(580a) Integrated Kinetic Monte-Carlo Method to Find Face Specific Growth Rates

The morphology or shape of crystalline materials is a critical determinant of their physical properties such as bulk density, stability, wettability, flowability, and dissolution rates. For example, when plate- or needle-like morphologies appear in pharmaceutical crystals, granulation and compression are difficult when making tablets. The ability to use theoretical models to predict how the crystallization conditions will affect the crystal morphologies is imperative for developing control strategies to prevent the formation of undesired morphologies. Knowledge of face-specific growth rates of crystals is key for predicting dynamic and steady-state crystal morphologies. Current models rely on empiricism and calculation of interfacial free energies which are often difficult. In this talk, I will describe the multi-scale model for determining face specific growth rates using a Kinetic Monte-Carlo method. The kinetic, multi-scale model is used to capture the most fundamental mechanism that occur during crystallization – the association and dissociation of molecules – and determines the most probabilistic realization of the surface. Our method considers probabilities of events such as the nucleation of 2D islands, formation of screw dislocations, and the spreading of the layers. The velocity of the edges is based on the kinetic approach which calculates the energy barrier for integration of molecules into the crystal structure. The approach described in this talk will be exemplified on a glutamic acid crystal.