Surface tension and viscosity of carbon dioxide near the critical point using molecular dynamics simulations and surface light scattering

Sanchouli N, Kankanamge CJ, Fröba AP, Koller TM (2026)

Publication Language: English

Publication Type: Journal article, Original article

Publication year: 2026

Journal

Fluid Phase Equilibria Elsevier

Book Volume: 605

Article Number: 114660

DOI: 10.1016/j.fluid.2026.114660

Abstract

The present study investigates the surface tension and viscosity of carbon dioxide (CO2) in the vicinity of the critical point using molecular dynamics (MD) simulations and surface light scattering (SLS). The latter technique was applied to simultaneously obtain the sum of the dynamic shear viscosities of the liquid phase, ηL, and vapor phase, ηV, as well as the surface tension σ at macroscopic thermodynamic equilibrium at temperatures T from (283.15 to 303.65) K, corresponding to reduced temperatures TR from 0.931 to 0.998. The measurement results for (ηL + ηV) and σ with average expanded (k = 2) uncertainties of (2.4 and 2.6) % agree very well with the few data available in the literature. The T-dependent behavior of the SLS results for σ can be described by a van der Waals-type surface tension equation in accordance with scaling theory. The experimental results for σ of CO2 served to evaluate the performance of equilibrium molecular dynamics (EMD) simulations in predicting its surface tension together with the phase behavior at T between (288.15 and 298.15) K. For this purpose, seven different force fields (FFs) employed from literature were applied, which provide all-atom or united-atom representations and involve rigid or flexible intramolecular potentials. It was found that a reliable representation of the vapor and liquid densities, vapor pressure, and σ near the critical point can only be realized using rigid FFs, all of which were not optimized against surface tension data.

Authors with CRIS profile

Neda Sanchouli Institute of Advanced Optical Technologies - Thermophysical Properties (AOT-TP) Andreas Paul Fröba Institute of Advanced Optical Technologies - Thermophysical Properties (AOT-TP) Thomas Manfred Koller Institute of Advanced Optical Technologies - Thermophysical Properties (AOT-TP)

Additional Organisation(s)

Erlangen Graduate School in Advanced Optical Technologies (SAOT)

Related research project(s)

Moderierende Effekte von Alkoholen auf die Grenzflächenspannung in mehrphasigen Systemen bestehend aus Kohlenstoffdioxid und organischen Lösungsmitteln Aug. 1, 2023 - July 31, 2026

How to cite

APA:

Sanchouli, N., Kankanamge, C.J., Fröba, A.P., & Koller, T.M. (2026). Surface tension and viscosity of carbon dioxide near the critical point using molecular dynamics simulations and surface light scattering. Fluid Phase Equilibria, 605. https://doi.org/10.1016/j.fluid.2026.114660

MLA:

Sanchouli, Neda, et al. "Surface tension and viscosity of carbon dioxide near the critical point using molecular dynamics simulations and surface light scattering." Fluid Phase Equilibria 605 (2026).

BibTeX: Download