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Pal M, Bandyopadhyay D, Choudhury N. Surface morphology and dispersion interaction induced anomalous dynamics of solvation water of a hydrophobic fullerene molecule. J Mol Liq 2022. [DOI: 10.1016/j.molliq.2022.118495] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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2
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Zhang R, Troya D, Madsen LA. Prolonged Association between Water Molecules under Hydrophobic Nanoconfinement. J Phys Chem B 2021; 125:13767-13777. [PMID: 34898212 DOI: 10.1021/acs.jpcb.1c06810] [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
We present an investigation of the dynamics of water confined among rigid carbon rods and between parallel graphene sheets with molecular dynamics simulations. Diffusion coefficients, activation energy of diffusion, and residence-time correlation functions as a function of confinement geometry reveal a retardation of water dynamics under hydrophobic confinement compared to bulk water. In fact, water under various confinements possesses longer associations with its neighbors and exhibits diffusion dynamics characteristic of a lower temperature. Analysis of the residence-time correlation functions reveals long and short residence times, which we relate to the diffusion coefficient and activation energy of diffusion, respectively. Additional investigations reveal how the level of confining surface hydrophobicity affects water dynamics, further broadening our understanding of water diffusion inside diverse media. Overall, this study sheds light on the physical origin of retarded water dynamics under hydrophobic confinement and the close relationship between residence times and diffusion behavior.
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Affiliation(s)
- Rui Zhang
- Department of Chemistry and Macromolecules Innovation Institute, Virginia Tech, Blacksburg, Virginia 24061, United States
| | - Diego Troya
- Department of Chemistry and Macromolecules Innovation Institute, Virginia Tech, Blacksburg, Virginia 24061, United States
| | - Louis A Madsen
- Department of Chemistry and Macromolecules Innovation Institute, Virginia Tech, Blacksburg, Virginia 24061, United States
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Tendong E, Dasgupta TS, Chakrabarti J. Dynamics of water trapped in transition metal oxide-graphene nano-confinement. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2020; 32:325101. [PMID: 32191936 DOI: 10.1088/1361-648x/ab814f] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Accepted: 03/19/2020] [Indexed: 06/10/2023]
Abstract
Motivated by practical implementation of transition-metal oxide-graphene heterostructures, we use all atom molecular dynamics simulations to study dynamics of water in a nano slit bounded by a transition metal oxide surface, namely, TiO2termination of SrTiO3, and graphene. The resultant asymmetric, strong confinement produces square ice-like crystallites of water pinned at TiO2surface and drives enhanced hydrophobicity of graphene via the proximity effect to the hydrophilic TiO2surface. This importantly brings in dynamic heterogeneity, both in translational and rotational degrees of freedom, due to coupling between the slow relaxing, strongly adsorbed water layer at the hydrophilic oxide surface, and faster relaxation of subsequent water layers. The heterogeneity is signalled in the ruggedness of the effective free energy landscapes. We discuss possible implications of our findings in drug delivery.
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Affiliation(s)
- E Tendong
- Department of Condensed Matter Physics and Material Sciences & Department of Chemical Biological and Macromoleculer Sciences, S N Bose National Centre for Basic Sciences, Block JD, Sector III, Salt Lake, Kolkata - 700106, India
| | - T Saha Dasgupta
- Department of Condensed Matter Physics and Material Sciences & Department of Chemical Biological and Macromoleculer Sciences, S N Bose National Centre for Basic Sciences, Block JD, Sector III, Salt Lake, Kolkata - 700106, India
| | - J Chakrabarti
- Department of Condensed Matter Physics and Material Sciences,Thematic Unit of Excellence for Material Science & Technology Research Centre, S N Bose National Centre for Basic Sciences, Block JD, Sector III, Salt Lake, Kolkata - 700106, India
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4
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Varghese S, Kannam SK, Hansen JS, P Sathian S. Effect of Hydrogen Bonds on the Dielectric Properties of Interfacial Water. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:8159-8166. [PMID: 31121091 DOI: 10.1021/acs.langmuir.9b00543] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The dielectric constant for water is reduced under confinement. Although this phenomenon is well known, the underlying physical mechanism for the reduction is still in debate. In this work, we investigate the effect of the orientation of hydrogen bonds on the dielectric properties of confined water using molecular dynamics simulations. We find a reduced rotational diffusion coefficient for water molecules close to the solid surface. The reduced rotational diffusion arises due to the hindered rotation away from the plane parallel to the channel walls. The suppressed rotation in turn affects the orientational polarization of water, leading to a low value for the dielectric constant at the interface. We attribute the constrained out-of-plane rotation to originate from a higher density of planar hydrogen bonds formed by the interfacial water molecules.
