Prediction of crystal structure

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... 

Woodley SM (2004) Prediction of Crystal Structures Using Evolutionary Algorithms and... 

The prediction of crystal structures by ab initio quantum mechanical methods, and the identification of stable polymorphic forms and the conditions under which they will crystallize, is of great interest to the pharmaceutical industry. Some progress has been made towards this goal in recent years [17, 18] with a degree of success for small and conformationally simple pharmaceuticals. The methods are still a number of years away from routine use in the day to day research and development environment. 

Pannetier, J., Bassas-Alsina, J., Rodrigues-Carvajal, J., and Caignaert, V. (1990). Prediction of crystal structures from crystal chemistry rules by simulated annealing. Nature 346, 343-5. 

The exceptional large value of forbidden gap width seems to be any doubtful. Perhaps it means that not all of the calculations results obtained for small clusters can be used for prediction of crystal structures properties. Must be noted that calculated bonds lengths in squares and hexagons and period of crystal lattice (1.607 A, 1.452 A, 5.894 A) differ from the values (1.503 A, 1.380 A, 5.545 A), obtained in [8], However one can not expect the better accordance from the results of clusters calculations performed moreover in the frames of semi-empirical PM3-basis. 

This chapter is concerned with the assembly of supramolecular motifs based on H-bonding interactions between alcohols and amines. We shall name these supra-minols (see Section 1.3). Some useful insights about the effect of the structural and physical properties (as for example the chirality) of the component molecules on the structure and properties of the supramolecular product will be made whenever possible, even if it is widely accepted that predictions of crystal structures from knowledge of chemical composition of the components are far from being generalized [21]. 

In addition to structure determination from powder diffraction data as described earlier, another area of considerable current interest is the computational prediction of crystal structures based on energy simulation techniques. In such work, the potential energy, E(r), is computed as a function of the set of variables T that define the structure (the unit cell and space group are usually also included as variables in such calculations), and the E r) hypersurface is searched to find the structure of minimum energy. Representative examples of work in this field may be found in Refs. [74-79], and some work involving the use of evolutionary algorithms to carry out the search procedure has been reported [80-82]. 

Mooij, W. T. M. (2000). Ab initio prediction of crystal structures. Ph. D. Thesis, University of Utrecht, Utrecht, The Netherlands. [182]... 

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