In-situ study of the crystallization dynamics of organic materials with harmonic light scattering

Promovendus/a: Karen Aerts

Promotor(en): Prof. dr. Thierry Verbiest, De heer Yovan de Coene

Crystals play a crucial role in fields from medicine to materials science, with researchers hoping to design crystals with specific, useful properties. But to do so, we first need to understand how crystals start forming at the tiniest molecular scale. My research takes on this challenge by developing a custom optical setup that allows us to observe the earliest moments of crystallization in real time, across various types of molecules.

Our setup combines advanced optical techniques to capture highly detailed snapshots of molecules as they move toward crystallizing. Using this tool, I discovered that tiny clusters often form before the crystals themselves—an unexpected finding that goes against traditional theories. This discovery could lead to new ways of controlling crystal properties by fine-tuning these early clusters.

For example, I found that certain polymer molecules take a similar pre-aggregation path before crystallizing, no matter their size. And in the case of chiral polymers (which have unique shapes, like left- or right-handedness), we uncovered the different mechanisms that lead to distinct types of crystal structures. This insight could be valuable in tailoring crystals for specific purposes.

We even applied this setup to study chlorophyll b, the molecule plants use to absorb sunlight. By observing its early aggregation stages, we hope to pave the way for more efficient synthetic light-harvesting materials, inspired by nature’s design.