1
|
Hrahsheh F, Jum'h I, Wilemski G. Second inflection point of supercooled water surface tension induced by hydrogen bonds: A molecular-dynamics study. J Chem Phys 2024; 160:114504. [PMID: 38506292 DOI: 10.1063/5.0185832] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2023] [Accepted: 02/26/2024] [Indexed: 03/21/2024] Open
Abstract
Surface tension of supercooled water is a fundamental property in various scientific processes. In this study, we perform molecular dynamics simulations with the TIP4P-2005 model to investigate the surface tension of supercooled water down to 220 K. Our results show a second inflection point (SIP) in the surface tension at temperature TSIP ≈ 267.5 ± 2.3 K. Using an extended IAPWS-E functional fit for the water surface tension, we calculate the surface excess internal-energy and entropy terms of the excess Helmholtz free energy. Similar to prior studies [Wang et al., Phys. Chem. Chem. Phys. 21, 3360 (2019); Gorfer et al., J. Chem. Phys. 158, 054503 (2023)], our results show that the surface tension is governed by two driving forces: a surface excess entropy change above the SIP and a surface excess internal-energy change below it. We study hydrogen-bonding near the SIP because it is the main cause of water's anomalous properties. With decreasing temperature, our results show that the entropy contribution to the surface tension reaches a maximum slightly below the SIP and then decreases. This is because the number of hydrogen bonds increases more slowly below the SIP. Moreover, the strengths and lifetimes of the hydrogen bonds also rise dramatically below the SIP, causing the internal-energy term to dominate the excess surface free energy. Thus, the SIP in the surface tension of supercooled TIP4P-2005 water is associated with an increase in the strengths and lifetimes of hydrogen bonds, along with a decrease in the formation rate (#/K) of new hydrogen bonds.
Collapse
Affiliation(s)
- Fawaz Hrahsheh
- Higher Colleges of Technology, ETS, MZWC, Abu Dhabi 25026, United Arab Emirates
| | - Inshad Jum'h
- School of Basic Sciences and Humanities, German Jordanian University, Amman 11180, Jordan
| | - Gerald Wilemski
- Department of Physics, Missouri University of Science and Technology, Rolla, Missouri 65409, USA
| |
Collapse
|
2
|
Chng JY, Sholl DS. Quantitative Simulations of Siloxane Adsorption in Metal-Organic Frameworks. ACS APPLIED MATERIALS & INTERFACES 2023; 15:37828-37836. [PMID: 37494552 PMCID: PMC10416143 DOI: 10.1021/acsami.3c07158] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2023] [Accepted: 07/12/2023] [Indexed: 07/28/2023]
Abstract
We present a transferable force field (FF) for simulating the bulk properties of linear and cyclic siloxanes and the adsorption of these species in metal-organic frameworks (MOFs). Unlike previous FFs for siloxanes, our FF accurately reproduces the vapor-liquid equilibria of each species in the bulk phase. The quality of our FF combined with the Universal Force Field using standard Lorentz-Berthelot combining rules for MOF atoms was assessed in a wide range of MOFs without open metal sites, showing good agreement with dispersion-corrected density functional theory calculations. Predictions with this FF show good agreement with the limited experimental data for siloxane adsorption in MOFs that is available. As an example of using the FF to predict adsorption properties in MOFs, we present simulations examining entropy effects in binary linear and cyclic siloxane mixture coadsorption in the large-pore MOF with structure code FOTNIN.
