A proposal for the storage and dissemination of F (or F²) tables

The International Union of Crystallography (IUCr), through its Executive Committee, should take the initiative to organize the storage and availability of tables of Bragg intensities (F**2) or structure factors (F) from published and possibly also unpublished crystal structure analyses. Such tables constitute the primary experimental information on which these analyses are based and hence provide the only means of checking and extending their results. The earlier practice of printing F tables as integral parts of published papers has been abandoned for understandable reasons. A cursory check of major journals shows that only IUCr journals, the Chemical Society of Japan and the National Research Council of Canada still require deposition of F tables, and make them available on request. Such tables can now be stored as electronic files which can be made conveniently accessible to the crystallographic community and other scientists. The IUCr has the authority, experience and technical resources needed to mount such an initiative in cooperation with other publishers of papers containing crystallographic structural information.