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Saito T, Kubo M, Tsukada T, Shoji E, Kikugawa G, Surblys D, Kubo M. Molecular dynamics simulations for interfacial structure and affinity between carboxylic acid-modified Al2O3 and polymer melts. J Chem Phys 2023; 159:164708. [PMID: 37888762 DOI: 10.1063/5.0169721] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Accepted: 10/10/2023] [Indexed: 10/28/2023] Open
Abstract
Controlling the dispersion state of nanoparticles in a polymer matrix is necessary to produce polymer nanocomposites. The surface modification of nanoparticles is used to enable their dispersion in polymers. Moreover, molecular dynamics (MD) simulations are useful for revealing the interfacial properties between nanoparticles and polymers to aid in the design of materials. In this study, the effect of surface coverage, modifier length, and polymer species on the interfacial structure and affinity between surface-modified Al2O3 and polymer melts were investigated using all-atom MD simulations. Hexanoic, decanoic, and tetradecanoic acids were used as surface modifiers, and polypropylene (PP), polystyrene (PS), and poly (methyl methacrylate) (PMMA) were used as polymers. The work of adhesion Wadh and the work of immersion Wimm were selected as quantitative measures of affinity. Wadh was calculated using the phantom-wall approach, and Wimm was calculated by simply subtracting the surface tension of polymers γL from Wadh. The results showed that Wadh and Wimm were improved by surface modification with low coverage, owing to a good penetration of the polymer. The effect of modifier length on Wadh and Wimm was small. Whereas Wadh increased in the following order: PP < PS < PMMA, Wimm increased as follows: PMMA < PS < PP. Finally, the trend of Wadh and Wimm was organized using the Flory-Huggins interaction parameter χ between the modifier and the polymer. This study demonstrates that the interfacial affinity can be improved by tuning the surface coverage and modifier species depending on the polymer matrix.
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Affiliation(s)
- Takamasa Saito
- Department of Chemical Engineering, Tohoku University, 6-6-07 Aramaki, Aoba-ku, Sendai, Miyagi 980-8579, Japan
| | - Masaki Kubo
- Department of Chemical Engineering, Tohoku University, 6-6-07 Aramaki, Aoba-ku, Sendai, Miyagi 980-8579, Japan
| | - Takao Tsukada
- New Industry Creation Hatchery Center, Tohoku University, 6-6-10 Aramaki, Aoba-ku, Sendai, Miyagi 980-8579, Japan
| | - Eita Shoji
- Department of Mechanical Systems Engineering, Tohoku University, 6-6-01 Aramaki, Aoba-ku, Sendai, Miyagi 980-8579, Japan
| | - Gota Kikugawa
- Institute of Fluid Science, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, Miyagi 980-8577, Japan
| | - Donatas Surblys
- Institute of Fluid Science, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, Miyagi 980-8577, Japan
| | - Momoji Kubo
- Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, Miyagi 980-8577, Japan
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Neupane P, Wilemski G. Molecular dynamics study of wetting of alkanes on water: from high temperature to the supercooled region and the influence of second inflection points of interfacial tensions. Phys Chem Chem Phys 2021; 23:14465-14476. [PMID: 34184020 DOI: 10.1039/d1cp01108a] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
To explore the wetting behavior of alkanes on bulk water interfaces, molecular dynamics (MD) simulations were carried out for united-atom PYS alkane models, and for SPC/E and TIP4P/2005 water models over a wide temperature range. The MD results at each temperature were used to find (1) the surface tension of the alkanes (octane, nonane) and water, and (2) the interfacial tensions of the alkane-water systems. These quantities were then used to calculate the spreading coefficient (S) and contact angle (θc) for each alkane on water. At higher temperatures, the contact angle of octane and nonane on water is found to behave in accord with conventional expectations, i.e., it decreases with increasing temperature for both water models as each system approaches the usual high-temperature transition to perfect wetting. At lower temperatures, we found an unusual temperature dependence of S and θc for each PYS alkane on SPC/E water. In contrast to conventional expectations, θc decreases with a decrease in the temperature. For octane-SPC/E water, this unusual behavior of θc occurs due to the presence of second inflection points (SIP) in the vapor-water and the octane-water interfacial tensions, whereas the SIP effect is much less important for the nonane-water system. The unusual temperature dependence of θc observed for nonane on SPC/E water is also found for nonane on TIP4P/2005 water. On the other hand, such unusual wetting behavior has not been observed in the PYS octane-TIP4P/2005 water system, except possibly for the two lowest temperatures studied.
