光子学报, 2012, 41 (9): 1090, 网络出版: 2012-08-31
基于X射线衍射仪的X光晶体本征参量的标定
Calibration of Characteristic Parameters for Xray Plane Crystal on the Automatic Xray Diffractometer
摘要
X光晶体本征参量的实验标定是准确鉴定X光晶体种类和品质,研制各种类型晶体谱仪,X光线谱定量测量和高分辨X光单能成像的基础.基于X射线衍射仪, 通过制作平面晶体样品架,采取控制X射线管电源、滤波片选取和厚度控制等措施, 极大地抑制了CuKβ及韧致辐射, 使X射线管光源CuKα单能化, 提出了用滤片作为光源单能化的判据.对X光线谱测量中常用的X光分光晶体季戊四醇[PET(002)]的晶格常量2d和CuKα能点的积分衍射效率Rc进行了标定方法研究, 其标定值分别为(0.874 25±0.000 42)nm和(1.759±0.024)×10-4 Rad.基于X射线衍射仪的X光晶体本征参量的精密实验标定方法既快速高效, 且十分方便和灵活.通过更换衍射仪的X射线管靶材, 采取类似方法, 可以标定其它能点的晶体积分衍射效率, 可为X光晶体的本征参量库提供更多的标定数据.
Abstract
Xray crystal characteristic parameters are the bases of identification of Xray crystal species and class, kinds of Xray crystal spectrometer fabrication, Xray lines intensity quantitative measurement and Xray monochromatic image diagnosis. On the automatic Xray diffractometer (XRD), based on stability and precision control of θ and 2θ goniometer, special plane crystal holder was made. Bremsstrahlung and CuKα line were attenuated for 5 orders by 40 μmthick Nickel filter, Xray sources was to be CuKα monochromatic source, and transmission power of filter was the criterion of CuKα monochromatic source. For Xray Pentaerythritol(002) plane crystal of Crystal lattice (2d) and integral reflective coefficient (Rc) of CuKα energy were calibrated, there are 2d=(0.87 425±0.00 042)nm, Rc=(1.759±0.024)×10-4 Rad respectively. This kind of experimental method is efficient and convenient on XRD in common laboratory. On XRD, other monochromatic Xray sources can be obtained by changing the material of Xray tube, and integral reflective coefficient of different energy will be obtained by the same way.
杨国洪, 韦敏习, 侯立飞, 易涛, 李军, 刘慎业. 基于X射线衍射仪的X光晶体本征参量的标定[J]. 光子学报, 2012, 41(9): 1090. YANG Guohong, WEI Minxi, HOU Lifei, YI Tao, LI Jun, LIU Shenye. Calibration of Characteristic Parameters for Xray Plane Crystal on the Automatic Xray Diffractometer[J]. ACTA PHOTONICA SINICA, 2012, 41(9): 1090.