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Water and Ion Dynamics in Confined Media: A Multi-Scale Study of the Clay/Water Interface. COLLOIDS AND INTERFACES 2021. [DOI: 10.3390/colloids5020034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
This review details a large panel of experimental studies (Inelastic Neutron Scattering, Quasi-Elastic Neutron Scattering, Nuclear Magnetic Resonance relaxometry, Pulsed-Gradient Spin-Echo attenuation, Nuclear Magnetic Resonance Imaging, macroscopic diffusion experiments) used recently to probe, over a large distribution of characteristic times (from pico-second up to days), the dynamical properties of water molecules and neutralizing cations diffusing within clay/water interfacial media. The purpose of this review is not to describe these various experimental methods in detail but, rather, to investigate the specific dynamical information obtained by each of them concerning these clay/water interfacial media. In addition, this review also illustrates the various numerical methods (quantum Density Functional Theory, classical Molecular Dynamics, Brownian Dynamics, macroscopic differential equations) used to interpret these various experimental data by analyzing the corresponding multi-scale dynamical processes. The purpose of this multi-scale study is to perform a bottom-up analysis of the dynamical properties of confined ions and water molecules, by using complementary experimental and numerical studies covering a broad range of diffusion times (between pico-seconds up to days) and corresponding diffusion lengths (between Angstroms and centimeters). In the context of such a bottom-up approach, the numerical modeling of the dynamical properties of the diffusing probes is based on experimental or numerical investigations performed on a smaller scale, thus avoiding the use of empirical or fitted parameters.
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Mitra S, Sharma VK, Mukhopadhyay R. Diffusion of confined fluids in microporous zeolites and clay materials. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2021; 84:066501. [PMID: 33740783 DOI: 10.1088/1361-6633/abf085] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Accepted: 03/19/2021] [Indexed: 06/12/2023]
Abstract
Fluids exhibit remarkable variation in their structural and dynamic properties when they are confined at the nanoscopic scale. Various factors, including geometric restriction, the size and shape of the guest molecules, the topology of the host, and guest-host interactions, are responsible for the alterations in these properties. Due to their porous structures, aluminosilicates provide a suitable host system for studying the diffusion of sorbates in confinement. Zeolites and clays are two classes of the aluminosilicate family, comprising very ordered porous or layered structures. Zeolitic materials are important due to their high catalytic activity and molecular sieving properties. Guest molecules adsorbed by zeolites display many interesting features including unidimensional diffusion, non-isotropic rotation, preferred orientation and levitation effects, depending on the guest and host characteristics. These are useful for the separation of hydrocarbons which commonly exist as mixtures in nature. Similarly, clay materials have found application in catalysis, desalination, enhanced oil recovery, and isolation barriers used in radioactive waste disposal. It has been shown that the bonding interactions, level of hydration, interlayer spacing, and number of charge-balancing cations are the important factors that determine the nature of diffusion of water molecules in clays. Here, we present a review of the current status of the diffusion mechanisms of various adsorbed species in different microporous zeolites and clays, as investigated using quasielastic neutron scattering and classical molecular dynamics simulation techniques. It is impossible to write an exhaustive review of the subject matter, as it has been explored over several decades and involves many research topics. However, an effort is made to cover the relevant issues specific to the dynamics of different molecules in microporous zeolites and clay materials and to highlight a variety of interesting features that are important for both practical applications and fundamental aspects.
