Prequest: 2.13 Paste 2D
PreQuest automatically assigns chemical bond types according to CSD standard practices (e.g. all nitro groups will be coded the same way). Each chemically discrete bonded molecule is taken separately and a search for the minimum overlap view is performed. The molecules are then arranged in a vertical stacked manner. The diagrams may be simplified by use of the CSD standard group symbols e.g. Ph for phenyl (see Vol III. Appendix 8 and Section 2.16).
The process is highly successful for organic compounds and will even work in the complete or partial absence of hydrogen atoms. There may be occasional ambiguities, and some metal complexes and delocalised-charge systems are known to give problems, so these should always be visually checked in the 2D window.
If the diagram is not acceptable it can be edited using 2D Edit.