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Guimarães MN, M. de Almeida M, Marques JMC, Prudente FV. A thermodynamic view on the microsolvation of ions by rare gas: application to Li+ with argon. Phys Chem Chem Phys 2020; 22:10882-10892. [DOI: 10.1039/d0cp01283a] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Parallel tempering Monte Carlo calculations on the Li+Arn microsolvation clusters have shown that the two peaks appearing in the heat capacity curve as a function of temperature correspond to the melting of the second and first solvation shells.
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Affiliation(s)
- M. N. Guimarães
- Instituto de Física
- Universidade Federal da Bahia
- 40170-115 Salvador
- Brazil
| | - M. M. de Almeida
- Instituto de Física
- Universidade Federal da Bahia
- 40170-115 Salvador
- Brazil
| | - J. M. C. Marques
- CQC
- Department of Chemistry
- University of Coimbra
- 3004-535 Coimbra
- Portugal
| | - F. V. Prudente
- Instituto de Física
- Universidade Federal da Bahia
- 40170-115 Salvador
- Brazil
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2
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Shafiei M, von Domaros M, Bratko D, Luzar A. Anisotropic structure and dynamics of water under static electric fields. J Chem Phys 2019; 150:074505. [DOI: 10.1063/1.5079393] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Affiliation(s)
- Mahdi Shafiei
- Department of Chemistry, Virginia Commonwealth University, Richmond, Virginia 23284-2006, USA
| | - Michael von Domaros
- Department of Chemistry, University of California, Irvine, Irvine, California 92697, USA
| | - Dusan Bratko
- Department of Chemistry, Virginia Commonwealth University, Richmond, Virginia 23284-2006, USA
| | - Alenka Luzar
- Department of Chemistry, Virginia Commonwealth University, Richmond, Virginia 23284-2006, USA
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3
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Vibrational, energetic-dynamical and dissociation properties of water clusters in static electric fields: Non-equilibrium molecular-dynamics insights. Chem Phys Lett 2018. [DOI: 10.1016/j.cplett.2018.08.061] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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4
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Shevkunov SV. Water Structure in the Contact Layer on the Surface of Crystalline Silver Iodine. J STRUCT CHEM+ 2018. [DOI: 10.1134/s0022476618030137] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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5
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Miliordos E, Aprà E, Xantheas SS. A New, Dispersion-Driven Intermolecular Arrangement for the Benzene–Water Octamer Complex: Isomers and Analysis of their Vibrational Spectra. J Chem Theory Comput 2016; 12:4004-14. [DOI: 10.1021/acs.jctc.6b00668] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Evangelos Miliordos
- Physical
Sciences Division, Pacific Northwest National Laboratory, 902 Battelle
Boulevard, P.O. Box 999, MS K1-83, Richland, Washington 99352, United States
| | - Edoardo Aprà
- Environmental
Molecular Sciences Laboratory, Pacific Northwest National Laboratory, P.O. Box 999, Richland, Washington 99352, United States
| | - Sotiris S. Xantheas
- Physical
Sciences Division, Pacific Northwest National Laboratory, 902 Battelle
Boulevard, P.O. Box 999, MS K1-83, Richland, Washington 99352, United States
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6
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Cole WTS, Farrell JD, Wales DJ, Saykally RJ. Structure and torsional dynamics of the water octamer from THz laser spectroscopy near 215 μm. Science 2016; 352:1194-7. [PMID: 27257252 DOI: 10.1126/science.aad8625] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2015] [Accepted: 05/02/2016] [Indexed: 11/02/2022]
Affiliation(s)
- William T S Cole
- Department of Chemistry, University of California, Berkeley, CA 94705, USA
| | - James D Farrell
- Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, UK
| | - David J Wales
- Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, UK.
| | - Richard J Saykally
- Department of Chemistry, University of California, Berkeley, CA 94705, USA.
