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Kurakin S, Ivankov O, Skoi V, Kuklin A, Uhríková D, Kučerka N. Cations Do Not Alter the Membrane Structure of POPC—A Lipid With an Intermediate Area. Front Mol Biosci 2022; 9:926591. [PMID: 35898308 PMCID: PMC9312375 DOI: 10.3389/fmolb.2022.926591] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Accepted: 06/07/2022] [Indexed: 12/02/2022] Open
Abstract
Combining small-angle neutron scattering (SANS), small-angle X-ray scattering (SAXS), and densitometric measurements, we have studied the interactions of the divalent cations Ca2+ and Mg2+ with the lipid vesicles prepared of a mixed-chain palmitoyl-oleoyl-phosphatidylcholine (POPC) at 25°C. The structural parameters of the POPC bilayer, such as the bilayer thickness, lateral area, and volume per lipid, displayed no changes upon the ion addition at concentrations up to 30 mM and minor changes at > 30 mM Ca2+ and Mg2+, while some decrease in the vesicle radius was observed over the entire concentration range studied. This examination allows us to validate the concept of lipid–ion interactions governed by the area per lipid suggested previously and to propose the mixed mode of those interactions that emerge in the POPC vesicles. We speculate that the average area per POPC lipid that corresponds to the cutoff length of lipid–ion interactions generates an equal but opposite impact on ion bridges and separate lipid–ion pairs. As a result of the dynamic equilibrium, the overall structural properties of bilayers are not affected. As the molecular mechanism proposed is affected by the structural properties of a particular lipid, it might help us to understand the fundamentals of processes occurring in complex multicomponent membrane systems.
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Affiliation(s)
- Sergei Kurakin
- Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research, Dubna, Russia
- Institute of Physics, Kazan Federal University, Kazan, Russia
| | - Oleksandr Ivankov
- Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research, Dubna, Russia
| | - Vadim Skoi
- Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research, Dubna, Russia
- Moscow Institute of Physics and Technology, Dolgoprudnyi, Russia
| | - Alexander Kuklin
- Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research, Dubna, Russia
- Moscow Institute of Physics and Technology, Dolgoprudnyi, Russia
| | - Daniela Uhríková
- Department of Physical Chemistry of Drugs, Faculty of Pharmacy, Comenius University Bratislava, Bratislava, Slovakia
| | - Norbert Kučerka
- Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research, Dubna, Russia
- Department of Physical Chemistry of Drugs, Faculty of Pharmacy, Comenius University Bratislava, Bratislava, Slovakia
- *Correspondence: Norbert Kučerka,
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2
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Precipitation Behavior of Salts in Supercritical Water: Experiments and Molecular Dynamics Simulations. Processes (Basel) 2022. [DOI: 10.3390/pr10020423] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Supercritical water desalination (SCWD) shows great potential in the treatment of high-salt wastewater with zero liquid discharge. To investigate the salt precipitation behavior and mechanism in supercritical water, experiments and molecular dynamics simulations (MDs) were used to study the salting-out process of different salts in supercritical water. The equilibrium concentrations of NaCl, KCl, CaCl2, Na2SO4, and Na2CO3 in supercritical water were experimentally measured. When the temperature exceeded 693 K, the salt equilibrium concentration measured in the experiment was less than 130 mg/L. The solubility decreased in the order of KCl > NaCl > CaCl2 > Na2SO4 > Na2CO3. To elucidate the effects of different cations and anions in supercritical water on salt dissolution and precipitation behavior, the potential energy, radial distribution function (RDF) and coordination number in the system were obtained via molecular dynamics simulation. Experimental and MD results showed that salt solubility has significant positive correlation with systemic potential energy and hydration number. MD results indicated that a small ionic radius, large ionic charge, and low hydration coordination number are favorable for inorganic salts to precipitate and crystallize since these factors can strengthen the interaction between free ions and salt clusters. Moreover, due to the formation of multilayer coordination structure, polyatomic ions can achieve a lower equilibrium concentration than that of the corresponding monatomic ions.
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3
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Park SJ, Narvaez WA, Schwartz BJ. How Water-Ion Interactions Control the Formation of Hydrated Electron:Sodium Cation Contact Pairs. J Phys Chem B 2021; 125:13027-13040. [PMID: 34806385 DOI: 10.1021/acs.jpcb.1c08256] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Although solvated electrons are a perennial subject of interest, relatively little attention has been paid to the way they behave in aqueous electrolytes. Experimentally, it is known that the hydrated electron's (eaq-) absorption spectrum shifts to the blue in the presence of salts, and the magnitude of the shift depends on the ion concentration and the identities of both the cation and anion. Does the blue-shift result from some type of dielectric effect from the bulk electrolyte, or are there specific interactions between the hydrated electron and ions in solution? Previous work has suggested that eaq- forms contact pairs with aqueous ions such as Na+, leading to the question of what controls the stability of such contact pairs and their possible connection to the observed spectroscopy. In this work, we use mixed quantum/classical simulations to examine the nature of Na+:e- contact pairs in water, using a novel method for quantum umbrella sampling to construct eaq--ion potentials of mean force (PMF). We find that the nature of the contact pair PMF depends sensitively on the choice of the classical interactions used to describe the Na+-water interactions. When the ion-water interactions are slightly stronger, the corresponding cation:e- contact pairs form at longer distances and become free energetically less stable. We show that this is because there is a delicate balance between solvation of the cation, solvation of eaq- and the direct electronic interaction between the cation and the electron, so that small changes in this balance lead to large changes in the formation and stability of e--ion contact pairs. In particular, strengthening the ion-water interactions helps to maintain a favorable local solvation environment around Na+, which in turn forces water molecules in the first solvation shell of the cation to be unfavorably oriented toward the electron in a contact pair; stronger solvation of the cation also reduces the electronic overlap of eaq- with Na+. We also find that the calculated spectra of different models of Na+:e- contact pairs do not shift monotonically with cation-electron distance, and that the calculated spectral shifts are about an order of magnitude larger than experiment, suggesting that isolated contact pairs are not the sole explanation for the blue-shift of the hydrated electron's spectrum in the presence of electrolytes.
