Notices

Update from the CCDC

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Currently, the Cambridge Structural Database (CSD) contains over 290,000 structures, including the February and April data updates, available to subscribers via the Web, and a target of 300,000 structures will be close by the time of next full CSD System release in November 2003. As the number of CIFs deposited with the CCDC continues to rise exponentially, it is appropriate that April saw the release of the long-awaited CIF editor: enCIFer (version 1.0) from the CCDC. enCIFer is available for free download for bona fide research purposes from: www.ccdc.cam.ac.uk/prods/encifer/index.html.

The CIF (Crystallographic Information File) is now the standard means of information exchange in crystallography. An increasing number of journals require CIF depositions to be associated with new papers, and some generate papers for publication directly from CIFs. It is also the (much) preferred way of submitting data to the CSD. Being text files, CIFs can be manually edited or amended, and if this is not done correctly, programs designed to read and interpret CIF data will encounter problems. It is for this reason that enCIFer has been written.

enCIFer provides an intuitive interface which, having finished a crystal structure refinement, allows you to add information, e.g. bibliographic data, crystal properties, etc., safely to the resultant CIF without corrupting the strict syntax, giving rise to a format compliant file. Additionally, enCIFer has been designed to suit expert and novice CIF editors alike. Feedback from beta-testers has been encouraging, so please try it in your laboratory and let us know what you think (support@ccdc.cam.ac.uk).

Single and multi-block CIFs can be edited using enCIFer permitting:

  • Location and reporting of syntax/format violations using the current CIF dictionary
  • Correction of these syntax/format violations
  • Editing of existing individual data items or looped data items
  • Addition of new individual data items or looped data items
  • Addition of certain standard additional information via two data entry wizards: Publication wizard – basic bibliographic information required by most journals and databases that acceptCIF deposition files; Data wizard – chemical, physical and crystallographic property information that enhances a CIF for journal or database deposition
  • 3D visualisation of structure(s) in a CIF

Many journals have arrangements whereby the CIF is deposited with the CCDC before the paper is submitted for publication. The CCDC also accepts Private Communications for structures for which formal journal publication is not envisaged. Full details about both data deposition schemes can be found on the CCDC website: www.ccdc.cam.ac.uk/conts/depositing.h

Karen Lipscomb and Susan Robertson from ACA Newsletter, Summer 2003