ISSN:
1600-5724
Source:
Crystallography Journals Online : IUCR Backfile Archive 1948-2001
Topics:
Chemistry and Pharmacology
,
Geosciences
,
Physics
Notes:
The instrumental window of a double crystal spectrometer in the dispersive (1, +1) position has been determined experimentally with a Mössbauer source and compared with theoretical predictions. The experiment was done at a wavelength of 0.86 Å* with the 14.4 keV γ ray that follows the 57Co→57Fe decay. The crystals employed were quartz (10{\bar 1}1), silicon (111), germanium (111), and calcite (211) (10{\bar 1}4), where the indices refer to the structural cells. The theoretical expression for the double-crystal window was calculated as the convolution of the appropriate single-crystal monochromatic profiles predicted by the Darwin–Prins dynamical theory of X-ray diffraction. The agreement between theory and experiment was good and clearly shows the necessity for crystal asymmetry corrections to precision wavelength determinations in certain cases.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1107/S0567739468000495
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