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Affiliation(s)
- Pauf Neupane
- Department of Physics, Missouri University of Science and Technology, Rolla, MO 65409, USA.
| | - Gerald Wilemski
- Department of Physics, Missouri University of Science and Technology, Rolla, MO 65409, USA.
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Zhang L, Lu X, Liu X, Li Q, Cheng Y, Hou Q. Molecular dynamics simulation of CO 2-switchable surfactant regulated reversible emulsification/demulsification processes of a dodecane-saline system. Phys Chem Chem Phys 2020; 22:23574-23585. [PMID: 33057504 DOI: 10.1039/d0cp03904g] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
CO2-Switchable surfactants are of great potential in a wide range of industrial applications related to their ability to stabilize and destabilize emulsions upon command. Molecular dynamics simulations have been performed to reveal the fundamental mechanism of the reversible emulsification/demulsification processes of a dodecane-saline system by a CO2-switchable surfactant that switches between active (i.e., N'-dodecyl-N,N-dimethylacetamidinium (DMAAH+)) and inactive (i.e., N'-dodecyl-N,N-dimethylacetamidine (DMAA)) forms. The density profiles indicate that DMAAH+ could increase the oil-water interfacial thickness to a greater extent compared to DMAA. DMAAH+ could sharply reduce the interfacial tension of the dodecane-saline system, while DMAA only exhibits a limited decrease, which is in accordance with the experimental observation that DMAAH+/DMAA can reversibly emulsify/demulsify alkane-water systems. Our simulations showed that both the number and lifetime of hydrogen bonds (HBs) between DMAA and water are almost equal to those between DMAAH+ and water. In DMAA, the N atom connecting with the alkyl tail acted as a HB acceptor, while the N atom attached by a proton in DMAAH+ acted as a HB donor. Furthermore, the HBs between DMAAH+ and HCO3- at the interfaces are relatively limited. Hence, it is deduced that the HBs are insufficient to achieve the CO2-switchability of DMAA/DMAAH+. The Lennard Jones and coulombic potentials between DMAA/DMAAH+ and other species show that the coulombic potentials between DMAAH+ and water or anions (i.e., Cl- and HCO3-) sharply decrease with the increase of DMAAH+ and are much lower than those in models with DMAA. The enhanced coulombic interactions between DMAAH+ and anions lead to a remarkable reduction in interfacial tension and the emulsification of the alkane-saline system. Therefore, coulombic interactions are of crucial importance to the reversible emulsification/demulsification processes regulated by CO2-switchable surfactants, namely DMAAH+/DMAA.
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Affiliation(s)
- Lihu Zhang
- State Key Laboratory for Ore Deposits Research, School of Earth Sciences and Engineering, Nanjing University, Nanjing, Jiangsu 210023, P. R. China.
| | - Xiancai Lu
- State Key Laboratory for Ore Deposits Research, School of Earth Sciences and Engineering, Nanjing University, Nanjing, Jiangsu 210023, P. R. China. and Key Lab of Surficial Geochemistry of Ministry of Education, School of Earth Sciences and Engineering, Nanjing University, Nanjing, Jiangsu 210023, P. R. China
| | - Xiandong Liu
- State Key Laboratory for Ore Deposits Research, School of Earth Sciences and Engineering, Nanjing University, Nanjing, Jiangsu 210023, P. R. China.
| | - Qin Li
- State Key Laboratory for Ore Deposits Research, School of Earth Sciences and Engineering, Nanjing University, Nanjing, Jiangsu 210023, P. R. China.
