Séminaire

Vendredi 11 Octobre 2019 à 11h00.

Molecular layer resolution of crystal growth in nanoconfinement

''L'équipe MMCI (Modélisation de la Matière Condensée et des Interfaces) invite le professeur Dag Kristian Dysthe de l'université d'Oslo. Abstract. Confined crystal growth is a common situation in Nature. Shells, coccoliths and human teeth and bones are minerals that are shaped partially by confinement. Crystallization in confinement can exert a pressure and cause rocks, concrete and bricks to break, destroying buildings and historical monuments all over the world. Almost all studies on crystal growth are, however performed in an environment where the effects of an additional interface can be neglected. In order to image the nanoconfined crystallization process in situ we developed an experiment based on reflection interference contrast microscopy. This allows in situ observations with spatial and temporal resolution that allows us to track the step flow of individual molecular layers of Ångstrøm thickness. Our experiments reveal details of different growth processes of our model system NaClO3, such as spiral growth from dislocations, 2D nucleation fluctuations, the birth of cavities, orientation dependent step flow in a concentration gradient and the appearance of a novel Mullins-Sekerka-like instability.''