No CrossRef data available.
Article contents
Accurate Determination of Unit-Cell Parameters using Conventional X-Ray Powder Diffractometry
Published online by Cambridge University Press: 06 March 2019
Abstract
A procedure for the accurate determination of unit-cell parameters using conventional Xray powder diffractometry is described. Two important factors in the procedure are: 1) the use of high-resolution-type diffractometer, which can suppress the axial beam divergence and thus gives nearly symmetric diffraction profiles in the low 2θ region and 2) the use of a new algorithm for systematic peak shift correction during the least-squares determination of unit-cell parameters of a sample with an internal standard [Toraya & Kitamura (1990). J. Appl. Cryst. 23 , 282-285]. The procedure has been tested by measuring successively the unit-cell parameter of W, CeO2, and Si in three mixtures, Si+W, W+CeO2, and CeO2+Si: the unit-cell parameter of W, which was first determined by using NIST SRM 640b Si powder as an internal standard reference material, was used as a standard reference value to determine the unit-cell parameter of CeO; in the next W+CeO2 mixture, and so on. The difference between the end value of observed Si unit-cell parameters and the starting value of 5.430940(35) Å were just 1 to 5 p.p.m. High accuracy is attainable in measuring the uni-cell parameters even with the conventional powder diffractometry provided with the nearly symmetric diffraction profile and the algorithm for peak shift correction used in the present study.
- Type
- VI. XRD Instrumentation, Techniques and Reference Materials
- Information
- Copyright
- Copyright © International Centre for Diffraction Data 1991