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Affiliation(s)
- Sanghyun J Park
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, California 90095-1569, United States
| | - Wilberth A Narvaez
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, California 90095-1569, United States
| | - Benjamin J Schwartz
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, California 90095-1569, United States
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4
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Prelesnik J, Maibaum L. Effects of Salts on the Solvation of Hydrophobic Objects in Water. J Phys Chem B 2021; 125:11036-11043. [PMID: 34583505 DOI: 10.1021/acs.jpcb.1c06833] [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
The solvation of large, hydrophobic objects in water is facilitated by the formation of a low-density region surrounding the solute that is separated from the bulk liquid by an interface, which has a structure that resembles that between a liquid and its vapor. We study the effect of dissolved sodium chloride on the thermodynamics of solvation and on the solvent structure surrounding hydrophobic solutes in the size regime where this interface is not yet fully formed. Using biased Molecular Dynamics computer simulations, we calculate solvation free energies and orientational distributions of water molecules at different salt concentrations and solute sizes. We find that while the effects of sodium chloride on thermodynamic properties are small, the ions' response to the presence of a hydrophobic solute differs significantly from that of the water. Our findings provide mechanistic insight into how our understanding of hydrophobic solvation in water can be extended to electrolyte solutions.
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Affiliation(s)
- Jesse Prelesnik
- Department of Chemistry, University of Washington, Seattle, Washington 98195, United States
| | - Lutz Maibaum
- Department of Chemistry, University of Washington, Seattle, Washington 98195, United States
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5
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Rjiba A, El Hog S, Jelassi J, Garbouj H, Dorbez-Sridi R. Local structure in lithium chloride solution: a Monte-Carlo simulation study. MOLECULAR SIMULATION 2021. [DOI: 10.1080/08927022.2021.1956684] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Affiliation(s)
- Abdelkarim Rjiba
- Laboratoire Physico-Chimie des Matériaux, Université de Monastir, Monastir, Tunisie
| | - Sahbi El Hog
- Laboratoire de la Matière Condensée et des Nanosciences (LMCN), Université de Monastir, Monastir, Tunisie
| | - Jawhar Jelassi
- Laboratoire Physico-Chimie des Matériaux, Université de Monastir, Monastir, Tunisie
| | - Hedi Garbouj
- Laboratoire de la Matière Condensée et des Nanosciences (LMCN), Université de Monastir, Monastir, Tunisie
| | - Rachida Dorbez-Sridi
- Laboratoire Physico-Chimie des Matériaux, Université de Monastir, Monastir, Tunisie
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6
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Marin TW, Janik I, Bartels DM, Chipman DM. Failure of molecular dynamics to provide appropriate structures for quantum mechanical description of the aqueous chloride ion charge-transfer-to-solvent ultraviolet spectrum. Phys Chem Chem Phys 2021; 23:9109-9120. [PMID: 33885094 DOI: 10.1039/d1cp00930c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The lowest band in the charge-transfer-to-solvent ultraviolet absorption spectrum of aqueous chloride ion is studied by experiment and computation. Interestingly, the experiments indicate that at concentrations up to at least 0.25 M, where calculations indicate ion pairing to be significant, there is no notable effect of ionic strength on the spectrum. The experimental spectra are fitted to aid comparison with computations. Classical molecular dynamic simulations are carried out on dilute aqueous Cl-, Na+, and NaCl, producing radial distribution functions in reasonable agreement with experiment and, for NaCl, clear evidence of ion pairing. Clusters are extracted from the simulations for quantum mechanical excited state calculations. Accurate ab initio coupled-cluster benchmark calculations on a small number of representative clusters are carried out and used to identify and validate an efficient protocol based on time-dependent density functional theory. The latter is used to carry out quantum mechanical calculations on thousands of clusters. The resulting computed spectrum is in excellent agreement with experiment for the peak position, with little influence from ion pairing, but is in qualitative disagreement on the width, being only about half as wide. It is concluded that simulation by classical molecular dynamics fails to provide an adequate variety of structures to explain the experimental CTTS spectrum of aqueous Cl-.
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Affiliation(s)
- Timothy W Marin
- Department of Physical Sciences, Benedictine University, 5700 College Rd, Lisle, IL 60532, USA
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7
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Saric D, Kohns M, Vrabec J. Dielectric constant and density of aqueous alkali halide solutions by molecular dynamics: A force field assessment. J Chem Phys 2020; 152:164502. [PMID: 32357782 DOI: 10.1063/1.5144991] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
The concentration dependence of the dielectric constant and the density of 11 aqueous alkali halide solutions (LiCl, NaCl, KCl, RbCl, CsCl, LiI, NaI, KI, CsI, KF, and CsF) is investigated by molecular simulation. Predictions using eight non-polarizable ion force fields combined with the TIP4P/ε water model are compared to experimental data. The influence of the water model and the temperature on the results for the NaCl brine are also addressed. The TIP4P/ε water model improves the accuracy of dielectric constant predictions compared to the SPC/E water model. The solution density is predicted well by most ion models. Almost all ion force fields qualitatively capture the decline of the dielectric constant with the increase of concentration for all solutions and with the increase of temperature for NaCl brine. However, the sampled dielectric constant is mostly in poor quantitative agreement with experimental data. These results are related to the microscopic solution structure, ion pairing, and ultimately the force field parameters. Ion force fields with excessive contact ion pairing and precipitation below the experimental solubility limit generally yield higher dielectric constant values. An adequate reproduction of the experimental solubility limit should therefore be a prerequisite for further investigations of the dielectric constant of aqueous electrolyte solutions by molecular simulation.