Collapse
Affiliation(s)
- Jia Yuan Chng
- School
of Chemical & Biomolecular Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0100, United States
| | - David S. Sholl
- School
of Chemical & Biomolecular Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0100, United States
- Oak
Ridge National Laboratory, Oak Ridge, Tennessee 37830, United States
| |
Collapse
|
3
|
Hrahsheh F, Wilemski G. Effects of molecular size and orientation on the interfacial properties and wetting behavior of water/ n-alkane systems: a molecular-dynamics study. Phys Chem Chem Phys 2023; 25:5808-5816. [PMID: 36744733 DOI: 10.1039/d2cp05735b] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Molecular dynamics simulations (MD) are performed to study the interfacial structure/tension and wetting behavior of water/n-alkane systems (water/nC5 to water/nC16 where nCx = CxH(2x + 2)). In particular, we study complete-to-partial wetting transitions by changing the n-alkane chain length (NC) at a constant temperature, T = 295 K. Simulations are carried out with a united-atom TraPPE model for n-alkanes and the TIP4P-2005 model of water. Simulation results are in excellent agreement with the initial spreading coefficients and contact angles calculated using experimental values of the surface and interfacial tensions. In addition, it has been determined that water/(nC5-nC7) and water/(nC8-nC16), respectively, exhibit complete and partial initial wetting modes. Simulations show that the interfacial structures of water/(nC5-nC7) are different from water/(nC8-nC16) systems. In the latter, water preferentially orients near the interface to increase the number of hydrogen bonds and the charge and mass densities. Moreover, the orientation of n-alkane molecules at water/(nC8-nC16) interfaces has a long-range persistence, resulting in layered structures that increase with NC. In addition, simulation results of the orientational order parameter Sz show alignment behavior of the n-alkane molecules with respect to the interfaces. Simulations predict that the central segments of n-alkane are strongly packed in the interfaces while the end segments (methyl groups) form smaller peaks in the outer edge of the layer. This observation confirms the "horseshoe" or "C-shaped" structure of n-alkane molecules in the water/n-alkane interfaces. At constant temperature, the interface widths of both water and the n-alkanes decrease with increasing n-alkane molecular length. These results suggest that increasing the n-alkane chain length affects the water/n-alkane interfacial properties in a manner similar to that of cooling.
Collapse
Affiliation(s)
- Fawaz Hrahsheh
- Higher Colleges of Technology, ETS, MZWC, Abu Dhabi, 58855, United Arab Emirates.
| | - Gerald Wilemski
- Department of Physics, Missouri University of Science and Technology, Rolla, MO 65409, USA.
| |
Collapse
|
4
|
Toutouni R, Kubelka J, Piri M. Quantitative Predictions and Experimental Validation of Liquid-Vapor Interfacial Tension in Binary and Ternary Mixtures of Alkanes Using Molecular Dynamics Simulations. J Phys Chem B 2023; 127:396-406. [PMID: 36563326 DOI: 10.1021/acs.jpcb.2c07748] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Liquid-vapor interfacial properties of alkane mixtures present a challenge for experimental determination, especially under conditions relevant to the energy industry processes. Molecular dynamics (MD) simulations can accurately predict interfacial tensions (IFTs) for complex alkane mixtures under virtually any conditions, thereby alleviating the need for difficult and costly experiments. MD simulations with the CHARMM force field and empirical corrections for the IFT and pressure were used to obtain the IFT for three binary mixtures of ethane (with n-pentane, n-hexane, and n-nonane) and a ternary system (ethane/n-butane/n-decane) under a variety of conditions. The results were thoroughly validated against experimental data from the literature, and new original IFT data were collected using the pendant drop method. The simulations are able to reproduce the experimental IFT to better than 0.5 mN/m or 5% on average and within 1 mN/m or 10% in the worst case. IFTs for the studied three binary and ternary alkane mixtures were predicted for wide ranges of conditions with no known experimental data. Finally, using the MD simulation data, the reliability of the widely used empirical parachor model for predicting IFT was reaffirmed, and the significance of the empirical parameters examined to establish an optimal balance between the accuracy and broad applicability of the model.
Collapse
Affiliation(s)
- Reihaneh Toutouni
- Center of Innovation for Flow through Porous Media, Department of Petroleum Engineering, University of Wyoming, Laramie, Wyoming82071, United States
| | - Jan Kubelka
- Center of Innovation for Flow through Porous Media, Department of Petroleum Engineering, University of Wyoming, Laramie, Wyoming82071, United States
| | - Mohammad Piri
- Center of Innovation for Flow through Porous Media, Department of Petroleum Engineering, University of Wyoming, Laramie, Wyoming82071, United States
| |
Collapse
|
5
|
Pan Z, Liu W, Yu L, Xie Z, Sun Q, Zhao P, Chen D, Fang W, Liu B. Resonance-Induced Reduction of Interfacial Tension of Water-Methane and Improvement of Methane Solubility in Water. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2022; 38:13594-13601. [PMID: 36299165 DOI: 10.1021/acs.langmuir.2c02392] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Molecular dynamics simulations were performed to study the effect of the periodic oscillating electric field on the interface between water and methane. We propose a new strategy that utilizes oscillating electric fields to reduce the interfacial tension (IFT) between water and methane and increase the solubility of methane in water simultaneously. These are attributed to the hydrogen bond resonance induced by an electric field with a frequency close to the natural frequency of the hydrogen bond. The resonance breaks the hydrogen bond network among water molecules to the maximum, which destroys the hydration shell and reduces the cohesive action of water, thus resulting in the decrease of IFT and the increase of methane solubility. As the frequency of the electric field is close to the optimum resonant frequency of hydrogen bonds, IFT decreases from 56.43 to 5.66 mN/m; water and methane are miscible because the solubility parameter of water reduces from 47.63 to 2.85 MPa1/2, which is close to that of methane (3.43 MPa1/2). Our results provide a new idea for reducing the water-gas IFT and improving the solubility of insoluble gas in water and theoretical guidance in the fields of natural gas exploitation, hydrate generation, and nanobubble nucleation.
