
Research Project: Modelling of Crystal Polymorphism and Crystal
Morphology
Crystallisation is a subtle interplay of intermolecular and
supramolecular interactions, kinetics and thermodynamics. Polymorphism occurs when
molecules can find more than one way of interacting favourably to form
different crystal structures.
Polymorphism is important for for instance the pharmaceutical industry.
The crystal structure determines the way in which an active compound is
taken up in the body. As over 90% of all drugs is administered in
powder crystalline form, this is an important aspect of drug
formulation.
Crystal morphology,
i.e. the crystal shape, is an important parameter in the design of
crystallisation processes. The morphology determines the crystals'
drying, filtering and flow properties.
This project is a collaboration between Synthon B.V. and the IMM Department of
Solid State Chemistry of the Radboud University Nijmegen. In this
project polymorphism is modelled by the polymorph prediction scheme
implemented in Cerius2 . Crystal morphology is modelled
with the attachment energy model and with kinetic Monte Carlo simulations. We are also
interested in step energies in crystal graphs and I am developing a
program called STEPLIFT for
this purpose.