Joint Committee for Powder Diffraction Studies

The Joint Committee for Powder Diffraction Studies (JCPDS) maintains a database of diffraction patterns, the Powder Diffraction File (PDF), including the d-spacings (related to angle of diffraction) and relative intensities of observable diffraction peaks. Patterns may be experimentally determined, or (preferably) computed based on crystal structure and Bragg's law. It is most often used to identify substances based on x-ray diffraction data, and is designed for use with a diffractometer. The database is exhaustive, with 163,835 entries as of 2004; computer algorithms allow rapid peak matching.

External Links

• History, contents & use of the PDF