Collapse
Affiliation(s)
- Zhiming Pan
- College of Science, China University of Petroleum (East China), Qingdao266580, China
| | - Wenyu Liu
- College of Science, China University of Petroleum (East China), Qingdao266580, China
| | - Leyang Yu
- College of Science, China University of Petroleum (East China), Qingdao266580, China
| | - Zhiyang Xie
- College of Science, China University of Petroleum (East China), Qingdao266580, China
| | - Qing Sun
- College of Science, China University of Petroleum (East China), Qingdao266580, China
| | - Peihe Zhao
- College of Science, China University of Petroleum (East China), Qingdao266580, China
| | - Dongmeng Chen
- College of Science, China University of Petroleum (East China), Qingdao266580, China
| | - Wenjing Fang
- College of Science, China University of Petroleum (East China), Qingdao266580, China
| | - Bing Liu
- College of Science, China University of Petroleum (East China), Qingdao266580, China
| |
Collapse
|
6
|
Morrow BH, Harrison JA. Interfacial Properties of Linear Alkane/Nitrogen Binary Mixtures: Molecular Dynamics Vapor-Liquid Equilibrium Simulations. J Phys Chem B 2022; 126:4379-4388. [PMID: 35666712 DOI: 10.1021/acs.jpcb.2c00688] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Molecular dynamics simulations were used to investigate the vapor-liquid equilibria (VLE) and interfacial properties of binary mixtures of N2 with either ethane, propane, n-decane, or n-dodecane. Alkanes and N2 were modeled by using the TraPPE-UA and Rivera force fields, respectively. The typically used Lorentz-Berthelot combining rules resulted in liquid phases that are too N2-rich compared to experiment. To improve the accuracy of VLE predictions, the hydrocarbon-nitrogen interactions were fine-tuned, and these improved parameters were used to investigate interfacial properties. Scaling the interaction strength between nitrogen and -CH3 and -CH2- groups by factors of 0.95 and 0.85, respectively, relative to the Lorentz-Berthelot value, was found to minimize error in pressure-composition phase diagrams. These scaling parameters gave excellent agreement with experimental phase diagrams for mixtures of N2 with ethane, propane, or n-dodecane over a range of state points. For ethane/N2 and n-decane/N2 mixtures, trends in surface tension as a function of temperature and pressure are correctly reproduced, although the simulated values are slightly too high compared to experimental values. To assess how the accuracy of hydrocarbon-N2 interaction strength impacts interfacial property predictions, we have compared density profiles and surface tension using several different scaling factors. Using the Lorentz-Berthelot combining rules rather than optimized parameters gave the same qualitative trends, although some quantitative results, such as liquid-phase N2 mole fraction, were found to differ by a factor of ∼1.5. Using the optimized interaction parameters, interfacial behavior was examined by calculating density and free energy profiles. Nitrogen molecules preferentially adsorb at the interfacial region between the liquid and vapor phases. This interfacial adsorption becomes less energetically favorable as either the temperature, pressure, or length of the alkane chain increases.
Collapse
Affiliation(s)
- Brian H Morrow
- Department of Chemistry, United States Naval Academy, Annapolis, Maryland 21402, United States
| | - Judith A Harrison
- Department of Chemistry, United States Naval Academy, Annapolis, Maryland 21402, United States
| |
Collapse
|
7
|
Toutouni R, Kubelka J, Piri M. Liquid–Vapor Interfacial Tension in Alkane Mixtures: Improving Predictive Capabilities of Molecular Dynamics Simulations. J Phys Chem B 2022; 126:1136-1146. [DOI: 10.1021/acs.jpcb.1c09122] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Reihaneh Toutouni
- Center of Innovation for Flow through Porous Media, Department of Petroleum Engineering, University of Wyoming, Laramie, Wyoming 82071, United States
| | - Jan Kubelka
- Center of Innovation for Flow through Porous Media, Department of Petroleum Engineering, University of Wyoming, Laramie, Wyoming 82071, United States
| | - Mohammad Piri
- Center of Innovation for Flow through Porous Media, Department of Petroleum Engineering, University of Wyoming, Laramie, Wyoming 82071, United States
| |
Collapse
|