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Affiliation(s)
- S Mitra
- Solid State Physics Division, Bhabha Atomic Research Centre, Mumbai 400085, India
- Homi Bhabha National Institute, Anushaktinagar, Mumbai 400094, India
| | - V K Sharma
- Solid State Physics Division, Bhabha Atomic Research Centre, Mumbai 400085, India
- Homi Bhabha National Institute, Anushaktinagar, Mumbai 400094, India
| | - R Mukhopadhyay
- Solid State Physics Division, Bhabha Atomic Research Centre, Mumbai 400085, India
- Homi Bhabha National Institute, Anushaktinagar, Mumbai 400094, India
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3
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Ok S, Hwang B, Liu T, Welch S, Sheets JM, Cole DR, Liu KH, Mou CY. Fluid Behavior in Nanoporous Silica. Front Chem 2020; 8:734. [PMID: 33005606 PMCID: PMC7485247 DOI: 10.3389/fchem.2020.00734] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Accepted: 07/16/2020] [Indexed: 11/13/2022] Open
Abstract
We investigate dynamics of water (H2O) and methanol (CH3OH and CH3OD) inside mesoporous silica materials with pore diameters of 4.0, 2.5, and 1.5 nm using low-field (LF) nuclear magnetic resonance (NMR) relaxometry. Experiments were conducted to test the effects of pore size, pore volume, type of fluid, fluid/solid ratio, and temperature on fluid dynamics. Longitudinal relaxation times (T1) and transverse relaxation times (T2) were obtained for the above systems. We observe an increasing deviation in confined fluid behavior compared to that of bulk fluid with decreasing fluid-to-solid ratio. Our results show that the surface area-to-volume ratio is a critical parameter compared to pore diameter in the relaxation dynamics of confined water. An increase in temperature for the range between 25 and 50°C studied did not influence T2 times of confined water significantly. However, when the temperature was increased, T1 times of water confined in both silica-2.5 nm and silica-1.5 nm increased, while those of water in silica-4.0 nm did not change. Reductions in both T1 and T2 values as a function of fluid-to-solid ratio were independent of confined fluid species studied here. The parameter T1/T2 indicates that H2O interacts more strongly with the pore walls of silica-4.0 nm than CH3OH and CH3OD.
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Affiliation(s)
- Salim Ok
- School of Earth Sciences, The Ohio State University, Columbus, OH, United States
| | - Bohyun Hwang
- School of Earth Sciences, The Ohio State University, Columbus, OH, United States
| | - Tingting Liu
- School of Earth Sciences, The Ohio State University, Columbus, OH, United States
| | - Susan Welch
- School of Earth Sciences, The Ohio State University, Columbus, OH, United States
| | - Julia M. Sheets
- School of Earth Sciences, The Ohio State University, Columbus, OH, United States
| | - David R. Cole
- School of Earth Sciences, The Ohio State University, Columbus, OH, United States
- Department of Chemistry, The Ohio State University, Columbus, OH, United States
| | - Kao-Hsiang Liu
- Shull Wollan Center-A Joint Institute for Neutron Sciences, Oak Ridge National Laboratory, Oak Ridge, TN, United States
| | - Chung-Yuan Mou
- Department of Chemistry, National Taiwan University, Taipei, Taiwan
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Shinohara Y, Dmowski W, Iwashita T, Wu B, Ishikawa D, Baron AQR, Egami T. Viscosity and real-space molecular motion of water: Observation with inelastic x-ray scattering. Phys Rev E 2018; 98:022604. [PMID: 30253607 DOI: 10.1103/physreve.98.022604] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2018] [Indexed: 11/07/2022]
Abstract
Even though viscosity is one of the fundamental properties of liquids, its microscopic origin is not fully understood. We determined the spatial and temporal correlation of molecular motions of water near room temperature and its temperature variation on a picosecond timescale and a subnanometer spatial scale, through high-resolution inelastic x-ray scattering measurement. The results, expressed in terms of the time-dependent pair correlation function called the Van Hove function, show that the timescale of the decay of the molecular correlation is directly related to the Maxwell relaxation time near room temperature, which is proportional to viscosity. This conclusion validates our earlier finding that the topological changes in atomic or molecular connectivity are the origin of viscosity in liquids.
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Affiliation(s)
- Yuya Shinohara
- Shull-Wollan Center, University of Tennessee and Oak Ridge National Laboratory, Oak Ridge, Tennessee, 37831, USA and Department of Materials Science and Engineering, University of Tennessee, Knoxville, Tennessee, 37996, USA
| | - Wojciech Dmowski
- Shull-Wollan Center, University of Tennessee and Oak Ridge National Laboratory, Oak Ridge, Tennessee, 37831, USA and Department of Materials Science and Engineering, University of Tennessee, Knoxville, Tennessee, 37996, USA
| | - Takuya Iwashita
- Department of Integrated Science and Technology, Oita University, Dannoharu, Oita 870-1192, Japan
| | - Bin Wu
- Oak Ridge National Laboratory, Oak Ridge, Tennessee, 37831, USA
