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Unit-cell refinement from powder diffraction scans

作者:G. S. Pawley · 发表于:Journal of Applied Crystallography · 年份:1981 · DOI:10.1107/s0021889881009618 · 被引用次数:1981 · 研究领域:X-ray Diffraction in Crystallography、Nuclear Physics and Applications、Crystallography and molecular interactions

A procedure for the refinement of the crystal unit cell from a powder diffraction scan is presented. In this procedure knowledge of the crystal structure is not required, and at the end of the refinement a list of indexed intensities is produced. This list may well be usable as the starting point for the application of direct methods. The problems of least-squares ill-conditioning due to overlapping reflections are overcome by constraints. An example, using decafluorocyclohexene, C 6 F 10 , shows the quality of fit obtained in a case which may even be a false minimum. The method should become more relevant as powder scans of improved resolution become available, through the use of pulsed neutron sources.