Molecular simulations of transport properties of polar hydrofluoroethers: Force field development, fractional Stokes-Einstein and free volume relations

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61388998%3A_____%2F23%3A00574386" target="_blank" >RIV/61388998:_____/23:00574386 - isvavai.cz</a>

Result on the web

<a href="https://www.sciencedirect.com/science/article/pii/S0167732223016525?via%3Dihub" target="_blank" >https://www.sciencedirect.com/science/article/pii/S0167732223016525?via%3Dihub</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.molliq.2023.122847" target="_blank" >10.1016/j.molliq.2023.122847</a>

Result language

angličtina

Original language name

Molecular simulations of transport properties of polar hydrofluoroethers: Force field development, fractional Stokes-Einstein and free volume relations

Original language description

Hydrofluoroethers (HFEs) having simultaneously hydrocarbon (HC) and fluorocarbon (FC) moieties connected through ether oxygen are polar chain molecules with dielectric properties, which makes them a good heat transfer medium, e.g., for cooling of electronics or magnetic devices. In this work, we report, validate, and test high level-ab initio derived force fields and we use partial charges fitted to the electrostatic potential surface (EPS) to reproduce the dipole moments. Computer simulations were performed over a wide range of temperatures and densities to calculate the transport coefficients in the condensed-phase and comparisons were made against available experimental data for five selected molecules, namely HFE-7000, HFE-7100, HFE −7200, HFE −7300, and HFE −7500. Furthermore, structural properties and enthalpy of vaporization were obtained from molecular simulations. Cohen and Turnbull formula for the translational self-diffusion coefficient was tested in the free-volume cast, which itself was correlated against the isothermal compressibility, which can explain the phenomenon of transport properties in liquids, D∝exp-γ/Vf/V∗. The fractional Stokes-Einstein relation was also tested to scale the self-diffusion coefficient vs viscosity in the form of (DT−1) ∝ (1/η)s, with s ranging between ≈ 0.89 and 0.92 for the five molecules in the reduced density range of ρσ3 = 0.56 to 0.75. Finally, the non-equilibrium molecular dynamics (NEMD) simulations of thermal conductivity was found to outperform the equilibrium Green-Kubo approach, but both with comparable accuracy.

Czech name

—

Czech description

—

Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

—

OECD FORD branch

20303 - Thermodynamics

Project

<a href="/en/project/GA22-03380S" target="_blank" >GA22-03380S: Aqueous mixtures with salts under extreme conditions – accurate experiments, molecular simulations and modeling</a><br>

Continuities

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year

2023

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Journal of Molecular Liquids

ISSN

0167-7322

e-ISSN

1873-3166

Volume of the periodical

389

Issue of the periodical within the volume

November

Country of publishing house

NL - THE KINGDOM OF THE NETHERLANDS

Number of pages

11

Pages from-to

122847

UT code for WoS article

001088428600001

EID of the result in the Scopus database

2-s2.0-85168408146