二元系SrTiO_3-CaTiO_3固溶体的XRD研究(英文)

XRD Study of the Solid Solution of SrTiO_3-CaTiO_3 Binary System

进行了SrTiO3_CaTiO3系统的X_射线衍射分析 ,结果表明 ,当Ca2 +置换Sr2 +而形成ABO3钙钛矿型固溶体时 ,相对衍射强度 (I/I1) 10 0 减弱 .通过测定晶体结构的晶胞参数 ,进而比较衍射强度理论值及实测值 ,可以证明 (I/I1) 10 0 的减弱与ABO3钙钛矿型结构中A位离子的原子散射因子有关 ,由于钙的原子散射因子小于锶的原子散射因子 ,导致 (Sr ,Ca)TiO3固溶体的相对衍射强度 (I/I1) 10 0 减弱 .另外 ,通过比较衍射强度I110 /I111的实测值与计算值 ,还获得了A位离子的占位情况 .

The XRD (X_Ray Diffraction) analysis of SrTiO 3_CaTiO 3 system was carried on, the results showed that a solid solution with the ABO 3 perovskite type structure was formed when Ca 2+ replaced Sr 2+ ions, and the relative intensity of the X_ray diffraction ( I/I 1) 100 decreased. The cause of which was found by the comparison between theoretical and measured diffraction intensities by determining the lattice parameter of sample structures. The change of ( I/I 1) 100 depends on the atomic scattering factor of ions in Site A in the structure. The ( I/I 1) 100 decreases in (Sr,Ca)TiO 3 solid solution because the atomic scattering factor of calcium is less than that of strontium. The space occupancy of ions in Site A can be obtained by comparing the intensity I 110 /I 111 measured and calculated. This approachprovides the basis for the microscale phase identification and microstructure analysis of ceramic mate_ rials based on SrTiO 3.