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Institutsseminar

Title
Institutsseminar
Description

Studies of Crystallization in Supercooled Atomic Liquids

Dr. Robert Grisenti
Institut für Kernphysik, Goethe-Universität Frankfurt am Main

Abstract:

Freezing of a liquid is a ubiquitous change of state, but many aspects of this so familiar phase transition are still poorly understood. At the microscopic level, crystallization is classically viewed as a two-steps process. Thermal fluctuations in the supercooled liquid — that is, in the metastable state below its melting point — initially trigger the spontaneous formation of a critical nucleus of the new ordered phase, which subsequently grows to macroscopic dimensions. However, crystallization is by far more complex than represented by this classical description and many details of the process still lack an adequate microscopic understanding. Here, we combine x-ray scattering with microscopic liquid jets of the atomic elements argon and krypton as a powerful approach to the study of crystal nucleation and growth in supercooled liquids, ad- dressing the problems of very short time scale and the inherently stochastic nature of the crys- tallization process [1]. Our results highlight, for example, the importance of thermodynamic as- pects in describing the crystal growth kinetics in binary liquids [2] and provide stringent limits to the validity of classical nucleation theory in atomic liquids, while offering the long-sought per- spective of testing non-classical extensions of the theory [3]. Furthermore, in combination with computer simulations and state-of-the-art ML-based techniques for data analysis, we expect to be able to gain even deeper insights into many aspects of the crystallization process, providing new benchmarks for current theories of crystal nucleation and growth.

[1] Grisenti et al., Adv. Phys. X 3, 1418183 (2018)
[2] Schottelius et al., Nat. Mater. 19, 512 (2020)
[3] Möller et al., Phys. Rev. Lett., in review (2024)

Location
Seminarraum HI-Jena, Fröbelstieg 3
Date
08.02.2024