CONCORD AND CAMBRIDGE - COMPARISON OF COMPUTER-GENERATED CHEMICAL STRUCTURES WITH X-RAY CRYSTALLOGRAPHIC DATA

The structures of a number of molecules as determined by X-ray crystallography have been compared with the structures for the same molecules as calculated by the 3D structure generation program, CONCORD. In 41% of the cases, the calculated structures were essentially identical to those measured by X-ray diffraction. In most of the remainder, there were significant differences arising primarily from the inability of the structure generation program to predict the correct torsion angle at one or more rotatable bonds. The implications of these findings on the process of 3D database generation are discussed.