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7
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English NJ, Waldron CJ. Perspectives on external electric fields in molecular simulation: progress, prospects and challenges. Phys Chem Chem Phys 2016; 17:12407-40. [PMID: 25903011 DOI: 10.1039/c5cp00629e] [Citation(s) in RCA: 143] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
In this review, the application of a wide variety of external electric fields in molecular simulation shall be discussed, including time-varying and electromagnetic, as well as the utility and potential impact and prospects for exploitation of such simulations for real-world and industrial end use. In particular, non-equilibrium molecular dynamics will be discussed, as well as challenges in addressing adequate thermostatting and scaling field amplitudes to more experimentally relevant levels. Attention shall be devoted to recent progress and advances in external fields in ab initio molecular simulation and dynamics, as well as elusive challenges thereof (and, to some extent, for molecular dynamics from empirical potentials), such as timescales required to observe low-frequency and intensity field effects. The challenge of deterministic molecular dynamics in external fields in sampling phase space shall be discussed, along with prospects for application of fields in enhanced-sampling simulations. Finally, the application of external electric fields to a wide variety of aqueous, nanoscale and biological systems will be discussed, often motivated by the possibility of exploitation in real-world applications, which serve to underpin our molecular-level understanding of field effects in terms of microscopic mechanisms, and possibly with a view to control thereof.
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Affiliation(s)
- Niall J English
- School of Chemical and Bioprocess Engineering, University College Dublin, Belfield, Dublin 4, Ireland.
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8
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Gadre SR, Yeole SD, Sahu N. Quantum chemical investigations on molecular clusters. Chem Rev 2014; 114:12132-73. [PMID: 25341561 DOI: 10.1021/cr4006632] [Citation(s) in RCA: 147] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- Shridhar R Gadre
- Department of Chemistry, Indian Institute of Technology Kanpur , Kanpur 208 016, India
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9
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Chakrabarti D, Kusumaatmaja H, Rühle V, Wales DJ. Exploring energy landscapes: from molecular to mesoscopic systems. Phys Chem Chem Phys 2014; 16:5014-25. [PMID: 24067895 DOI: 10.1039/c3cp52603h] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
We review a comprehensive computational framework to survey the potential energy landscape for systems composed of rigid or partially rigid molecules. Illustrative case studies relevant to a wide range of molecular clusters and soft and condensed matter systems are discussed.
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Affiliation(s)
- Dwaipayan Chakrabarti
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK.
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10
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Qian Z, Fu Z, Wei G. Influence of electric fields on the structure and structure transition of water confined in a carbon nanotube. J Chem Phys 2014. [DOI: 10.1063/1.4871625] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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11
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12
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Shevkunov SV. Water vapor nucleation on a crystal surface in a strong electric field. COLLOID JOURNAL 2013. [DOI: 10.1134/s1061933x1304011x] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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13
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Richardson JO, Wales DJ, Althorpe SC, McLaughlin RP, Viant MR, Shih O, Saykally RJ. Investigation of Terahertz Vibration–Rotation Tunneling Spectra for the Water Octamer. J Phys Chem A 2013; 117:6960-6. [DOI: 10.1021/jp311306a] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Affiliation(s)
- Jeremy O. Richardson
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge,
CB2 1EW, United Kingdom
| | - David J. Wales
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge,
CB2 1EW, United Kingdom
| | - Stuart C. Althorpe
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge,
CB2 1EW, United Kingdom
| | - Ryan P. McLaughlin
- Department of Chemistry, University of California, Berkeley, California 94720,
United States
| | - Mark R. Viant
- Department of Chemistry, University of California, Berkeley, California 94720,
United States
| | - Orion Shih
- Department of Chemistry, University of California, Berkeley, California 94720,
United States
| | - Richard J. Saykally
- Department of Chemistry, University of California, Berkeley, California 94720,
United States
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14
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Structure of the floating water bridge and water in an electric field. Proc Natl Acad Sci U S A 2012; 109:16463-8. [PMID: 23010930 DOI: 10.1073/pnas.1210732109] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The floating water bridge phenomenon is a freestanding rope-shaped connection of pure liquid water, formed under the influence of a high potential difference (approximately 15 kV). Several recent spectroscopic, optical, and neutron scattering studies have suggested that the origin of the bridge is associated with the formation of anisotropic chains of water molecules in the liquid. In this work, high energy X-ray diffraction experiments have been performed on a series of floating water bridges as a function of applied voltage, bridge length, and position within the bridge. The two-dimensional X-ray scattering data showed no direction-dependence, indicating that the bulk water molecules do not exhibit any significant preferred orientation along the electric field. The only structural changes observed were those due to heating, and these effects were found to be the same as for bulk water. These X-ray scattering measurements are supported by molecular dynamics (MD) simulations which were performed under electric fields of 10(6) V/m and 10(9) V/m. Directional structure factor calculations were made from these simulations parallel and perpendicular to the E-field. The 10(6) V/m model showed no significant directional-dependence (anisotropy) in the structure factors. The 10(9) V/m model however, contained molecules aligned by the E-field, and had significant structural anisotropy.
