skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Diffusion at the liquid-vapor interface of an aqueous ionic solution utilizing a dual simulation technique

Journal Article · · Journal of Physical Chemistry B
DOI:https://doi.org/10.1021/jp051226x· OSTI ID:15017416

The recently proposed dual simulation technique [J. Phys. Chem. B 2004, 108, 6595.] is used to determine the diffusion coefficients for a variety of regions of a 2.2 sodium chloride aqueous solution with a vapor-liquid interface. For the calculation of the diffusion coefficient perpendicular to the interface, a modest modification to the dual simulation method was applied, while values parallel to the interface were determined without any modification to the method. Tests were performed, verifying the quality of modified method, showing it to be a well-defined self-consistent technique for the determination of the diffusion coefficient perpendicular to the interface. The diffusion of all species was shown to be isotropic far away from the interface, as expected, but at different regions in the interface, the diffusion coefficients parallel and perpendicular to the interface were not the same. Specifically, for water the diffusion coefficient perpendicular to the interface was higher in the liquid edge of the interface, but at the low density region, an opposite trend could be observed. For sodium and chloride ions, the diffusion parallel to the interface was higher than the values perpendicular to the interface near their concentration peaks. The diffusion of all species was generally higher at the vapor-liquid interface than in the middle of the liquid.

Research Organization:
Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
Sponsoring Organization:
USDOE
DOE Contract Number:
AC05-76RL01830
OSTI ID:
15017416
Report Number(s):
PNNL-SA-44441; KC0301020; TRN: US200517%%403
Journal Information:
Journal of Physical Chemistry B, Vol. 109, Issue 32
Country of Publication:
United States
Language:
English