The WPCI first convened at the 1988 ECM11 conference in Vienna. In the discussions leading up to this meeting, it was widely appreciated that electronic submissions to journals and databases involved data types (e.g. manuscript texts, graphical diagrams, the full suite of crystallographic data) that were beyond those accommodated within the SCFS format promoted by the IUCr Data and Computing Commissions. Consequently, it was suggested at the Vienna meeting that a general and extensible universal file approach, similar to the recently developed Self-defining Text Archive and Retrieval (STAR) File format (Hall, 1991; Hall & Spadaccini, 1994), might also be suitable for crystallographic data applications.

At this meeting, it was decided that a WPCI working group, led by Syd Hall, should investigate the development of a universal file protocol that would be suitable for crystallographic data needs. Other universal formats existed, such as ASN.1 (ISO, 2002), which was used for data communications, JCAMP-DX (McDonald & Wilks, 1988), which was used for archiving infrared spectra, and the Standard Molecular Data (SMD) format (Barnard, 1990), which was used for the global exchange of chemical structure data. These were considered relatively inefficient for expressing the repetitive data lists commonly used in crystallography. The working group eventually proposed a Crystallographic Information File (CIF) format which had a syntax similar to, but simpler than, the STAR File. Of particular importance because of the rapid changes taking place with data types, the CIF approach provided a very flexible and extensible file structure in which any type of text or numerical data could be arranged in any order. The typical data structure of a CIF is illustrated in Fig. 1.1.6.1, using the same data as presented in the PDB file of Fig. 1.1.3.1. Similarly, Fig. 1.1.6.2 shows the data in the BCCAB file of Fig. 1.1.3.2 in CIF format.

Figure 1.1.6.1 | top | pdf | Example 1 of a CIF (using the same data as shown in Fig. 1.1.3.1).

Figure 1.1.6.2 | top | pdf | Example 2 of a CIF (using the same data as shown in Fig.1.1.3.2).