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15
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Acosta-Gutiérrez S, Hernández-Rojas J, Bretón J, Llorente JMG, Wales DJ. Physical properties of small water clusters in low and moderate electric fields. J Chem Phys 2012; 135:124303. [PMID: 21974518 DOI: 10.1063/1.3640804] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Likely candidates for the lowest minima of water clusters (H(2)O)(N) for N ≤ 20 interacting with a uniform electric field strength in the range E ≤ 0.6 V/Å have been identified using basin-hopping global optimization. Two water-water model potentials were considered, namely TIP4P and the polarizable Dang-Chang potential. The two models produce some consistent results but also exhibit significant differences. The cluster internal energy and dipole moment indicate two varieties of topological transition in the structure of the global minimum as the field strength is increased. The first takes place at low field strengths (0.1 V/Å<E < 0.2 V/Å) and reorganizes the hydrogen-bonds to orient the water permanent dipoles along the field. The second type of transition occurs at larger field strengths (0.3 V/Å<E < 0.5 V/Å) and corresponds to an extensive structural reorganization, where several hydrogen-bonds break as the cluster stretches along the field direction, the larger clusters (N > 10) usually forming helical structures.
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Affiliation(s)
- S Acosta-Gutiérrez
- Departamento de Física Fundamental II and IUdEA, Universidad de La Laguna, 38205 Tenerife, Spain
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16
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Holden GL, Freeman DL. Monte Carlo Investigation of the Thermodynamic Properties of (H2O)n and (H2O)nH2 (n = 2−20) Clusters. J Phys Chem B 2011; 115:4725-44. [DOI: 10.1021/jp201082p] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Glen L. Holden
- Department of Chemistry, University of Rhode Island, Kingston, Rhode Island 02881, United States
| | - David L. Freeman
- Department of Chemistry, University of Rhode Island, Kingston, Rhode Island 02881, United States
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17
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Neela YI, Mahadevi AS, Sastry GN. Hydrogen Bonding in Water Clusters and Their Ionized Counterparts. J Phys Chem B 2010; 114:17162-71. [DOI: 10.1021/jp108634z] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Y. Indra Neela
- Molecular Modeling Group, Organic Chemical Sciences, Indian Institute of Chemical Technology, Tarnaka, Hyderabad 500 607, AP, India
| | - A. Subha Mahadevi
- Molecular Modeling Group, Organic Chemical Sciences, Indian Institute of Chemical Technology, Tarnaka, Hyderabad 500 607, AP, India
| | - G. Narahari Sastry
- Molecular Modeling Group, Organic Chemical Sciences, Indian Institute of Chemical Technology, Tarnaka, Hyderabad 500 607, AP, India
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18
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Denifl S, Zappa F, Mähr I, Mauracher A, Probst M, Urban J, Mach P, Bacher A, Bohme DK, Echt O, Märk TD, Scheier P. Ionization of doped helium nanodroplets: complexes of C60 with water clusters. J Chem Phys 2010; 132:234307. [PMID: 20572705 DOI: 10.1063/1.3436721] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Water clusters are known to undergo an autoprotonation reaction upon ionization by photons or electron impact, resulting in the formation of (H(2)O)(n)H(3)O(+). Ejection of OH cannot be quenched by near-threshold ionization; it is only partly quenched when clusters are complexed with inert gas atoms. Mass spectra recorded by electron ionization of water-doped helium droplets show that the helium matrix also fails to quench OH loss. The situation changes drastically when helium droplets are codoped with C(60). Charged C(60)-water complexes are predominantly unprotonated; C(60)(H(2)O)(4)(+) and (C(60))(2)(H(2)O)(4)(+) appear with enhanced abundance. Another intense ion series is due to C(60)(H(2)O)(n)OH(+); dehydrogenation is proposed to be initiated by charge transfer between the primary He(+) ion and C(60). The resulting electronically excited C(60)(+*) leads to the formation of a doubly charged C(60)-water complex either via emission of an Auger electron from C(60)(+*), or internal Penning ionization of the attached water complex, followed by charge separation within {C(60)(H(2)O)(n)}(2+). This mechanism would also explain previous observations of dehydrogenation reactions in doped helium droplets. Mass-analyzed ion kinetic energy scans reveal spontaneous (unimolecular) dissociation of C(60)(H(2)O)(n)(+). In addition to the loss of single water molecules, a prominent reaction channel yields bare C(60)(+) for sizes n=3, 4, or 6. Ab initio Hartree-Fock calculations for C(60)-water complexes reveal negligible charge transfer within neutral complexes. Cationic complexes are well described as water clusters weakly bound to C(60)(+). For n=3, 4, or 6, fissionlike desorption of the entire water complex from C(60)(H(2)O)(n)(+) energetically competes with the evaporation of a single water molecule.
