W0172

PDF-4/Organics - New Content in a Relational Database Format with Integrated Search and Retrieval. C. R. Hubbard¹, J. Faber², S. Kabekkodu², and T. Fawcett², ¹Oak Ridge National Laboratory, Oak Ridge, TN, USA 37830-6064, ²International Centre for Diffraction Data.

The Powder Diffraction File (PDF), published by the International Centre for Diffraction Data (ICDD), is widely used for phase and polymorph identification by x-ray diffraction methods. In 1998 the ICDD reached and agreement with the Cambridge Crystallographic Data Center (CCDC) that allows for the calculation of x-ray powder patterns from the structural information in the Cambridge Structural Database (CSD). As a result of this agreement, the number of organic and pharmaceutical entries in the PDF has risen from ~25,000 to nearly 150,000 with the release of PDF-4/Organics. Another aspect of the agreement is insertion of cross pointers between the PDF and the CSD.

The PDF-4/Organics is distributed as a relational database (RDB) with integrated search and retrieval functions. Instrument and software companies that distribute the PDF are rapidly adopting this new file format and writing software to access the PDF-4/Organics. For stand-alone use, ICDD’s new viewing software has been integrated with the RDB. Search options include 31 searchable fields with ability to add more. Operators can be used to select a sub file of the PDF-4, which for the Organic 2003 file includes Drug Activity, Pharmaceuticals, Excipients, Forensics, Pigments, Polymers, and Explosives. Most entries for experimental patterns are characterized by organic functional group classifications. For nearly all entries a 2D structure can be exhibited as well as the powder pattern. The RDB format provides for exceptionally powerful data mining of this extensive database.