| | - Yongxian Cheng
- State Key Laboratory for Ore Deposits Research, School of Earth Sciences and Engineering, Nanjing University, Nanjing, Jiangsu 210023, P. R. China.
| | - Qingfeng Hou
- State Key Laboratory of Enhanced Oil Recovery, Research Institute of Petroleum Exploration and Development, China National Petroleum Corporation (CNPC), Beijing 100083, P. R. China
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Papavasileiou KD, Peristeras LD, Bick A, Economou IG. Molecular Dynamics Simulation of Pure n-Alkanes and Their Mixtures at Elevated Temperatures Using Atomistic and Coarse-Grained Force Fields. J Phys Chem B 2019; 123:6229-6243. [PMID: 31251061 DOI: 10.1021/acs.jpcb.9b02840] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The properties of higher n-alkanes and their mixtures is a topic of significant interest for the oil and chemical industry. However, the experimental data at high temperatures are scarce. The present study focuses on simulating n-dodecane, n-octacosane, their binary mixture at a n-dodecane mole fraction of 0.3, and a model mixture of the commercially available hydrocarbon wax SX-70 to evaluate the performance of several force fields on the reproduction of properties such as liquid densities, surface tension, and viscosities. Molecular dynamics simulations over a broad temperature range from 323.15 to 573.15 K were employed in examining a broad set of atomistic molecular models assessed for the reproduction of experimental data. The well-established united atom TraPPE (TraPPE-UA) was compared against the all atom optimized potentials for liquid simulations (OPLS) reparametrization for long n-alkanes, L-OPLS, as well as Lipid14 and MARTINI force fields. All models qualitatively reproduce the temperature dependence of the aforementioned properties, but TraPPE-UA was found to reproduce liquid densities most accurately and consistently over the entire temperature range. TraPPE-UA and MARTINI were very successful in reproducing surface tensions, and L-OPLS was found to be the most accurate in reproducing the measured viscosities as compared to the other models. Our simulations show that these widely used force fields originating from the world of biomolecular simulations are suitable candidates in the study of n-alkane properties, both in the pure and mixture states.
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Affiliation(s)
- Konstantinos D Papavasileiou
- Institute of Nanoscience and Nanotechnology, Molecular Thermodynamics and Modelling of Materials Laboratory , National Center for Scientific Research "Demokritos" , Aghia Paraskevi, Attikis, GR-15310 Athens , Greece.,Scienomics SARL , 16 rue de l'Arcade , 75008 , Paris , France
| | - Loukas D Peristeras
- Institute of Nanoscience and Nanotechnology, Molecular Thermodynamics and Modelling of Materials Laboratory , National Center for Scientific Research "Demokritos" , Aghia Paraskevi, Attikis, GR-15310 Athens , Greece
| | - Andreas Bick
- Scienomics SARL , 16 rue de l'Arcade , 75008 , Paris , France
| | - Ioannis G Economou
- Institute of Nanoscience and Nanotechnology, Molecular Thermodynamics and Modelling of Materials Laboratory , National Center for Scientific Research "Demokritos" , Aghia Paraskevi, Attikis, GR-15310 Athens , Greece.,Chemical Engineering Program , Texas A&M University at Qatar , Education City , P.O. Box 23874, Doha , Qatar
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The Water-Alkane Interface at Various NaCl Salt Concentrations: A Molecular Dynamics Study of the Readily Available Force Fields. Sci Rep 2018; 8:352. [PMID: 29321556 PMCID: PMC5762912 DOI: 10.1038/s41598-017-18633-y] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2017] [Accepted: 12/14/2017] [Indexed: 11/11/2022] Open
Abstract
In this study, classical molecular dynamic simulations have been used to examine the molecular properties of the water-alkane interface at various NaCl salt concentrations (up to 3.0 mol/kg). A variety of different force field combinations have been compared against experimental surface/interfacial tension values for the water-vapour, decane-vapour and water-decane interfaces. Six different force fields for water (SPC, SPC/E, TIP3P, TIP3Pcharmm, TIP4P & TIP4P2005), and three further force fields for alkane (TraPPE-UA, CGenFF & OPLS) have been compared to experimental data. CGenFF, OPLS-AA and TraPPE-UA all accurately reproduce the interfacial properties of decane. The TIP4P2005 (four-point) water model is shown to be the most accurate water model for predicting the interfacial properties of water. The SPC/E water model is the best three-point parameterisation of water for this purpose. The CGenFF and TraPPE parameterisations of oil accurately reproduce the interfacial tension with water using either the TIP4P2005 or SPC/E water model. The salinity dependence on surface/interfacial tension is accurately captured using the Smith & Dang parameterisation of NaCl. We observe that the Smith & Dang model slightly overestimates the surface/interfacial tensions at higher salinities (>1.5 mol/kg). This is ascribed to an overestimation of the ion exclusion at the interface.
