Understanding the role that solvent plays in crystal structure formation just got easier thanks to new software.

The Cambridge Structural Database (CSD) contains virtually all published small-molecule crystal structures. But extracting data from the CSD can be a time-consuming process. Software developed by Jacco van de Streek and Sam Motherwell at the Cambridge Crystallographic Data Centre, UK, could make this process much simpler. 

Motherwell and van de Streek developed a program that pairs up structures of solvated and unsolvated forms of the same molecule. The differences in the structures of these forms, which are influenced by the solvent used to grow them in, can then be analysed. 

Previously, extracting the relevant pairs would have required 35000 separate searches of the database and a total of over 11 billion comparisons of crystal structures. 'Clearly, these searches can no longer be done manually and specialised software therefore had to be developed,' said van de Streek. 

Susan Bourne, an expert in crystal engineering at the University of Cape Town, South Africa, welcomed the advance. 'Given the influence a solvent has on the structure obtained, this research is likely to have a strong impact on studies of polymorphs and potential co-crystal formers,' she said.

Sarah Dixon