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Updated: Nov 27, 2025
On-Chip Crystallization and Large-Scale Serial Diffraction at Room Temperature
Published on: March 11, 2022
Capturing Crystal Shape Evolution from Molecular Simulations
Ekaterina Elts1, Heiko Briesen1
1Chair for Process Systems Engineering, TUM School of Life Sciences, Technical University of Munich, Freising, Germany.
Abstract:
A simple and efficient algorithm for tracking shape evolution of small-molecule organic crystals during molecular simulations is described. It is based on the reconstruction of a crystal surface from molecular coordinates using an alpha-shape triangulation algorithm followed by the DBSCAN clustering of neighboring triangles with similar normal vectors to crystal faces. No information except the unit cell parameters is needed beforehand, enabling the user to automatically detect not only existing but also new forming crystal faces and edges, which is valuable for prediction of growth and dissolution kinetics. The results are demonstrated for aspirin and paracetamol crystals.
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