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Affiliation(s)
- Sleeba Varghese
- Department of Applied Mechanics , Indian Institute of Technology Madras , Chennai 600036 , India
| | - Sridhar Kumar Kannam
- Faculty of Science, Engineering and Technology , Swinburne University of Technology , Melbourne , Victoria 3122 , Australia
- School of Applied Sciences , RMIT University , Melbourne , Victoria 3001 , Australia
| | - Jesper Schmidt Hansen
- Department of Science and Environment , Roskilde University , Roskilde 4000 , Denmark
| | - Sarith P Sathian
- Department of Applied Mechanics , Indian Institute of Technology Madras , Chennai 600036 , India
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5
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Kumar H, Dasgupta C, Maiti PK. Phase Transition in Monolayer Water Confined in Janus Nanopore. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2018; 34:12199-12205. [PMID: 30216072 DOI: 10.1021/acs.langmuir.8b02147] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The ubiquitous nature of water invariably leads to a variety of physical scenarios that can result in many intriguing properties. We investigate the thermodynamics and associated phase transitions for a water monolayer confined within a quasi-two-dimensional nanopore. An asymmetric nanopore constructed by combining a hydrophilic (hexagonal boron nitride) sheet and a hydrophobic (graphene) sheet leads to an ordered water structure at much higher temperatures compared to a symmetric hydrophobic nanopore consisting of two graphene sheets. The discontinuous change in the thermodynamic quantities, potential energy ( U), and entropy ( S) of confined water molecules computed from the all-atom molecular dynamics simulation trajectories, uncovers a first-order phase transition in the temperature range of T = 320-330 K. Structural analysis reveals that water molecules undergo a disorder-to-order phase transformation in this temperature range with a 4-fold symmetric phase persisting at lower temperatures. Our findings predict a novel confinement system which has the melting transition for monolayer water above the room temperature, and provide a microscopic understanding which will have important implications for other nanofludic systems as well.
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Affiliation(s)
- Hemant Kumar
- Department of Material Sciences and Engineering , University of Pennsylvania , Philadelphia , Pennsylvania 19104 , United States
| | - Chandan Dasgupta
- Centre for Condensed Matter Theory, Department of Physics , Indian Institute of Science , Bangalore 560012 , India
- International Centre for Theoretical Sciences , Bangalore 560089 , India
| | - Prabal K Maiti
- Centre for Condensed Matter Theory, Department of Physics , Indian Institute of Science , Bangalore 560012 , India
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6
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Molecular dynamics simulation study of hydration of uranyl nitrate in supercritical water: Dissecting the effect of uranyl ion concentration from solvent density. Chem Phys 2017. [DOI: 10.1016/j.chemphys.2017.09.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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7
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Chopra M, Choudhury N. Structural and dynamical aspects of uranyl ions in supercritical water: A molecular dynamics simulation study. J Mol Liq 2016. [DOI: 10.1016/j.molliq.2016.09.118] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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8
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Mozaffari F. A molecular dynamics simulation study of the effect of water–graphene interaction on the properties of confined water. MOLECULAR SIMULATION 2016. [DOI: 10.1080/08927022.2016.1204659] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Huang Y, Zhou G, Li Y, Yang Z, Shi M, Wang X, Chen X, Zhang F, Li W. Molecular dynamics simulations of temperature-dependent structures and dynamics of ethylammonium nitrate protic ionic liquid: The role of hydrogen bond. Chem Phys 2016. [DOI: 10.1016/j.chemphys.2016.03.020] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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10