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Affiliation(s)
- Denis Saric
- Thermodynamics and Energy Technology, University of Paderborn, 33098 Paderborn, Germany
| | - Maximilian Kohns
- Laboratory of Engineering Thermodynamics, Technische Universität Kaiserslautern, 67633 Kaiserslautern, Germany
| | - Jadran Vrabec
- Thermodynamics and Process Engineering, Technical University Berlin, 10587 Berlin, Germany
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8
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Yue S, Panagiotopoulos AZ. Dynamic properties of aqueous electrolyte solutions from non-polarisable, polarisable, and scaled-charge models. Mol Phys 2019. [DOI: 10.1080/00268976.2019.1645901] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
- Shuwen Yue
- Department of Chemical and Biological Engineering, Princeton University, Princeton, NJ, USA
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9
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Choudhary A, Chandra A. An ab initio molecular dynamics study of benzene in water at supercritical conditions: Structure, dynamics, and polarity of hydration shell water and the solute. J Chem Phys 2019; 151:044508. [PMID: 31370512 DOI: 10.1063/1.5094570] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Anisotropic structure and dynamics of the hydration shell of a benzene solute in supercritical water are investigated by means of ab initio molecular dynamics simulations. The polarity and structural distortion of the benzene solute in supercritical water are also investigated in this study. Calculations are done at 673 K for three different densities of the solvent. The simulations are carried out using the Becke-Lee-Yang-Parr (BLYP) and also the Becke-Lee-Yang-Parr functional including dispersion corrections of Grimme (BYLP-D). The structural anisotropy is found to exist even at supercritical conditions as elucidated by the radial distribution functions of different conical regions and also by angular and spatial distribution functions. The benzene-water πH-bond and also the water-water hydrogen bonds are found to exist even at the supercritical temperature of 673 K. However, the numbers of these hydrogen bonds are reduced substantially with a decrease in water density. The water molecules in the axial region of benzene are found to be preferably oriented with one OH vector pointing toward the benzene ring, whereas the water molecules located in the equatorial region are found to orient their dipoles mostly parallel to the ring plane. The orientational distributions, however, are found to be rather broad at the supercritical temperature due to thermal fluctuations. Although the water molecules have faster dynamics at these supercritical conditions, a slight difference is observed in the dynamics of the solvation shell and bulk molecules. The conformational flexibility of the ring is found to be enhanced which causes an increase in polarity of the benzene solute in water under supercritical conditions.
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Affiliation(s)
- Ashu Choudhary
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, India
| | - Amalendu Chandra
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, India
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10
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Kameda Y, Amo Y, Usuki T, Umebayashi Y, Ikeda K, Otomo T. Origin of the Difference in Ion-Water Distances Determined by X-ray and Neutron Diffraction Measurements for Aqueous NaCl and KCl Solutions. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2019. [DOI: 10.1246/bcsj.20180283] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Affiliation(s)
- Yasuo Kameda
- Department of Material and Biological Chemistry, Faculty of Science, Yamagata University, Yamagata 990-8560, Japan
| | - Yuko Amo
- Department of Material and Biological Chemistry, Faculty of Science, Yamagata University, Yamagata 990-8560, Japan
| | - Takeshi Usuki
- Department of Material and Biological Chemistry, Faculty of Science, Yamagata University, Yamagata 990-8560, Japan
| | - Yasuhiro Umebayashi
- Graduate School of Science and Technology, Niigata University, Niigata 950-2181, Japan
| | - Kazutaka Ikeda
- Institute of Material Structure Science, KEK, Tsukuba, Ibaraki 305-080, Japan
| | - Toshiya Otomo
- Institute of Material Structure Science, KEK, Tsukuba, Ibaraki 305-080, Japan
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11
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Peng H, Nguyen AV. A link between viscosity and cation-anion contact pairs: Adventure on the concept of structure-making/breaking for concentrated salt solutions. J Mol Liq 2018. [DOI: 10.1016/j.molliq.2018.04.145] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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12
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Sindt JO, Alexander AJ, Camp PJ. Effects of nanoparticle heating on the structure of a concentrated aqueous salt solution. J Chem Phys 2018; 147:214506. [PMID: 29221397 DOI: 10.1063/1.5002002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The effects of a rapidly heated nanoparticle on the structure of a concentrated aqueous salt solution are studied using molecular dynamics simulations. A diamond-like nanoparticle of radius 20 Å is immersed in a sodium-chloride solution at 20% above the experimental saturation concentration and equilibrated at T = 293 K and P = 1 atm. The nanoparticle is then rapidly heated to several thousand degrees Kelvin, and the system is held under isobaric-isoenthalpic conditions. It is observed that after 2-3 ns, the salt ions are depleted far more than water molecules from a proximal zone 15-25 Å from the nanoparticle surface. This leads to a transient reduction in molality in the proximal zone and an increase in ion clustering in the distal zone. At longer times, ions begin to diffuse back into the proximal zone. It is speculated that the formation of proximal and distal zones, and the increase in ion clustering, plays a role in the mechanism of nonphotochemical laser-induced nucleation.
