Numerical modelling of complex interFACE shapes during crystal growth process: predicting the stability of faces with different surface energy and kinetic coefficients as a function of growth conditions – FACET
The aim of this project is to obtain a Phase-Field model and a simulation code that can simulate the shape of crystals for any anisotropic interface energy (?_(hkl)^SLl) and kinetics (Rhkl). So, the final objective of this project is improving the understanding of crystal growth process in order to decrease the large gap that exist between experiment and theory in this field. In a first step, the case study of the solution growth of KH2PO4 crystals, will be studied. To do so, one of the partners of this project (LPMC) will develop Phase-Field models with an arbitrary, nonlinear relationship between the driving force and interface velocity, while the other two (IN, CINaM) will determine the experimental values (?SLhkl, Rhkl, physicochemical parameters of the solutions) needed to “feed” this model. During the period development of Phase-Field models it will be a continuous feedback loop between simulation and experiments in order to validate and refine the choice of the mobility functions of the model. These models will then be tested and further extend to the simulation of other crystals: one organic ( paracetamol at the µ-droplet-based microfluidic platform at CINaM) and one inorganic (KTiOPO4 by high temperature solution growth method at IN). Each will allow addressing specific additions to the PF model. The organic compound, Paracetamol, presents growth shapes that are strongly influenced by the solvents. The inorganic compound, KTiOPO4, on the other hand presents a roughening transition at high temperature. From a fundamental point of view, and also for practical applications, it is of great importance to simulate the variation of growth shapes as a function of physicochemical parameters such as the viscosity as well as in determining the existence of roughening temperatures of given crystal faces. So, in summary, PF simulations will allow us to obtain a better understanding of the mechanisms involved in the development of thermodynamic facets, or of kinetic shapes as seen in the experiments. This project will then reinforce the collaboration between two teams with a long experience in crystal growth processes, IN and CINaM, and to begin a collaboration with LPMC, which means allowing to the growth community to have an interaction with the PF modelisation community. Having PF models able to simulate crystal growth processes is of utmost importance in order to being able to decrease the experimental time devoted to optimize these process. This time saving will lead to a strong economic impact which could attracts industry interest. An added value of this project is that, if successful, the simulation code will be made publicly available as an open source project, together with a user manual that will allow other to apply these methods to different systems. This will be highly beneficial for the improvement of the growth of many technologically important crystal (e.g. hybrid organic-inorganic perovskites, new piezoelectric materials, pharmaceutical).
Monsieur Bertrand Menaert (Institut Néel - CNRS)
The author of this summary is the project coordinator, who is responsible for the content of this summary. The ANR declines any responsibility as for its contents.
CINaM Centre National de la Recherche Scientifique Délégation Provence et Corse DR12
INEEL Institut Néel - CNRS
LPMC Laboratoire de physique de la matière condensée
Help of the ANR 471,770 euros
Beginning and duration of the scientific project: January 2020 - 48 Months