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Brumby PE, Wensink HH, Haslam AJ, Jackson G. Structure and Interfacial Tension of a Hard-Rod Fluid in Planar Confinement. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2017; 33:11754-11770. [PMID: 28885848 DOI: 10.1021/acs.langmuir.7b02254] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The structural properties and interfacial tension of a fluid of rodlike hard-spherocylinder particles in contact with hard structureless flat walls are studied by means of Monte Carlo simulation. The calculated surface tension between the rod fluid and the substrate is characterized by a nonmonotonic trend as a function of the bulk concentration (density) over the range of isotropic bulk concentrations. As suggested by earlier theoretical studies, a surface-ordering scenario is confirmed by our simulations: the local orientational order close to the wall changes from uniaxial to biaxial nematic when the bulk concentration reaches about 85% of the value at the onset of the isotropic-nematic phase transition. The surface ordering coincides with a wetting transition whereby the hard wall is wetted by a nematic film. Accurate values of the fluid-solid surface tension, the adsorption, and the average particle-wall contact distance are reported (over a broad range of densities into the dense nematic region for the first time), which can serve as a useful benchmark for future theoretical and experimental studies on confined rod fluids. The simulation data are supplemented with predictions from second-virial density functional theory, which are in good qualitative agreement with the simulation results.
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Affiliation(s)
- Paul E Brumby
- Department of Mechanical Engineering, Keio University , 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522, Japan
| | - Henricus H Wensink
- Laboratoire de Physique des Solides, Université Paris Sud & CNRS , 91405 Orsay Cedex, France
| | - Andrew J Haslam
- Department of Chemical Engineering and Qatar Carbonates and Carbon Storage Research Centre, Imperial College London , South Kensington Campus, London SW7 2AZ, United Kingdom
| | - George Jackson
- Department of Chemical Engineering and Qatar Carbonates and Carbon Storage Research Centre, Imperial College London , South Kensington Campus, London SW7 2AZ, United Kingdom
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7
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Gyawali G, Sternfield S, Kumar R, Rick SW. Coarse-Grained Models of Aqueous and Pure Liquid Alkanes. J Chem Theory Comput 2017. [DOI: 10.1021/acs.jctc.7b00389] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Gaurav Gyawali
- Department of Chemistry, University of New Orleans, New Orleans, Louisiana 70148, United States
| | - Samuel Sternfield
- Department of Chemistry, University of New Orleans, New Orleans, Louisiana 70148, United States
| | - Revati Kumar
- Department
of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70808, United States
| | - Steven W. Rick
- Department of Chemistry, University of New Orleans, New Orleans, Louisiana 70148, United States
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8
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Bringas G, Navarro-Santos P, López-Rendón R, López-Lemus J, Bresme F. Molecular dynamics simulations of 2-(dimethylamino)ethanol (DMEA). J Phys Chem B 2015; 119:5035-46. [PMID: 25799889 DOI: 10.1021/jp509577x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We develop a multipurpose force field to investigate the properties of the condensed phases of 2-(dimethylamino)ethanol (DMEA). We use ab initio computations at the HF/6-311++G(2d,2p) level to derive partial charges, obtain force constants, and compute the electrostatic potential of the DMEA. We find that the HF predictions for the dipole moment are in excellent agreement with the experimental result (2.6 D). The computations also show the strong preference of DMEA to form intramolecular hydrogen bonds between the hydrogen in the alcohol group and nitrogen. We have tested the accuracy of our force field by computing coexistence and interfacial properties as well as thermal conductivities in wide range of thermodynamic states. In all these instances we find excellent agreement with the available experimental data. We have further investigated the structure of the liquid by computing pair correlations. Our results indicate a clear preference for DMEA to form low-dimensional structures, such as linear and bifurcated chains, which are driven by the association of the DMEA molecules via the alcohol group. Overall, our force field provides a good basis to compute the bulk and interfacial properties of DMEA.