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Affiliation(s)
- Julien O Sindt
- School of Engineering, University of Edinburgh, Mayfield Road, Edinburgh EH9 3JL, Scotland
| | - Andrew J Alexander
- School of Chemistry, University of Edinburgh, David Brewster Road, Edinburgh EH9 3FJ, Scotland
| | - Philip J Camp
- School of Chemistry, University of Edinburgh, David Brewster Road, Edinburgh EH9 3FJ, Scotland
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13
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Peng H, Firouzi M. Evaluation of interfacial properties of concentrated KCl solutions by molecular dynamics simulation. Colloids Surf A Physicochem Eng Asp 2018. [DOI: 10.1016/j.colsurfa.2017.11.063] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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14
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Modarresi M, Franco-Gonzalez JF, Zozoulenko I. Morphology and ion diffusion in PEDOT:Tos. A coarse grained molecular dynamics simulation. Phys Chem Chem Phys 2018; 20:17188-17198. [DOI: 10.1039/c8cp02902d] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A Martini coarse-grained Molecular Dynamics (MD) model for the doped conducting polymer poly(3,4-ethylenedioxythiophene) (PEDOT) is developed. It is shown that the diffusion coefficients decrease exponentially as the hydration level is reduced.
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Affiliation(s)
- Mohsen Modarresi
- Laboratory of Organic Electronics
- Department of Science and Technology
- Linköping University
- 60174 Norrköping
- Sweden
| | - Juan Felipe Franco-Gonzalez
- Laboratory of Organic Electronics
- Department of Science and Technology
- Linköping University
- 60174 Norrköping
- Sweden
| | - Igor Zozoulenko
- Laboratory of Organic Electronics
- Department of Science and Technology
- Linköping University
- 60174 Norrköping
- Sweden
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15
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Li K, Liu L, Wu H, Li S, Yu C, Zhou Y, Huang W, Yan D. Understanding the temperature effect on transport dynamics and structures in polyamide reverse osmosis system via molecular dynamics simulations. Phys Chem Chem Phys 2018; 20:29996-30005. [DOI: 10.1039/c8cp05825c] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Molecular simulations could disclose the transport dynamics, membrane structures and temperature effect on reverse osmosis process.
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Affiliation(s)
- Ke Li
- School of Chemistry & Chemical Engineering, State Key Laboratory of Metal Matrix Composites, Shanghai Key Laboratory of Electrical Insulation and Thermal Aging, Shanghai Jiao Tong University
- Shanghai
- China
| | - Lifen Liu
- Center for Membrane and Water Science & Technology, Ocean College, Zhejiang University of Technology
- Hangzhou
- China
| | - Hao Wu
- Center for Membrane and Water Science & Technology, Ocean College, Zhejiang University of Technology
- Hangzhou
- China
| | - Shanlong Li
- School of Chemistry & Chemical Engineering, State Key Laboratory of Metal Matrix Composites, Shanghai Key Laboratory of Electrical Insulation and Thermal Aging, Shanghai Jiao Tong University
- Shanghai
- China
| | - Chunyang Yu
- School of Chemistry & Chemical Engineering, State Key Laboratory of Metal Matrix Composites, Shanghai Key Laboratory of Electrical Insulation and Thermal Aging, Shanghai Jiao Tong University
- Shanghai
- China
| | - Yongfeng Zhou
- School of Chemistry & Chemical Engineering, State Key Laboratory of Metal Matrix Composites, Shanghai Key Laboratory of Electrical Insulation and Thermal Aging, Shanghai Jiao Tong University
- Shanghai
- China
| | - Wei Huang
- School of Chemistry & Chemical Engineering, State Key Laboratory of Metal Matrix Composites, Shanghai Key Laboratory of Electrical Insulation and Thermal Aging, Shanghai Jiao Tong University
- Shanghai
- China
| | - Deyue Yan
- School of Chemistry & Chemical Engineering, State Key Laboratory of Metal Matrix Composites, Shanghai Key Laboratory of Electrical Insulation and Thermal Aging, Shanghai Jiao Tong University
- Shanghai
- China
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16
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Bhadauria R, Aluru NR. Multiscale modeling of electroosmotic flow: Effects of discrete ion, enhanced viscosity, and surface friction. J Chem Phys 2017. [DOI: 10.1063/1.4982731] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Affiliation(s)
- Ravi Bhadauria
- Department of Mechanical Science and Engineering, Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
| | - N. R. Aluru
- Department of Mechanical Science and Engineering, Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
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17
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Benavides A, Portillo M, Abascal J, Vega C. Estimating the solubility of 1:1 electrolyte aqueous solutions: the chemical potential difference rule. Mol Phys 2017. [DOI: 10.1080/00268976.2017.1288939] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Affiliation(s)
- A.L. Benavides
- División de Ciencias e Ingenierías, Universidad de Guanajuato, Guanajuato, Mexico
| | - M.A. Portillo
- Departamento de Química Física, Facultad de Ciencias Químicas, Universidad Complutense de Madrid, 28040 Madrid, Spain
| | - J.L.F. Abascal
- Departamento de Química Física, Facultad de Ciencias Químicas, Universidad Complutense de Madrid, 28040 Madrid, Spain
| | - C. Vega
- Departamento de Química Física, Facultad de Ciencias Químicas, Universidad Complutense de Madrid, 28040 Madrid, Spain
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18
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Bitterfield DL, Utoft A, Needham D. An Activity-Based Dissolution Model for Solute-Containing Microdroplets. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2016; 32:12749-12759. [PMID: 27802055 DOI: 10.1021/acs.langmuir.6b03126] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
When a solute is present in an aqueous droplet, the water activity in the droplet and the rate of droplet dissolution are both decreased (as compared to a pure water droplet). One of the main parameters that controls this effect is the dynamically changing solute concentration, and therefore water activity and chemical potential, at the droplet interface. This work addresses the importance of understanding how water activity changes during solution droplet dissolution. A model for dissolution rate is presented that accounts for the kinetic effects of changing water activity at the droplet interface during the dissolution of an aqueous salt solution microdroplet into a second immiscible liquid phase. The important underlying question in this model is whether the dissolving component can be considered in local equilibrium on both sides of the droplet interface and whether this assumption is sufficient to account for the kinetics of dissolution. The dissolution model is based on the Epstein-Plesset equation, which has previously been applied to pure gas (bubble) and liquid (droplet) dissolution into liquid phases, but not to salt solutions. The model is tested by using the micropipet technique to form and observe the dehydration of single NaCl solution microdroplets in octanol or butyl acetate. The model successfully predicts the droplet diameter as a function of time in both organic solvents. The NaCl concentration in water is measured well into the supersaturated area >5.4 M, and the supersaturation limit at which NaCl nucleation happens is reported to be 10.24 ± 0.31 M.
