Author:

Keywords:

microgravity, crystallisation, General Physics

Abstract:

Aggregation and crystal nucleation phenomena are among the subjects in condensed matter physics that still deserve a strong experimental effort to be fully grasped, in particular when they refer to macromolecular solutions or to dispersions of particles in the colloidal size range. Self-assembly, spontaneous ordering, structural organization on mesoscopic scales, are moreover key concepts for the design of nanostructured materials with specific functional properties. Although ground-based experiments performed on model systems have already shed light on many aspects of the latter phenomena, the presence of gravity often plays a noxious role. Density gradients induced by fast settling of large aggregates, or convective effects associated to the depletion zone around growing crystallites are just two well-known examples, but gravity often yields additional and rather unexpected effects.