2017/05/31 by Barbora Planková, Václav Vinš, Jan Hrubý +1 · 5 citations
Chemistry · Earth and Planetary Sciences · Engineering · Physics and Astronomy · #Advanced Thermodynamics and Statistical Mechanics #Capillary action #Capillary wave #Chemistry #Classical nucleation theory #Condensed matter physics #Equation of state #Homogeneous #Nucleation #Optics #Phase Equilibria and Thermodynamics #Physics #Statistical physics #Surface tension #Thermodynamics #Wavelength #Work (physics) #nanoparticles nucleation surface interactions #physics.class-ph #physics.comp-ph
paper · pdf · doi:10.1063/1.5008612
published in The Journal of Chemical Physics 147(16), 164702 (American Institute of Physics) · 16 pages, 16 figures
openalex created_date 2017/06/05 · openalex publication_date 2017/10/23 · arxiv created 2018/12/06 · arxiv updated 2018/12/07 · openalex updated_date 2026/08/05
Homogeneous droplet nucleation has been studied for almost a century but has not yet been fully understood. In this work, we used the density gradient theory (DGT) and considered the influence of capillary waves (CWs) on the predicted size-dependent surface tensions and nucleation rates for selected n-alkanes. The DGT model was completed by an equation of state (EoS) based on the perturbed-chain statistical associating fluid theory and compared to the classical nucleation theory and the Peng-Robinson EoS. It was found that the critical clusters are practically free of CWs because they are so small that even the smallest wavelengths of CWs do not fit into their finite dimensions. The CWs contribute to the entropy of the system and thus decrease the surface tension. A correction for the effect of CWs on the surface tension is presented. The effect of the different EoSs is relatively small because by a fortuitous coincidence their predictions are similar in the relevant range of critical cluster sizes. The difference of the DGT predictions to the classical nucleation theory computations is important but not decisive. Of the effects investigated, the most pronounced is the suppression of CWs which causes a sizable decrease of the predicted nucleation rates. The major difference between experimental nucleation rate data and theoretical predictions remains in the temperature dependence. For normal alkanes, this discrepancy is much stronger than observed, e.g., for water. Theoretical corrections developed here have a minor influence on the temperature dependency. We provide empirical equations correcting the predicted nucleation rates to values comparable with experiments.