Particle Morphology and Surface Structure

Morphological simulations based on crystal lattice geometry were initially proposed [52-55]. Subsequent work focused on quantifying the crystal morphology in terms of the interaction energies between crystallising units [31,56]. Attachment and 

The external shape of crystals not only has a considerable influence on the properties of the solid but also has an impact on the handling of particulate materials and their interactions with the excipients used in product design. The shape of the growing crystals is influenced by a wide variety of factors as follows  

The crystallisation solvent is also an impurity and is present at very high concentrations around the crystal. Any of the mechanisms described for other impurities may also apply to the solvent and can produce similar changes in crystal habit. Finally, the interaction between solvent and crystal surface can change the surface energetics of the crystal faces due to the differential binding energies of solute and solvent on the different surfaces [58]. 

The modem process chemist has at their disposal tools that allow a link to be made between the bulk crystal chemistry, the surface chemistry of the crystal faces and their potential interactions with solvents and impurities. Examples of industrial application include aspirin [58], the agrochemical product paclobutrazol [59]. The subsequent sections in this chapter provide the details of how such an understanding of the intrinsic and extrinsic synthons can be used in the design of pharmaceutical products in particular addressing the challenges in form selection, particle fonnation and formulation design. 

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INVESTIGATION OF LATEX PARTICLE MORPHOLOGY AND SURFACE STRUCTURE OF CORRESPONDING COATINGS BY ATOMIC FORCE MICROSCOPY... 

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