Crystal clear

UK scientists are using computational and NMR methods to predict three-dimensional crystalline structures.

The way a compound crystallises depends on a number of factors: temperature, dilution, solvent and pressure, to name a few. It is difficult to make predictions about crystallisation when there are so many variables. By looking at specially selected systems at different concentrations, Christopher Hunter from the University of Sheffield and his colleagues from AstraZeneca were able to see how molecules aggregated in solution and what relationship that had with the final crystal structure. Their techniques involved NMR studies and computer modelling, using genetic algorithms to find a match between experimental and calculated values for the molecule’s conformational properties as they crystallised.

The team is confident that now, using its models and methodology, it will be possible to say in advance how a solution is likely to behave as it crystallises.

Katharine Sanderson