分析中不同软件不同方法的比较使用,能有效提高学生的XRD理论与实践水平。

     

    Abstract: In order to improve the teaching level of X-ray diffraction (XRD) analysis application, a XRD comprehensive analysis experiment is designed. Taking the XRD pattern of cubic crystals Cu and Cr as an example, the Bravais lattice, index of crystal face and lattice parameters are derived mathematically. Taking the XRD pattern of TiO2 as an example, its phase compositions are analyzed by Jade software. The quantitative analysis of phase is obtained by K-value method, peak fitting and Rietveld whole pattern fitting. The results show that Rietveld whole pattern fitting has the advantages of being independent of RIR value compared with peak fitting; the quantitative analysis results of phase composition with the same crystal model and different RIR value are consistent; it is convenient to obtain accurate crystal cell parameter values. Mathematical derivation of crystal structure and quantitative calculation of phase, qualitative analysis of phase by software and comparative use of different software and different methods in quantitative analysis of phase can effectively improve students’ XRD theory and practice level.

     

/

返回文章
返回