实验室晶体积分衍射效率标定方法研究

基于X射线衍射仪运行的稳定性和角度的精密控制能力,以平面季戊四醇(PET)晶体为样品,对晶体的积分衍射效率标定方法进行了实验研究。实验的光源是Cu靶X射线管,通过适当选取镍滤片和精细控制管电压,极大地抑制了Kβ线谱和韧致辐射,实现了Kα线能量单色化。正比计数器前端的狭缝是0.05mm,采用0.001°的步进角度对源强和Kα线衍射峰分别进行扫描。数据处理后得出在Cu的Kα线能点(8047.823eV)处,该平面PET晶体的积分衍射效率是(1.759±0.002)×10-4 rad。实验结果表明该方法可以在实验室条件下快速、方便地完成平面晶体积分衍射效率的标定。

Calibration Research of Integral Diffraction Efficiency of Crystal in Laboratory

Based on stability and angle precision control of the X-ray diffractometer, the calibration technique of integral diffraction efficiency of the flat crystal is introduced by taking the flat PET crystal as sample. X-ray source is Cu X-ray tube and it is monochromatic at Cu-Kα lines by choosing appropriate high voltage and nickel foils to attenuate bremsstrahlung and Cu-Kβ lines. The slit width in front of proportional counter is 0.05 mm. The source and diffractive curve are scanned in steps of 0.001°. The data show that the integral diffraction efficiency is (1.759±0.002)×10-4 rad at Cu-Kα (8047.823 eV). The results show that this calibration technique is efficient and it can be completed conveniently in common laboratory.