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Affiliation(s)
- S Denifl
- Institut für Ionenphysik und Angewandte Physik and Center for Molecular Biosciences Innsbruck, Leopold Franzens Universität, 6020 Innsbruck, Austria
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19
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Hernández-Rojas J, Calvo F, Rabilloud F, Bretón J, Gomez Llorente JM. Modeling Water Clusters on Cationic Carbonaceous Seeds. J Phys Chem A 2010; 114:7267-74. [DOI: 10.1021/jp101584n] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- J. Hernández-Rojas
- Departamento de Física Fundamental II and IUdEA, Universidad de La Laguna, 38205, La Laguna, Tenerife, Spain, and LASIM, Université de Lyon and CNRS UMR 5579, Bât. A. Kastler, 43 Bd du 11 Novembre 1918, F69622 Villeurbanne Cedex, France
| | - F. Calvo
- Departamento de Física Fundamental II and IUdEA, Universidad de La Laguna, 38205, La Laguna, Tenerife, Spain, and LASIM, Université de Lyon and CNRS UMR 5579, Bât. A. Kastler, 43 Bd du 11 Novembre 1918, F69622 Villeurbanne Cedex, France
| | - F. Rabilloud
- Departamento de Física Fundamental II and IUdEA, Universidad de La Laguna, 38205, La Laguna, Tenerife, Spain, and LASIM, Université de Lyon and CNRS UMR 5579, Bât. A. Kastler, 43 Bd du 11 Novembre 1918, F69622 Villeurbanne Cedex, France
| | - J. Bretón
- Departamento de Física Fundamental II and IUdEA, Universidad de La Laguna, 38205, La Laguna, Tenerife, Spain, and LASIM, Université de Lyon and CNRS UMR 5579, Bât. A. Kastler, 43 Bd du 11 Novembre 1918, F69622 Villeurbanne Cedex, France
| | - J. M. Gomez Llorente
- Departamento de Física Fundamental II and IUdEA, Universidad de La Laguna, 38205, La Laguna, Tenerife, Spain, and LASIM, Université de Lyon and CNRS UMR 5579, Bât. A. Kastler, 43 Bd du 11 Novembre 1918, F69622 Villeurbanne Cedex, France
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20
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Luis D, López-Lemus J, Mayorga M. Electrodissociation of clathrate-like structures. MOLECULAR SIMULATION 2010. [DOI: 10.1080/08927021003628889] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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21
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González BS, Noya EG, Vega C, Sesé LM. Nuclear Quantum Effects in Water Clusters: The Role of the Molecular Flexibility. J Phys Chem B 2010; 114:2484-92. [DOI: 10.1021/jp910770y] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Briesta S. González
- Departamento Química Física I, Facultad de Ciencias Químicas, Universidad Complutense de Madrid, 28040 Madrid, Spain
| | - Eva G. Noya
- Departamento Química Física I, Facultad de Ciencias Químicas, Universidad Complutense de Madrid, 28040 Madrid, Spain
| | - Carlos Vega
- Departamento Química Física I, Facultad de Ciencias Químicas, Universidad Complutense de Madrid, 28040 Madrid, Spain
| | - Luis M. Sesé
- Departamento Ciencias y Técnicas Fisicoquímicas, Facultad de Ciencias, UNED, Paseo Senda del Rey 9, 28040 Madrid, Spain
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22
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Asare E, Musah AR, Curotto E, Freeman DL, Doll JD. The thermodynamic and ground state properties of the TIP4P water octamer. J Chem Phys 2009; 131:184508. [DOI: 10.1063/1.3259047] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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23
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Bolton K, Johansson E, Jönsson L, Ahlström P. Simulation of water clusters in vapour, alkanes and polyethylenes. MOLECULAR SIMULATION 2009. [DOI: 10.1080/08927020902787804] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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24
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Calvo F, Dugourd P. Folding of gas-phase polyalanines in a static electric field: alignment, deformations, and polarization effects. Biophys J 2008; 95:18-32. [PMID: 18223004 PMCID: PMC2426642 DOI: 10.1529/biophysj.107.124685] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2007] [Accepted: 12/28/2007] [Indexed: 11/18/2022] Open
Abstract