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Chopra M, Choudhury N. Molecular dynamics simulation study of distribution and dynamics of aqueous solutions of uranyl ions: the effect of varying temperature and concentration. Phys Chem Chem Phys 2015; 17:27840-50. [PMID: 26439497 DOI: 10.1039/c5cp03769g] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Investigating the characteristics of actinyl ions has been of great interest due to their direct relevance in the nuclear fuel cycle. All-atom molecular dynamics simulations have been employed to study the orientational structure and dynamics of aqueous solutions of uranyl ions of various concentrations. The orientational structure of water around a uranyl ion has been thoroughly investigated by calculating different orientational probability distributions corresponding to different molecular axes of water. The orientational distribution of water molecules in the first coordination shell of a uranyl ion is found to be markedly different from that in bulk water. Analysis of counterion distribution around the uranyl ion reveals the presence of nitrate ions along with water molecules in the first solvation shell. From the comparison of the number of coordinated water and nitrate ions at various uranyl nitrate concentrations, it is evident that these two species compete for occupying the first solvation shell of the uranyl ion. Orientational dynamics of water molecules about different molecular axes of water in the vicinity of uranyl ions have also been investigated and decreasing orientational mobility of water with increasing uranyl concentration has been found. However, it is observed that the orientational dynamics remains more or less the same whether we consider all the water molecules in the aqueous solution or only the solvation shell water molecules. The effect of temperature on the translational and orientational characteristics of the aqueous uranyl solutions has also been studied in detail.
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Affiliation(s)
- Manish Chopra
- Radiation Safety Systems Division, Bhabha Atomic Research Centre, Mumbai - 400 085, India
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Chen M, Lu X, Liu X, Hou Q, Zhu Y, Zhou H. Slow dynamics of water confined in Newton black films. Phys Chem Chem Phys 2015; 17:19183-93. [PMID: 26135223 DOI: 10.1039/c5cp02908b] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Slowdown of translational and reorientational dynamics of water confined in Newton black films (NBFs) is revealed by molecular dynamics simulations. As a film becomes thinner, both translational and reorientational dynamics become slower. The polarization of water molecules in the macroscopic electrostatic field across the NBF and the coordination of Na(+) ions and surfactant anionic groups around water molecules concertedly lead to slowdown of water dynamics. The polarization effect is obvious for water not coordinated by Na(+) ions, which exhibits reorientational dynamics depending on initial dipole orientations. Na(+) ions and surfactant anionic groups retard dynamics of surrounding water by decreasing the hydrogen bond exchange probability and increasing the viscosity of water. The dependences of translational and reorientational dynamics on coordination environments of water are similar. Dynamics of water in positions close to the interfaces of NBFs are mainly retarded by Na(+) ions and surfactant anionic groups, while the macroscopic polarization effect plays the main role in influencing water dynamics in positions far from the interfaces. This study sheds light on the improvement of knowledge about the water dynamics slowdown mechanism in similar environments like reverse micelles and lamellar structures.
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Affiliation(s)
- Meng Chen
- State Key Laboratory for Mineral Deposits Research, School of Earth Sciences and Engineering, Nanjing University, Nanjing, Jiangsu 210093, China.
