Attachment energy model, growth form

Fig. 4. A Unit cell of stearic acid (E form) while, hydrogen atoms gray, carbon atoms and black, oxygen atoms. Theoretical habit of stearic acid B growth form according to the BFDH law C growth form according to the attachment energy model.

The processes of crystallization and crystal growth, like many other processes in chemistry, are controlled by thermodynamic and kinetic factors. Thermodynamics will dictate the preferred, lowest energy form, but the rate at which this is achieved will depend on the processes involved in the molecular attachment kinetic factors. In the simplest model, the molecules are placed at the points of lowest energy on the ideal lattice structure. It is usually assumed that the entity that is being attached is a single molecule however, it could also be a dimer or a cluster of molecules. In certain situations, for instance growth of benzoic acid from a non-polar solvent, the entity which may be involved is a dimer or higher order cluster ... 

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