X-ray diffracted intensity for double-reflection channel-cut Ge monochromators at extremely asymmetric diffraction conditions
Authors | |
---|---|
Year of publication | 2011 |
Type | Article in Periodical |
Magazine / Source | Journal of Applied Crystallography |
MU Faculty or unit | |
Citation | |
Web | http://scripts.iucr.org/cgi-bin/paper?S0021889811001439 |
Doi | http://dx.doi.org/10.1107/S0021889811001439 |
Field | Solid matter physics and magnetism |
Keywords | X-ray diffraction; X-ray optics; Monochromators |
Description | The width and integrated intensity of the 220 X-ray double-diffraction profile and the shift of the Bragg condition due to refraction have been measured in a channel-cut Ge crystal in an angular range near the critical angle of total external reflection. The Bragg angle and incidence condition were varied by changing the X-ray energy. In agreement with the extended dynamical theory of X-ray diffraction, the integrated intensity of the double diffraction remained almost constant, even for the grazing-incidence condition very close to the critical angle for total external reflection. A broadening of the diffraction profile not predicted by the extended theory of X-ray diffraction was observed when the Bragg condition was at angles of incidence lower than 0.6 deg. Plane wave topographs revealed a contrast that could be explained by a slight residual crystal surface undulation of 0.3 deg due to etching to remove the cutting damage and the increasing effect of refraction at small glancing angles. |
Related projects: |