title: Effects of the surroundings and conformerisation of n-dodecane molecules on evaporation/condensation processes.
abstract: 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/Tc < 0.8) or slightly larger (at T/Tc > 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 the critical temperature.
authors.affiliation: Chuiko Institute of Surface Chemistry, 17 General Naumov Street, Kiev 03164 Ukraine.
authors.forename: Vladimir M
authors.initials: VM
authors.lastname: Gun'ko
authors.affiliation: Sir Harry Ricardo Laboratories, School of Computing, Engineering and Mathematics, University of Brighton, Cockcroft Building, Lewes Road, Brighton BN2 4GJ, United Kingdom.
authors.forename: Rasoul
authors.initials: R
authors.lastname: Nasiri
authors.affiliation: Sir Harry Ricardo Laboratories, School of Computing, Engineering and Mathematics, University of Brighton, Cockcroft Building, Lewes Road, Brighton BN2 4GJ, United Kingdom.
authors.forename: Sergei S
authors.initials: SS
authors.lastname: Sazhin
mesh_terms: D000473:Alkanes / Q000737:chemistry*; D005740:Gases / Q000737:chemistry; D056004:Molecular Dynamics Simulation; D044367:Phase Transition; D011312:Pressure; D011789:Quantum Theory; D012997:Solvents / Q000737:chemistry; D013696:Temperature
chemical_list: D000473:Alkanes; D005740:Gases; D012997:Solvents; C007548:n-dodecane