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Title: Effects of the surroundings and conformerisation of n-dodecane molecules on evaporation/condensation processes

The evaporation/condensation coefficient (β) and the evaporation rate (γ) for n-dodecane vs. temperature, gas pressure, gas and liquid density, and solvation effects at a droplet surface are analysed using quantum chemical density functional theory calculations of several ensembles of conformers of n-dodecane molecules in the gas phase (hybrid functional ωB97X-D with the cc-pVTZ and cc-pVDZ basis sets) and in liquid phase (solvation method: SMD/ωB97X-D). It is shown that β depends more strongly on a number of neighbouring molecules interacting with an evaporating molecule at a droplet surface (this number is estimated through changes in the surface Gibbs free energy of solvation) than on pressure in the gas phase or conformerisation and cross-conformerisation of molecules in both phases. Thus, temperature and the surrounding effects at droplet surfaces are the dominant factors affecting the values of β for n-dodecane molecules. These values are shown to be similar (at reduced temperatures T/T{sub c} < 0.8) or slightly larger (at T/T{sub c} > 0.8) than the values of β calculated by the molecular dynamics force fields (MD FF) methods. This endorses the reliability of the previously developed classical approach to estimation of β by the MD FF methods, except at temperatures close to themore » critical temperature.« less
Authors:
 [1] ;  [2] ; ;  [3]
  1. Chuiko Institute of Surface Chemistry, 17 General Naumov Street, Kiev 03164 Ukraine (Ukraine)
  2. (United Kingdom)
  3. Sir Harry Ricardo Laboratories, School of Computing, Engineering and Mathematics, University of Brighton, Cockcroft Building, Lewes Road, Brighton BN2 4GJ (United Kingdom)
Publication Date:
OSTI Identifier:
22416019
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Chemical Physics; Journal Volume: 142; Journal Issue: 3; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; CRITICAL TEMPERATURE; DENSITY; DENSITY FUNCTIONAL METHOD; DODECANE; DROPLETS; EVAPORATION; FREE ENTHALPY; HYBRIDIZATION; LIQUIDS; MOLECULAR DYNAMICS METHOD; MOLECULES; RELIABILITY; SOLVATION; SURFACES