Revolutionary images of the birth of crystals

The scientists used lasers to reveal the molecular structure at work during nucleation, but also to induce nucleation and observe its spectral fingerprint. Oscar Urquidi - A team from the UNIGE has succeeded in visualizing crystal nucleation - the stage that precedes crystallization - that was invisible until now. At the interface between chemistry and physics, the process of crystallization is omnipresent in nature and industry. It is the basis for the formation of snowflakes but also of certain active ingredients used in pharmacology. For the phenomenon to occur for a given substance, it must first go through a stage so-called nucleation, during which the molecules organize themselves and create the optimal conditions for the formation of crystals. While it has been difficult to observe this pre-nucleation dynamics, this key process has now been revealed by the work of a research team from the University of Geneva. The scientists have succeeded in visualizing this process spectroscopically in real time and on a micrometric scale, paving the way to the design of safer and more stable active substances.