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Affiliation(s)
- Deborah L Bitterfield
- Department of Mechanical Engineering and Materials Science, Duke University , Durham, North Carolina 27708, United States
| | - Anders Utoft
- Center for Single Particle Science and Engineering (SPSE), University of Southern Denmark , Odense, Denmark
| | - David Needham
- Department of Mechanical Engineering and Materials Science, Duke University , Durham, North Carolina 27708, United States
- Center for Single Particle Science and Engineering (SPSE), University of Southern Denmark , Odense, Denmark
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19
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Benavides AL, Aragones JL, Vega C. Consensus on the solubility of NaCl in water from computer simulations using the chemical potential route. J Chem Phys 2016; 144:124504. [PMID: 27036458 DOI: 10.1063/1.4943780] [Citation(s) in RCA: 83] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The solubility of NaCl in water is evaluated by using three force field models: Joung-Cheatham for NaCl dissolved in two different water models (SPC/E and TIP4P/2005) and Smith Dang NaCl model in SPC/E water. The methodology based on free-energy calculations [E. Sanz and C. Vega, J. Chem. Phys. 126, 014507 (2007)] and [J. L. Aragones et al., J. Chem. Phys. 136, 244508 (2012)] has been used, except, that all calculations for the NaCl in solution were obtained by using molecular dynamics simulations with the GROMACS package instead of homemade MC programs. We have explored new lower molalities and made longer runs to improve the accuracy of the calculations. Exploring the low molality region allowed us to obtain an analytical expression for the chemical potential of the ions in solution as a function of molality valid for a wider range of molalities, including the infinite dilute case. These new results are in better agreement with recent estimations of the solubility obtained with other methodologies. Besides, two empirical simple rules have been obtained to have a rough estimate of the solubility of a certain model, by analyzing the ionic pairs formation as a function of molality and/or by calculating the difference between the NaCl solid chemical potential and the standard chemical potential of the salt in solution.
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Affiliation(s)
- A L Benavides
- Departamento de Química Física, Facultad de Ciencias Químicas, Universidad Complutense de Madrid, 28040 Madrid, Spain
| | - J L Aragones
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - C Vega
- Departamento de Química Física, Facultad de Ciencias Químicas, Universidad Complutense de Madrid, 28040 Madrid, Spain
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SARKAR ATANU, CHATTERJEE ANUPAM, TIWARI SC, TEMBE BL. Na+ Cl− ion pair association in water-DMSO mixtures: Effect of ion pair model potentials. J CHEM SCI 2016. [DOI: 10.1007/s12039-016-1093-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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21
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van der Vegt NFA, Haldrup K, Roke S, Zheng J, Lund M, Bakker HJ. Water-Mediated Ion Pairing: Occurrence and Relevance. Chem Rev 2016; 116:7626-41. [DOI: 10.1021/acs.chemrev.5b00742] [Citation(s) in RCA: 155] [Impact Index Per Article: 19.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Nico F. A. van der Vegt
- Eduard-Zintl-Institut
für Anorganische und Physikalische Chemie and Center of Smart
Interfaces, Technische Universität Darmstadt, Alarich-Weiss-Strasse
10, 64287 Darmstadt, Germany
| | - Kristoffer Haldrup
- Physics
Department, NEXMAP Section, Technical University of Denmark, Fysikvej
307, 2800 Kongens
Lyngby, Denmark
| | - Sylvie Roke
- Laboratory
for Fundamental BioPhotonics, Institute of Bioengineering, and Institute
of Materials Science, School of Engineering, and Lausanne Centre for
Ultrafast Science, École Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland
| | - Junrong Zheng
- College
of Chemistry and Molecular Engineering, Beijing National Laboratory
for Molecular Sciences, Peking University, Beijing 100871, China
- Department
of Chemistry, Rice University, 6100 Main Street, Houston, Texas 77005-1892, United States
| | - Mikael Lund
- Division
of Theoretical Chemistry, Department of Chemistry, Lund University, SE-22100 Lund, Sweden
| | - Huib J. Bakker
- FOM Institute AMOLF, Science
Park 104, 1098 XG Amsterdam, The Netherlands
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22
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Calixte EI, Samoylova ON, Shuford KL. Confinement and surface effects of aqueous solutions within charged carbon nanotubes. Phys Chem Chem Phys 2016; 18:12204-12. [DOI: 10.1039/c5cp04446d] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Size-charge effects of brines in charged nanotubes from a molecular dynamics investigation of ion hydration, water coordination, and hydrogen bonding.