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Rana MK, Chandra A. Wetting behavior of nonpolar nanotubes in simple dipolar liquids for varying nanotube diameter and solute-solvent interactions. J Chem Phys 2015; 142:034704. [PMID: 25612722 DOI: 10.1063/1.4905010] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Atomistic simulations of model nonpolar nanotubes in a Stockmayer liquid are carried out for varying nanotube diameter and nanotube-solvent interactions to investigate solvophobic interactions in generic dipolar solvents. We have considered model armchair type single-walled nonpolar nanotubes with increasing radii from (5,5) to (12,12). The interactions between solute and solvent molecules are modeled by the well-known Lennard-Jones and repulsive Weeks-Chandler-Andersen potentials. We have investigated the density profiles and microscopic arrangement of Stockmayer molecules, orientational profiles of their dipole vectors, time dependence of their occupation, and also the translational and rotational motion of solvent molecules in confined environments of the cylindrical nanopores and also in their external peripheral regions. The present results of structural and dynamical properties of Stockmayer molecules inside and near atomistically rough nonpolar surfaces including their wetting and dewetting behavior for varying interactions provide a more generic picture of solvophobic effects experienced by simple dipolar liquids without any specific interactions such as hydrogen bonds.
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Affiliation(s)
- Malay Kumar Rana
- 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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13
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Shevkunov SV. Water in extremely narrow planar pores with crystalline walls. 2. Thermodynamics. COLLOID JOURNAL 2014. [DOI: 10.1134/s1061933x14020100] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Wang D, Böckmann A, Dolenc J, Meier BH, van Gunsteren WF. On the behavior of water at subfreezing temperatures in a protein crystal: evidence of higher mobility than in bulk water. J Phys Chem B 2013; 117:11433-47. [PMID: 23998392 DOI: 10.1021/jp400655v] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
NMR experiments have shown that water molecules in the crystal of the protein Crh are still mobile at temperatures well below 273 K. In order to investigate this water anomaly, a molecular dynamics (MD) simulation study of crystalline Crh was carried out to determine the mobility of water in this crystal. The simulations were carried out at three temperatures, 150, 200, and 291 K. Simulations of bulk water at these temperatures were also done to obtain the properties of the simple point charge (SPC) water model used at these temperatures and to allow a comparison of the properties of water in the Crh crystal with those of bulk water at the same temperatures. According to the simulations, water is immobilized at 150 K both in crystal and in bulk water. As expected, at 291 K it diffuses and rotates more slowly in the protein crystal than in bulk water. However, at 200 K, the translational and rotational mobility of the water molecules is larger in the crystal than in bulk water. The enhancement of water mobility in the crystal at 200 K was further investigated by MD simulations in which the backbone or all protein atoms were positionally restrained, and in which additionally the electrostatic protein-water interactions were removed. Of these changes in the environment of the water molecules, rigidifying the protein backbones slightly enhanced water diffusion, while it slowed down rotation. In contrast, removal of electrostatic protein-water interactions did not change water diffusion but enhanced rotational motion significantly. Further investigations are required to delineate particular features of the protein crystal that induce the anomalous behavior of water at 200 K.
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Affiliation(s)
- Dongqi Wang
- Laboratory of Physical Chemistry, ETH Zürich , CH-8093 Zürich, Switzerland
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15
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Effect of surface hydrophobicity on the dynamics of water at the nanoscale confinement: A molecular dynamics simulation study. Chem Phys 2013. [DOI: 10.1016/j.chemphys.2013.06.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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16
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Rana MK, Chandra A. Solvation of fullerene and fulleride ion in liquid ammonia: Structure and dynamics of the solvation shells. J Chem Phys 2012; 137:134501. [DOI: 10.1063/1.4754852] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
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17
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Muntean SA, Gerasimov RA, Lyulin AV. Dynamics of Water Near Oxidized Polystyrene Films. MACROMOL THEOR SIMUL 2012. [DOI: 10.1002/mats.201200025] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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18
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Bandyopadhyay D, Choudhury N. Characterizing hydrophobicity at the nanoscale: A molecular dynamics simulation study. J Chem Phys 2012; 136:224505. [DOI: 10.1063/1.4725185] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
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19
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Malani A, Ayappa KG. Relaxation and jump dynamics of water at the mica interface. J Chem Phys 2012; 136:194701. [DOI: 10.1063/1.4717710] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
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