ISSN:
1600-5724
Source:
Crystallography Journals Online : IUCR Backfile Archive 1948-2001
Topics:
Chemistry and Pharmacology
,
Geosciences
,
Physics
Notes:
The neutron diffraction powder pattern of UO2 has been recorded at five temperatures between 293 and 1733 K, and the data have been analysed by two methods: the Rietveld profile-refinement procedure and the more conventional approach based on independent integrated intensities. The structural parameters (i.e. the thermal amplitudes of the U and O atoms) derived by the two methods do not differ significantly, but the e.s.d.'s of the parameters given by the Rietveld treatment differ at some temperatures from those obtained by the conventional analysis. These results are discussed in the light of the statistical analysis of the Rietveld procedure published by Sakata & Cooper [J. Appl. Cryst. (1979), 12, 554-563]. At the higher temperatures, the observed mean-square displacements of the U atoms are larger than those calculated by Dolling, Cowley & Woods [Can. J. Phys. (1965), 43, 1397-1413 ] from the analysis of room-temperature phonon dispersion curves.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1107/S0567739480000526
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