Homogeneous nucleation kinetics of polymorphic phases in solution

0483457 - FZÚ 2018 RIV ES eng A - Abstract
Kožíšek, Zdeněk - Tahri, Y. - Gagniere, E. - Bounahmidi, T. - Mangin, D.
Homogeneous nucleation kinetics of polymorphic phases in solution.
Book of abstracts of the 3rd World Congress on Materials Science, Engineering, Oil, Gas and Petrochemistry. Barcelona: Scientific Future Group, 2017. s. 59-59.
[3rd World Congress on Materials Science, Engineering, Oil, Gas and Petrochemistry. 24.08.2017-26.08.2017, Barcelona]
R&D Projects: GA MŠMT LD15004
Institutional support: RVO:68378271
Keywords : nucleation kinetics * polymorphic phases
OECD category: Condensed matter physics (including formerly solid state physics, supercond.)

In our model, which includes nucleation, growth, and Ostwald ripening, the number density of nuclei of polymorphic phases is determined by numerical solution of kinetic equations. As a model system the L-glutamic acid (LGlu), which exhibits two monotropic polymorphs: a LGlu and b LGlu, was considered. Decrease of supersaturation during phase transition, due to formation of polymorphic phases, was taken into account. The critical sizes of nuclei of both phases increase with time as supersaturation decreases. Consequently, supercritical nuclei become undercritical and have tendency to diminish. The number of subcrictical clusters decreases, i.e. nucleation rate reaches negative values.
Such a behavior is in coincidence with Ostwald rule of stages, when large particles growt at the expense of small particles. Numerical results reflects well known experimental data at temperatures T=5, 20 and 40 oC.
Permanent Link: http://hdl.handle.net/11104/0278759