Monte Carlo simulations of the temperature-induced unfolding of small gas-phase polyalanines in a static, homogeneous electric field are reported, based on the AMBER ff96 force field. The peptides exhibit a structural transition from the native alpha-helix state to entropically favored beta-sheet conformations, before eventually turning to extended coil at higher temperatures. Upon switching the electric field, the molecules undergo preferential alignment of their dipole moment vector toward the field axis and a shift of the alpha-beta transition to higher temperatures. At higher field strengths (>10(8) V/m) the molecules stretch and the alpha-beta and beta-coil transitions merge. A simple three-state model is shown to account for the observed behavior. Under even higher fields, density functional theory calculations and a polarizable force field both show that electronic rearrangements tend to further increase the dipole moment, polarization effects being approximately half in magnitude with respect to stretching effect. Finally a tentative (temperature, field-strength) phase diagram is sketched.
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Affiliation(s)
- F Calvo
- Centre National de la Recherche Scientifique, Laboratoire de Spectrometrie Ionique et Moleculaire, Université de Lyon, Université Lyon 1, Villeurbanne, France.
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25
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Rai D, Kulkarni AD, Gejji SP, Pathak RK. Water clusters (H2O)n, n=6–8, in external electric fields. J Chem Phys 2008; 128:034310. [DOI: 10.1063/1.2816565] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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26
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Johansson E, Bolton K, Ahlström P. Water absorption in polyethylene under external electric fields. J Chem Phys 2007; 127:024902. [PMID: 17640146 DOI: 10.1063/1.2750340] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Monte Carlo simulations of the solubility and structure of water in polyethylene in thermodynamic equilibrium with liquid water were performed in external fields ranging from 2 x 10(5) to 4 x 10(9) V/m. For a given equilibrium temperature and pressure, the water solubility decreases at higher fields. This occurs since it is energetically favorable for water molecules to be in the pure water phase than in the polyethylene matrix at high field strengths, and results in an increased density in the water phase. However, fields relevant to high voltage conduction (in the absence of defects that can lead to large local field strengths) do not change the solubility. In addition, at large fields the number of water clusters decreases for all cluster sizes. The rate of decrease is highest for large clusters, and a larger fraction of water molecules exist as monomers in the polyethylene matrix at high fields. Large fields also cause alignment of the water molecules, which leads to more clusters with linear topologies and hence an increase in the cluster radius of gyration.
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Affiliation(s)
- E Johansson
- School of Engineering, University College of Borås, SE-501 90 Borås, Sweden
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27
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James T, Wales DJ, Hernández Rojas J. Energy landscapes for water clusters in a uniform electric field. J Chem Phys 2007; 126:054506. [PMID: 17302484 DOI: 10.1063/1.2429659] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
The behavior of small water clusters, (H2O)n, n=2-5 and n=8, in a uniform electric field is investigated for three related rigid-body models. Changes in the properties of the low-lying potential energy minima and the rearrangement pathways between them are examined. Results for certain structural transitions are compared with recent ab initio calculations. The models are found to give qualitatively similar trends, and there is some evidence that as the applied field strength is increased the quantitative differences between the models are also reduced.
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Affiliation(s)
- Tim James
- University Chemical Laboratories, Lensfield Road, Cambridge CB2 1EW, United Kingdom
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