(279d) A Mathematical Model to Describe the Oriented Attachment of Molecules in Crystal Growth.

In the classical view, the attachment of a single molecule/atom to the nucleus leads to crystal growth. However, non-classical mechanisms are also common in crystallization literature for the past two to three decades. Irrespective of the nucleation mechanism, solute molecules
first diffuse from bulk to the nucleus surface and orient themselves to be part of the growing crystal. The orientational ordering of molecules is crucial for crystal growth, for example, maintaining a hydrogen-bonded network and crystal polymorphism. Oriented attachment of molecules plays a vital role in deciding the outcome of the crystallization process. Overall, we see this process as diffusion-limited. Hence, we present a mathematical model to study the oriented attachment of disc-shaped molecules near the absorbing surface. The proposed model is rigorous and simple to describe the oriented attachment of molecules to crystal growth. This model will also help study of biomolecules' interaction with the target surfaces, which requires many direction-specific interactions.