摘要
A more precise expression for the angular deviation from the Bragg law and the angularrange of X-ray diffracted by perfect crystal are derived. The critical angle of the total re-flection of X-ray from the surface of crystal is obtained naturally by the new expressions,which well coincides with that deduced in optics in consideration of the refraction. Twopeaks appear on the rocking curve when X-rays shoot at the surface at a small glancing angleand simultaneously on the side of crystal although the double-crystal is in (n, -n) setting,which is called the "edge effect". The angle between these two peaks on the rocking curvecan be used to measure the number of electrons in an unit cell of crystal.
A more precise expression for the angular deviation from the Bragg law and the angularrange of X-ray diffracted by perfect crystal are derived. The critical angle of the total re-flection of X-ray from the surface of crystal is obtained naturally by the new expressions,which well coincides with that deduced in optics in consideration of the refraction. Twopeaks appear on the rocking curve when X-rays shoot at the surface at a small glancing angleand simultaneously on the side of crystal although the double-crystal is in (n, -n) setting,which is called the 'edge effect'. The angle between these two peaks on the rocking curvecan be used to measure the number of electrons in an unit cell of crystal.
基金
Project supported by the National Natural Science Foundation of China.