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Affiliation(s)
| | - Pedro Navarro-Santos
- §Facultad de Ingenería en Tecnología de la Madera, Universidad Michoacana de San Nicolás de Hidalgo, Morelia, CP 58000, México
| | | | - Jorge López-Lemus
- ∥Department of Chemistry, Imperial College London, London SW7 2AZ, United Kingdom
| | - Fernando Bresme
- ∥Department of Chemistry, Imperial College London, London SW7 2AZ, United Kingdom.,⊥Department of Chemistry, Norwegian University of Science and Technology, Trondheim, Norway
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Ghobadi AF, Elliott JR. Adapting SAFT-γ perturbation theory to site-based molecular dynamics simulation. II. Confined fluids and vapor-liquid interfaces. J Chem Phys 2014; 141:024708. [DOI: 10.1063/1.4886398] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
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10
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Hernandez DA, Domínguez H. Structural and thermodynamic behavior of alkane chains at the liquid/vapor interface. J Chem Phys 2013; 138:134702. [DOI: 10.1063/1.4798346] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
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11
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Zubillaga RA, Labastida A, Cruz B, Martínez JC, Sánchez E, Alejandre J. Surface Tension of Organic Liquids Using the OPLS/AA Force Field. J Chem Theory Comput 2013; 9:1611-5. [DOI: 10.1021/ct300976t] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Rafael A. Zubillaga
- Departamento de Química,
Universidad Autónoma Metropolitana-Iztapalapa, Av. San Rafael
Atlixco 186, Col. Vicentina, 09340 México D.F., México
| | - Ariana Labastida
- Departamento de Química,
Universidad Autónoma Metropolitana-Iztapalapa, Av. San Rafael
Atlixco 186, Col. Vicentina, 09340 México D.F., México
| | - Bibiana Cruz
- Departamento de Química,
Universidad Autónoma Metropolitana-Iztapalapa, Av. San Rafael
Atlixco 186, Col. Vicentina, 09340 México D.F., México
| | - Juan Carlos Martínez
- Departamento de Química,
Universidad Autónoma Metropolitana-Iztapalapa, Av. San Rafael
Atlixco 186, Col. Vicentina, 09340 México D.F., México
| | - Enrique Sánchez
- Colegio de Ciencia y Tecnología,
Universidad Autónoma de la Ciudad de México, Plantel
Casa Libertad, Calzada Ermita Iztapalapa s/n, 09620 México
D. F., México
| | - José Alejandre
- Departamento de Química,
Universidad Autónoma Metropolitana-Iztapalapa, Av. San Rafael
Atlixco 186, Col. Vicentina, 09340 México D.F., México
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WANG JUN, ZENG XIAOCHENG. COMPUTER SIMULATION OF LIQUID–VAPOR INTERFACIAL TENSION: LENNARD-JONES FLUID AND WATER REVISITED. JOURNAL OF THEORETICAL & COMPUTATIONAL CHEMISTRY 2011. [DOI: 10.1142/s0219633609005027] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
We review several commonly used simulation methods for computing liquid–vapor surface tension and associated theoretical treatments of the long-range correction for inhomogeneous systems. Prototype model systems considered in this review are the Lennard-Jones (LJ) fluid and the SPC/E model water. In addition, we examine a variety of factors that can affect calculation of the surface tension γ via the mechanical approach (i.e. using either KB or IK method). It is found that for the LJ fluid, the size of simulation box and the number of particles in the system can have notable effects on the computed surface tension. For SPC/E water, the Ewald parameters can influence computed surface tensions (γ) as well, e.g., very small Ewald parameters tend to overestimate γ. It is also found that the IK method consistently gives γ that are 0.6 - 0.9 mN/m greater than γ computed based on the KB method. When computing the first reciprocal–space contribution to the surface tension, the Ghoufi's strategy gives rise to more sensible profile of pressure difference PN(z)-PT(z) than the Alejandre's strategy although both strategies result in nearly the same average surface tension through the integration of PN(z)-PT(z).
