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Standard Reference Material 640d for X-ray Metrology



David R. Black, Donald A. Windover, Albert Henins, David L. Gil, James J. Filliben, James P. Cline


The National Institute of Standards and Technology (NIST) certify a variety of standard reference materials (SRM) to address specific aspects of instrument performance for divergent beam diffractometers. This report describes SRM 640d, the fifth generation of this powder diffraction SRM which is certified with respect to lattice parameter. It consists of approximately 7.5 g of silicon powder specifically prepared to produce strain-free particles in the size range between 1 m and 10 m to eliminate size broadening effects. It is commonly used for calibrating powder diffractometers for line position and line shape. A NIST built diffractometer, incorporating many advanced design features, was used to certify the lattice parameter of the silicon powder. Both Type A, statistical, and Type B, systematic, errors have been assigned to yield a certified value for the lattice parameter of a = 0.543159 nm  0.000020 nm.
Proceedings Title
Advances in x-ray analysis, proceedings of 58th DXC
Conference Dates
July 27-31, 2009
Conference Location
Colorado Springs, CO
Conference Title
58th Denver X-ray Conference


calibration, powder diffraction, SRM


Black, D. , Windover, D. , Henins, A. , Gil, D. , Filliben, J. and Cline, J. (2010), Standard Reference Material 640d for X-ray Metrology, Advances in x-ray analysis, proceedings of 58th DXC, Colorado Springs, CO (Accessed June 13, 2024)


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Created June 1, 2010, Updated February 2, 2018