DISPLAY OF 3D CRYSTAL STRUCTURES OVER THE INTERNET USING VRML, FOR INORGANIC DATABASES. A.W. Hewat, ILL, BP 156X Grenoble Cedex 9, 38042 FRANCE

3D crystal structures can be displayed on all types of computer, even inexpensive home machines connected to the Internet, using the new Virtual Reality Modelling Language (VRML). Ball-and-stick, co-ordination polyhedrae, and space-filling models can be rotated in real time and zoomed to examine details of the structure.

Structural chemists might search the ICSD database, and display and compare the resulting inorganic structures on-line, just as structural biologists have already done with the Protein Data Bank and 'RasMol'. No special application like RasMol is needed with VRML, since the 3D viewer is a simple extension of Netscape and other WWW applications, and freely available.

The VRML file describing the 3D structure is simple ASCII, and as such can be saved, edited, forwarded by email, and transferred to any other computer for display. This file would be constructed on the remote server, following current ideas that WWW viewers need not even use complete computers.

Apart from the obvious interest to professional researchers, who will of course also continue to use commercial applications like BioSym/MSI's Cerius, this should help educate young people about chemistry and the importance of crystallography.

Anyone with a home computer and a telephone modem will be able to understand immediately the common structural elements of oxide superconductors, or the difference between alpha- and beta-quartz.

In this contribution, I will demonstrate how this might work in practice for the Inorganic Crystal Structure Database (ICSD). A demonstration database has already been set up for example, for superconductors, on the WWW at http://www.ill.fr/dif/3D_crystals.html.