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Affiliation(s)
- JUN WANG
- Department of Chemistry, University of Nebraska-Lincoln, Lincoln, Nebraska 68588, USA
| | - XIAO CHENG ZENG
- Department of Chemistry, University of Nebraska-Lincoln, Lincoln, Nebraska 68588, USA
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Müller EA, Mejía A. Comparison of united-atom potentials for the simulation of vapor-liquid equilibria and interfacial properties of long-chain n-alkanes up to n-C100. J Phys Chem B 2011; 115:12822-34. [PMID: 21932822 DOI: 10.1021/jp203236q] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Canonical ensemble molecular dynamics (MD) simulations are reported which compute both the vapor-liquid equilibrium properties (vapor pressure and liquid and vapor densities) and the interfacial properties (density profiles, interfacial tensions, entropy and enthalpy of surface formation) of four long-chained n-alkanes: n-decane (n-C(10)), n-eicosane (n-C(20)), n-hexacontane (n-C(60)), and n-decacontane (n-C(100)). Three of the most commonly employed united-atom (UA) force fields for alkanes (SKS: Smit, B.; Karaborni, S.; Siepmann, J. I. J. Chem. Phys. 1995,102, 2126-2140; J. Chem. Phys. 1998,109, 352; NERD: Nath, S. K.; Escobedo, F. A.; de Pablo, J. J. J. Chem. Phys. 1998, 108, 9905-9911; and TraPPE: Martin M. G.; Siepmann, J. I. J. Phys. Chem. B1998, 102, 2569-2577.) are critically appraised. The computed results have been compared to the available experimental data and those fitted using the square gradient theory (SGT). In the latter approach, the Lennard-Jones chain equation of state (EoS), appropriately parametrized for long hydrocarbons, is used to model the homogeneous bulk phase Helmholtz energy. The MD results for phase equilibria of n-decane and n-eicosane exhibit sensible agreement both to the experimental data and EoS correlation for all potentials tested, with the TraPPE potential showing the lowest deviations. However, as the molecular chain increases to n-hexacontane and n-decacontane, the reliability of the UA potentials decreases, showing notorious subpredictions of both saturated liquid density and vapor pressure. Based on the recommended data and EoS results for the heaviest hydrocarbons, it is possible to attest, that in this extreme, the TraPPE potential shows the lowest liquid density deviations. The low absolute values of the vapor pressure preclude the discrimination among the three UA potentials studied. On the other hand, interfacial properties are very sensitive to the type of UA potential thus allowing a differentiation of the potentials. Comparing the interfacial tension MD results to the available experimental data and SGT results, the TraPPE model exhibits the lowest deviations for all hydrocarbons.
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Affiliation(s)
- Erich A Müller
- Department of Chemical Engineering, Imperial College London, South Kensington Campus, London, United Kingdom.
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14
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Bresme F, Chacón E, Tarazona P. Force-field dependence on the interfacial structure of oil–water interfaces. Mol Phys 2010. [DOI: 10.1080/00268976.2010.496376] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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15
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Amat MA, Rutledge GC. Liquid-vapor equilibria and interfacial properties of n-alkanes and perfluoroalkanes by molecular simulation. J Chem Phys 2010; 132:114704. [DOI: 10.1063/1.3356219] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
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16
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Khedr MB, Osman S, Al Busaidi M. Surface tension, shear viscosity and isothermal compressibility of liquid C60along the liquid-vapour coexistence. Mol Phys 2009. [DOI: 10.1080/00268970902881979] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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