Abstract:
The kinetics of a spontaneous formation of liquid phase in a stretched (superheated) Lennard-Jones fcc crystal is studied. Molecular dynamics experiments are used to determine the main parameters of the nucleation process: nucleation frequency JJ, diffusion coefficient of nuclei
D∗D∗, nonequilibrium Zel'dovich factor ZZ, and critical nucleus size R∗R∗. The calculations are performed at negative pressures from the endpoint of the melting line and at positive pressures that are higher by a factor of eight than the critical pressure. The simulation results are compared to the classical homogeneous nucleation theory. It is found that the theory qualitatively correctly reproduces the dynamics of developing the process. The theory and the simulation demonstrate good quantitative agreement for the transition rate of the liquid phase nucleus through the critical size, but there is large difference in the numbers of critical nuclei in the unit volume of the metastable phase. In the case of significant superheatings and negative pressures, the contribution of the energy of elastic stresses to the moving force of the phase transformation is small and it can be neglected in a first approximation. The mismatch between the theory and the simulation results can be eliminated taking that the surface free energy of a curved “crystal–liquid droplet” interface is smaller than that of a plane interface by 30–35%.
Citation:
V. G. Baidakov, A. O. Tipeev, “The kinetics of the liquid phase nucleation in a stretched FCC crystal: a molecular dynamics simulation”, Fizika Tverdogo Tela, 60:9 (2018), 1803–1810; Phys. Solid State, 60:9 (2018), 1853–1860
\Bibitem{BaiTip18}
\by V.~G.~Baidakov, A.~O.~Tipeev
\paper The kinetics of the liquid phase nucleation in a stretched FCC crystal: a molecular dynamics simulation
\jour Fizika Tverdogo Tela
\yr 2018
\vol 60
\issue 9
\pages 1803--1810
\mathnet{http://mi.mathnet.ru/ftt9088}
\crossref{https://doi.org/10.21883/FTT.2018.09.46402.034}
\elib{https://elibrary.ru/item.asp?id=36903702}
\transl
\jour Phys. Solid State
\yr 2018
\vol 60
\issue 9
\pages 1853--1860
\crossref{https://doi.org/10.1134/S1063783418090032}
Linking options:
https://www.mathnet.ru/eng/ftt9088
https://www.mathnet.ru/eng/ftt/v60/i9/p1803
This publication is cited in the following 2 articles:
Willem Gispen, Marjolein Dijkstra, “Finding the differences: Classical nucleation perspective on homogeneous melting and freezing of hard spheres”, The Journal of Chemical Physics, 160:14 (2024)
Joachim Deubener, Jürn W. P. Schmelzer, “Statistical Approach to Crystal Nucleation in Glass-Forming Liquids”, Entropy, 23:2 (2021), 246