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Affiliation(s)
- Emvia I. Calixte
- Department of Chemistry and Biochemistry
- Baylor University
- Waco
- USA
| | | | - Kevin L. Shuford
- Department of Chemistry and Biochemistry
- Baylor University
- Waco
- USA
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23
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Auffinger P, Cheatham TE, Vaiana AC. Spontaneous Formation of KCl Aggregates in Biomolecular Simulations: A Force Field Issue? J Chem Theory Comput 2015; 3:1851-9. [PMID: 26627627 DOI: 10.1021/ct700143s] [Citation(s) in RCA: 152] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Realistic all-atom simulation of biological systems requires accurate modeling of both the biomolecules and their ionic environment. Recently, ion nucleation phenomena leading to the rapid growth of KCl or NaCl clusters in the vicinity of biomolecular systems have been reported. To better understand this phenomenon, molecular dynamics simulations of KCl aqueous solutions at three (1.0, 0.25, and 0.10 M) concentrations were performed. Two popular water models (TIP3P and SPC/E) and two Lennard-Jones parameter sets (AMBER and Dang) were combined to produce a total of 80 ns of molecular dynamics trajectories. Results suggest that the use of the Dang cation Lennard-Jones parameters instead of those adopted by the AMBER force-field produces a more accurate description of the ionic solution. In the later case, formation of salt aggregates is probably indicative of an artifact resulting from misbalanced force-field parameters. Because similar results were obtained with two different water parameter sets, the simulations exclude a water model dependency in the formation of anomalous ionic clusters. Overall, the results strongly suggest that for accurate modeling of ions in biomolecular systems, great care should be taken in choosing balanced ionic parameters even when using the most popular force-fields. These results invite a reexamination of older data obtained using available force-fields and a thorough check of the quality of current parameters sets by performing simulations at finite (>0.25 M) instead of minimal salt conditions.
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Affiliation(s)
- Pascal Auffinger
- Architecture et Réactivité de l'ARN, Université Louis Pasteur de Strasbourg, CNRS, IBMC, 15 rue René Descartes, 67084 Strasbourg, France, and Department of Medical Chemistry, Pharmaceutical Chemistry and Pharmaceutics and Bioengineering, University of Utah, Salt Lake City, Utah 84112
| | - Thomas E Cheatham
- Architecture et Réactivité de l'ARN, Université Louis Pasteur de Strasbourg, CNRS, IBMC, 15 rue René Descartes, 67084 Strasbourg, France, and Department of Medical Chemistry, Pharmaceutical Chemistry and Pharmaceutics and Bioengineering, University of Utah, Salt Lake City, Utah 84112
| | - Andrea C Vaiana
- Architecture et Réactivité de l'ARN, Université Louis Pasteur de Strasbourg, CNRS, IBMC, 15 rue René Descartes, 67084 Strasbourg, France, and Department of Medical Chemistry, Pharmaceutical Chemistry and Pharmaceutics and Bioengineering, University of Utah, Salt Lake City, Utah 84112
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24
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Sarkar A, Tembe B. Molecular dynamics simulations of alkali metal halides in supercritical water. Chem Phys Lett 2015. [DOI: 10.1016/j.cplett.2015.08.032] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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25
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Chen H, Ruckenstein E. Hydrated Ions: From Individual Ions to Ion Pairs to Ion Clusters. J Phys Chem B 2015; 119:12671-6. [DOI: 10.1021/acs.jpcb.5b06837] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Houyang Chen
- Department of Chemical and
Biological Engineering, State University of New York at Buffalo, Buffalo, New York 14260-4200, United States
| | - Eli Ruckenstein
- Department of Chemical and
Biological Engineering, State University of New York at Buffalo, Buffalo, New York 14260-4200, United States
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26
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Choudhary A, Chandra A. Spatial and Orientational Structure of the Hydration Shell of Benzene in Sub- and Supercritical Water. J Phys Chem B 2015; 119:8600-12. [DOI: 10.1021/acs.jpcb.5b03371] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Ashu Choudhary
- Department
of Chemistry, Indian Institute of Technology Kanpur, Kanpur, India 208016
| | - Amalendu Chandra
- Department
of Chemistry, Indian Institute of Technology Kanpur, Kanpur, India 208016
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27
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Shen H, Hao T, Wen J, Tan RR, Zhang FS. Properties of pure water and sodium chloride solutions at high temperatures and pressures: a simulation study. MOLECULAR SIMULATION 2015. [DOI: 10.1080/08927022.2014.992019] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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28
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29
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Bouazizi S, Nasr S. Concentration effects on aqueous lithium chloride solutions. Molecular dynamics simulations and x-ray scattering studies. J Mol Liq 2014. [DOI: 10.1016/j.molliq.2014.04.018] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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30
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Reiser S, Deublein S, Vrabec J, Hasse H. Molecular dispersion energy parameters for alkali and halide ions in aqueous solution. J Chem Phys 2014; 140:044504. [DOI: 10.1063/1.4858392] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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31
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Wiedemair MJ, Weiss AKH, Rode BM. Ab initio quantum mechanical simulations confirm the formation of all postulated species in ionic dissociation. Phys Chem Chem Phys 2014; 16:7368-76. [DOI: 10.1039/c3cp54986k] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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32
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33
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Yang XQ, Li K, Chen X, Huang KM, Liu PK. Molecular dynamics simulations and experimental measurements of complex permittivity of aqueous solutions of NaCl at remote sensing frequencies. RUSSIAN JOURNAL OF PHYSICAL CHEMISTRY A 2013. [DOI: 10.1134/s0036024413100245] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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34
