Crystal structure prediction analysis

Progress in crystal structure prediction has been significant in recent years with parallel synthon-based and crystal structure calculation based approaches. Calculations are now sometimes able to correctly determine crystal structure in an ab initio fashion but analysis of synthons can give significant qualitative insight. 

However, crystal engineering did not become synonymous with supramolecular synthesis until die 1990s. As noted by J. S. Maddox in 19883 and more recendy by Gavezzotd17 and Ball,18 crystal structure prediction remains in its infancy. However, prediction is fundamentally very different from engineering and design. Predicting a crystal structure requires an analysis of the recognition features present in the molecular component in such... 

Cross WI, Blagden N, Davey ly, Pritchard RG, Neumann MA, Roberts ly, and Rowe RC. A Whole Output Strategy for Polymorph Screening Combining Crystal Structure Prediction, Graph Set Analysis, and Targeted Crystallization Experiments in the Case of Diflunisal. Cryst Growth Des 2003 3 151-158. 

Gavezzotti A (1994) Are crystal structures predictable Acc Chem Res 27 309-314 AUinger Nl, Miller MA, Van Catledge FA, Hirsh JA (1%7) Conformational analysis.LVIl. The calculation of the conformational structures of hydrocarbons by the Westheimer-Hendrickson-Wibetg method. 1 Am Chem Soc 89 4345 357... 

To assess the relative stabilities of the various stoichiometries, global minima were identified by crystal structure prediction and compared to the energy of 2 moles of crystalline caffeine and 2 moles of crystalline HBA. As before for caffeine, the lattice energy of the lowest energy crystal was used, ignoring the observed experimental disorder. 2-HBA has one known polymorph and 3-HBA and 4-HBA have two known polymorphs each. However, because of uncertainties in their structure determinations only one polymorph for each of 3-HBA and 4-HBA was considered in the analysis. 

Analysis of hterature on crystal structure prediction studies. 110... 

In 2000, Theresa Beyer completed her Ph.D. thesis on the computer prediction of organic crystal structures by performing a literature survey of all the published work on crystal structure prediction by lattice energy minimisation without knowledge of the unit cell parameters. The 64 papers covered 253 searches on 189 molecules, of which 29 were known to be polymorphic. The number of studies was too small for any meaningful statistical analysis [154] but highUghted the difference between the molecules... 

Chatfield C and A J CoHns 1980. Introduction to Multivariate Analysis. London, Chapman Hall. Desiraju G R 1997. Crystal Gazing Structure Prediction and Polymorphism. Sdence 278 404-405. Everitt B.S. 1993 Cluster Analysis. Chichester, John Wiley Sons. 

Crystallography is a very broad science, stretching from crystal-structure determination to crystal physics (especially the systematic study and mathematical analysis of anisotropy), crystal chemistry and the geometrical study of phase transitions in the solid state, and stretching to the prediction of crystal structures from first principles this last is very active nowadays and is entirely dependent on recent advances in the electron theory of solids. There is also a flourishing field of applied crystallography, encompassing such skills as the determination of preferred orientations, alias textures, in polycrystalline assemblies. It would be fair to say that... 

The pattern of hydrogen bonding between a pair of acylurea derivatives revealed by X-ray analysis was consistent with that predicted by spectroscopic studies. Typical examples are illustrated in Figs. 11 and 12 35-37) two NH — O intermolecular hydrogen bonds connect the two molecules. This holds true for the other acylurea derivative 20 (R8 = CH2Ph)38) and 1 1 complexes whose crystal structures were so far determined. 

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