| Abstract
| - The supramolecular synthon approach to crystal structure prediction (CSP) takes into accountthe complexities inherent in crystallization. The synthon is a kinetically favored unit, and through analysisof commonly occurring synthons in a group of related compounds, kinetic factors are implicitly invoked.The working assumption is that while the experimental structure need not be at the global minimum, it willappear somewhere in a list of computationally generated structures so that it can be suitably identified andranked upward using synthon information. These ideas are illustrated with a set of aminophenols, or aminols.In the first stage, a training database is created of the 10 isomeric methylaminophenols. The crystal structuresof these compounds were determined. The prototypes 2-, 3-, and 4-aminophenols were also included inthe training database. Small and large synthons in these 13 crystal structures were then identified. Smallsynthons are of high topological but low geometrical value and are used in negative screens to eliminatecomputationally derived structures that are chemically unreasonable. Large synthons are more restrictivegeometrically and are used in positive screens ranking upward predicted structures that contain thesemore well-defined patterns. In the second stage, these screens are applied to CSP of nine new aminolscarried out in 14 space groups. In each space group, up to 10 lowest energy structures were analyzedwith respect to their synthon content. The results are encouraging, and the predictions were classified asgood, unclear, or bad. Two predictions were verified with actual crystal structure determinations.
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