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Shevkunov SV. Computer simulation of dissociative equilibrium in aqueous NaCl electrolyte with account for polarization and ion recharging. Model of interactions. RUSS J ELECTROCHEM+ 2013. [DOI: 10.1134/s1023193513030129] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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35
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Shevkunov SV. Computer simulation of dissociative equilibrium in aqueous NaCl electrolyte with account for polarization and ion recharging. Ionization mechanism. RUSS J ELECTROCHEM+ 2013. [DOI: 10.1134/s1023193513030130] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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36
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Zhang Q, Xie W, Bian H, Gao YQ, Zheng J, Zhuang W. Microscopic Origin of the Deviation from Stokes–Einstein Behavior Observed in Dynamics of the KSCN Aqueous Solutions: A MD Simulation Study. J Phys Chem B 2013; 117:2992-3004. [DOI: 10.1021/jp400441e] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- Qiang Zhang
- State Key Laboratory of Molecular
Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, Liaoning,
People’s Republic of China
- Department of Chemistry, Bohai University, Jinzhou 121000, China
| | - Wenjun Xie
- College of Chemistry and Molecular
Engineering, Beijing National Laboratory for Molecular Sciences, Peking University, Beijing 100871, China
| | - HongTao Bian
- Department of Chemistry, Rice University, Houston, Texas 77005, United States
| | - Yi Qin Gao
- College of Chemistry and Molecular
Engineering, Beijing National Laboratory for Molecular Sciences, Peking University, Beijing 100871, China
| | - Junrong Zheng
- Department of Chemistry, Rice University, Houston, Texas 77005, United States
| | - Wei Zhuang
- State Key Laboratory of Molecular
Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, Liaoning,
People’s Republic of China
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37
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Dixit MK, Tembe B. Potentials of mean force of sodium chloride ion pair in dimethyl sulfoxide–methanol mixtures. J Mol Liq 2013. [DOI: 10.1016/j.molliq.2012.09.026] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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38
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Influence of Magnetic Field on Aqueous NaCl Solutions: A Foundational Research on the Desalination Method Based on the Rotating Electromagnetic Effect. ACTA ACUST UNITED AC 2012. [DOI: 10.4028/www.scientific.net/amr.591-593.2607] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In order to investigate whether magnetic field can improve the seawater desalination efficiency, the influence of magnetic field on the aqueous solutions of NaCl is studied by molecular dynamics (MD) simulations. The results show that, under the influence of magnetic field, the hydration number of Cl- ions increases and the mobility of hydrated Cl- ions is weakened, while the mean size of water clusters decreases and the mobility of water molecules is enhanced. These may lead to higher salt rejection and water flux by the usage of magnetic field in our novel desalination method based on rotating electromagnetic effect.
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39
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Zhu H, Ghoufi A, Szymczyk A, Balannec B, Morineau D. Computation of the hindrance factor for the diffusion for nanoconfined ions: molecular dynamics simulations versus continuum-based models. Mol Phys 2012. [DOI: 10.1080/00268976.2011.645896] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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40
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Hajari T, Ganguly P, van der Vegt NFA. Enthalpy–Entropy of Cation Association with the Acetate Anion in Water. J Chem Theory Comput 2012; 8:3804-9. [DOI: 10.1021/ct300074d] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Timir Hajari
- Center of Smart Interfaces, Technische Universität Darmstadt, 64287 Darmstadt, Germany
| | - Pritam Ganguly
- Center of Smart Interfaces, Technische Universität Darmstadt, 64287 Darmstadt, Germany
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41
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GUPTA RINI, CHANDRA AMALENDU. SINGLE-PARTICLE AND PAIR DYNAMICAL PROPERTIES OF ACETONE–METHANOL MIXTURES CONTAINING CHARGED AND NEUTRAL SOLUTES: A MOLECULAR DYNAMICS STUDY. JOURNAL OF THEORETICAL & COMPUTATIONAL CHEMISTRY 2012. [DOI: 10.1142/s0219633611006438] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The dynamical properties of acetone–methanol mixtures containing either an ionic or a neutral hydrophobic solute are investigated by means of a series of molecular dynamics simulations. The primary goal has been to study how the solute and solvent dynamical properties change with variation of composition of the mixture ranging from pure acetone to pure methanol. The variations of structure and energetics of the mixture with composition are also calculated. The diffusion coefficients of both ionic and neutral solutes are found to show nonlinear variation with composition of the mixture, although the extent of nonlinearity in the diffusion of the neutral solute is much weaker. Calculations of appropriate solute-solvent distribution functions reveal the extent and nature of selective solvation of these solute species which play a role in determining the nonideal dynamical characteristics of these solutes. The free energies of solvation of the ionic solutes are also calculated and the results are discussed in the context of their dynamical behavior. The hydrogen bond statistics and dynamics of these mixtures are also calculated over their entire composition range. The energies and lifetimes of hydrogen bonds between an acetone and a methanol molecule or between two methanol molecules are found to increase with increase of acetone mole fraction of the mixture. Residence times of methanol molecules in solvation shells of acetone and methanol are also found to follow the same trend as relaxation times. However, these pair dynamical properties show essentially linear dependence on composition, thus behave almost ideally with respect to changes in composition of the mixture.
