Nucleation criteria detection as a mean to investigate metastable state

0544008 - ÚT 2022 RIV CZ eng C - Konferenční příspěvek (zahraniční konf.)
Celný, David - Span, R. - Vrabec, J.
Nucleation criteria detection as a mean to investigate metastable state.
Joint European Thermodynamics Conference. Praha: AMCA, spol. s r. o., 2021, s. 1-1.
[Joint European Thermodynamics Conference (JETC2021). Praha (CZ), 14.06.2021-18.06.2021]
Grant CEP: GA ČR(CZ) GA19-05696S
Institucionální podpora: RVO:61388998
Klíčová slova: metastable state * equation of state * molecular dynamics * cluster criterion
Obor OECD: Thermodynamics
https://www.jetc2021.eu/

Focus is given to the core problematic, reaching the nucleation region and sample the relevant data for selected pure substance. This termodynamic condition required for nucleation are found in so called metastable region. Metastable region is found between binodal and spinodal line separating it from the stable and unstable system condition respectively.
Obtaining the data in this area proves to be an experimental challenge, therefore the data has to be gathered using other means. Proposed setup relies two part approach combining equation of state (EoS) and molecular simulation. The computational core is done with molecular dynamics tool combined with on the fly performing decision cluster criterion utilized is already available in previously published work. These cluster criteria ensure that the system is only calculated within targeted conditions and the sampled micro-states remain valid observations. To capture whole metastable region two criteria are present for both cluster and void case as illustrated below. Remaining part utilize the equation of state for the initial system condition sampling of the metastable region by calculating the stability line and predicting the instability line for the LJ fluid as show in Linhart et.al. . These thermodynamic condition probes are evaluated afterwards with the established simulation method. Intermediate result from simulations are collected in form of both Helmholtz energy temperature and density derivatives descriptors as well as time averages of system properties for fluids like LJ, Oxygen and Nitrogen.
Trvalý link: http://hdl.handle.net/11104/0321152