How Is the Surface Tension of Various Liquids Distributed along the Interface Normal?

Author(s)
Marcello Sega, Balazs Fabian, George Horvai, Pal Jedlovszky
Abstract

The tangential pressure profile has been calculated across the liquid-vapor interface of five molecular liquids, i.e., CCl

4, acetone, acetonitrile, methanol, and water, in molecular dynamics simulations using a recently developed method. Because the value of the surface tension is directly related to the integral of this profile, the obtained results can be interpreted in terms of the distribution of the surface tension along the interface normal, both as a function of distance, either from the Gibbs dividing surface or from the capillary wave corrugated real, intrinsic liquid surface, and also in a layerwise manner. The obtained results show that the surface tension is distributed in a 1-2 nm wide range along the interface normal, and at least 85% of its value comes from the first molecular layer of the liquid in every case. The remaining, roughly 10% contribution comes from the second layer, with the exception of methanol, in which the entire surface tension can be accounted for by the first molecular layer. Contributions of the third and subsequent molecular layers are found to be already negligible in every case. (Graph Presented).

Organisation(s)
Computational and Soft Matter Physics
External organisation(s)
Budapest University of Technology and Economics, Université de Franche-Comté, Eszterházy Károly University of Applied Sciences
Journal
The Journal of Physical Chemistry Part C (Nanomaterials and Interfaces)
Volume
120
Pages
27468-27477
No. of pages
10
ISSN
1932-7447
DOI
https://doi.org/10.1021/acs.jpcc.6b09880
Publication date
12-2016
Peer reviewed
Yes
Austrian Fields of Science 2012
103006 Chemical physics, 103018 Materials physics
Keywords
ASJC Scopus subject areas
Electronic, Optical and Magnetic Materials, Energy(all), Surfaces, Coatings and Films, Physical and Theoretical Chemistry
Portal url
https://ucris.univie.ac.at/portal/en/publications/how-is-the-surface-tension-of-various-liquids-distributed-along-the-interface-normal(9d50b542-ce40-4c4a-b434-fc74cc58f643).html