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Affiliation(s)
- RINI GUPTA
- Department of Chemistry, Indian Institute of Technology, Kanpur, India 208016, India
| | - AMALENDU CHANDRA
- Department of Chemistry, Indian Institute of Technology, Kanpur, India 208016, India
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42
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Ho TA, Argyris D, Cole DR, Striolo A. Aqueous NaCl and CsCl solutions confined in crystalline slit-shaped silica nanopores of varying degree of protonation. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2012; 28:1256-1266. [PMID: 22148873 DOI: 10.1021/la2036086] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
All-atom molecular dynamics simulations were conducted to study the dynamics of aqueous electrolyte solutions confined in slit-shaped silica nanopores of various degrees of protonation. Five degrees of protonation were prepared by randomly removing surface hydrogen atoms from fully protonated crystalline silica surfaces. Aqueous electrolyte solutions containing NaCl or CsCl salt were simulated at ambient conditions. In all cases, the ionic concentration was 1 M. The results were quantified in terms of atomic density distributions within the pores, and the self-diffusion coefficient along the direction parallel to the pore surface. We found evidence for ion-specific properties that depend on ion-surface, water-ion, and only in some cases ion-ion correlations. The degree of protonation strongly affects the structure, distribution, and the dynamic behavior of confined water and electrolytes. Cl(-) ions adsorb on the surface at large degrees of protonation, and their behavior does not depend significantly on the cation type (either Na(+) or Cs(+) ions are present in the systems considered). The cations show significant ion-specific behavior. Na(+) ions occupy different positions within the pore as the degree of protonation changes, while Cs(+) ions mainly remain near the pore center at all conditions considered. For a given degree of protonation, the planar self-diffusion coefficient of Cs(+) is always greater than that of Na(+) ions. The results are useful for better understanding transport under confinement, including brine behavior in the subsurface, with important applications such as environmental remediation.
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Affiliation(s)
- Tuan A Ho
- School of Chemical, Biological and Materials Engineering, University of Oklahoma, Norman, Oklahoma 73019, USA
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43
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Beladjine S, Amrani M, Zanoun A, Belaidi A, Vergoten G. Structure and hydrogen bonding in aqueous sodium chloride solutions using theoretical water model AB4: Effects of concentration. COMPUT THEOR CHEM 2011. [DOI: 10.1016/j.comptc.2011.09.010] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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44
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Temperature and density effects on structural features of a dilute aqueous lithium chloride solution at near- and supercritical conditions. J Mol Liq 2011. [DOI: 10.1016/j.molliq.2011.04.014] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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45
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Gupta R, Chandra A. Nonideality in diffusion of ionic and neutral solutes and hydrogen bond dynamics in dimethyl sulfoxide-chloroform mixtures of varying composition. J Comput Chem 2011; 32:2679-89. [DOI: 10.1002/jcc.21849] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2010] [Revised: 04/14/2011] [Accepted: 05/10/2011] [Indexed: 12/11/2022]
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46
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Gupta R, Chandra A. Structural, single-particle and pair dynamical properties of acetone–chloroform mixtures with dissolved solutes. Chem Phys 2011. [DOI: 10.1016/j.chemphys.2011.03.029] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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47
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Reif MM, Hünenberger PH. Computation of methodology-independent single-ion solvation properties from molecular simulations. IV. Optimized Lennard-Jones interaction parameter sets for the alkali and halide ions in water. J Chem Phys 2011; 134:144104. [DOI: 10.1063/1.3567022] [Citation(s) in RCA: 118] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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48
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Understanding the role of ion interactions in soluble salt flotation with alkylammonium and alkylsulfate collectors. Adv Colloid Interface Sci 2011; 163:1-22. [PMID: 21353193 DOI: 10.1016/j.cis.2011.01.003] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2010] [Revised: 01/06/2011] [Accepted: 01/10/2011] [Indexed: 11/22/2022]
Abstract
There is anecdotal evidence for the significant effects of salt ions on the flotation separation of minerals using process water of high salt content. Examples include flotation of soluble salt minerals such as potash, trona and borax in brine solutions using alkylammonium and alkylsulfate collectors such as dodecylamine hydrochloride and sodium dodecylsulfate. Although some of the effects are expected, some do not seem to be encompassed by classical theories of colloid science. Several experimental and modeling techniques for determining solution viscosity, surface tension, bubble-particle attachment time, contact angle, and molecular dynamics simulation have been used to provide further information on air-solution and solid-solution interfacial phenomena, especially with respect to the interfacial water structure due to the presence of dissolved ions. In addition atomic force microscopy, and sum frequency generation vibrational spectroscopy have been used to provide further information on surface states. These studies indicate that the ion specificity effect is the most significant factor influencing flotation in brine solutions.
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50
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Zwier MC, Kaus JW, Chong LT. Efficient Explicit-Solvent Molecular Dynamics Simulations of Molecular Association Kinetics: Methane/Methane, Na+/Cl−, Methane/Benzene, and K+/18-Crown-6 Ether. J Chem Theory Comput 2011; 7:1189-97. [DOI: 10.1021/ct100626x] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Matthew C. Zwier
- Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
| | - Joseph W. Kaus
- Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
| | - Lillian T. Chong
- Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
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