Certification of NIST Standard Reference Material 640d
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 silicon powder specially prepared to produce strain-free particles in a size range between 1 m and 10 m to eliminate size broadening effects. It is typically 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.
certification, lattice parameter, silicon, Standard Reference Material, x-ray diffraction