| | - Daisuke Ishikawa
- Materials Dynamics Laboratory, RIKEN SPring-8 Center, RIKEN, Sayo, Hyogo 679-5148, Japan.,Research and Utilization Divition, Japan Synchrotron Radiation Research Institute (JASRI), Sayo, Hyogo 679-5198, Japan
| | - Alfred Q R Baron
- Materials Dynamics Laboratory, RIKEN SPring-8 Center, RIKEN, Sayo, Hyogo 679-5148, Japan
| | - Takeshi Egami
- Shull-Wollan Center, University of Tennessee and Oak Ridge National Laboratory, Oak Ridge, Tennessee, 37831, USA and Department of Materials Science and Engineering, University of Tennessee, Knoxville, Tennessee, 37996, USA.,Oak Ridge National Laboratory, Oak Ridge, Tennessee, 37831, USA.,Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996, USA
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5
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Perakis F, Camisasca G, Lane TJ, Späh A, Wikfeldt KT, Sellberg JA, Lehmkühler F, Pathak H, Kim KH, Amann-Winkel K, Schreck S, Song S, Sato T, Sikorski M, Eilert A, McQueen T, Ogasawara H, Nordlund D, Roseker W, Koralek J, Nelson S, Hart P, Alonso-Mori R, Feng Y, Zhu D, Robert A, Grübel G, Pettersson LGM, Nilsson A. Coherent X-rays reveal the influence of cage effects on ultrafast water dynamics. Nat Commun 2018; 9:1917. [PMID: 29765052 PMCID: PMC5953967 DOI: 10.1038/s41467-018-04330-5] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2017] [Accepted: 04/19/2018] [Indexed: 11/13/2022] Open
Abstract
The dynamics of liquid water feature a variety of time scales, ranging from extremely fast ballistic-like thermal motion, to slower molecular diffusion and hydrogen-bond rearrangements. Here, we utilize coherent X-ray pulses to investigate the sub-100 fs equilibrium dynamics of water from ambient conditions down to supercooled temperatures. This novel approach utilizes the inherent capability of X-ray speckle visibility spectroscopy to measure equilibrium intermolecular dynamics with lengthscale selectivity, by measuring oxygen motion in momentum space. The observed decay of the speckle contrast at the first diffraction peak, which reflects tetrahedral coordination, is attributed to motion on a molecular scale within the first 120 fs. Through comparison with molecular dynamics simulations, we conclude that the slowing down upon cooling from 328 K down to 253 K is not due to simple thermal ballistic-like motion, but that cage effects play an important role even on timescales over 25 fs due to hydrogen-bonding.
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Affiliation(s)
- Fivos Perakis
- Department of Physics, AlbaNova University Center, Stockholm University, S-106 91, Stockholm, Sweden.
- SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California, CA, 94025, USA.
| | - Gaia Camisasca
- Department of Physics, AlbaNova University Center, Stockholm University, S-106 91, Stockholm, Sweden
| | - Thomas J Lane
- SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California, CA, 94025, USA
| | - Alexander Späh
- Department of Physics, AlbaNova University Center, Stockholm University, S-106 91, Stockholm, Sweden
| | - Kjartan Thor Wikfeldt
- Department of Physics, AlbaNova University Center, Stockholm University, S-106 91, Stockholm, Sweden
| | - Jonas A Sellberg
- Biomedical and X-ray Physics, Department of Applied Physics, AlbaNova University Center, KTH Royal Institute of Technology, S-10691, Stockholm, Sweden
| | - Felix Lehmkühler
- Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607, Hamburg, Germany
- Hamburg Centre for Ultrafast Imaging, Luruper Chaussee 149, 22761, Hamburg, Germany
| | - Harshad Pathak
- Department of Physics, AlbaNova University Center, Stockholm University, S-106 91, Stockholm, Sweden
| | - Kyung Hwan Kim
- Department of Physics, AlbaNova University Center, Stockholm University, S-106 91, Stockholm, Sweden
| | - Katrin Amann-Winkel
- Department of Physics, AlbaNova University Center, Stockholm University, S-106 91, Stockholm, Sweden
| | - Simon Schreck
- Department of Physics, AlbaNova University Center, Stockholm University, S-106 91, Stockholm, Sweden
| | - Sanghoon Song
- SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California, CA, 94025, USA
| | - Takahiro Sato
- SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California, CA, 94025, USA
| | - Marcin Sikorski
- SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California, CA, 94025, USA
- European XFEL, Holzkoppel 4, 22869, Schenefeld, Germany
| | - Andre Eilert
- SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California, CA, 94025, USA
| | - Trevor McQueen
- SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California, CA, 94025, USA
| | - Hirohito Ogasawara
- SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California, CA, 94025, USA
| | - Dennis Nordlund
- SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California, CA, 94025, USA
| | - Wojciech Roseker
- Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607, Hamburg, Germany
| | - Jake Koralek
- SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California, CA, 94025, USA
| | - Silke Nelson
- SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California, CA, 94025, USA
| | - Philip Hart
- SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California, CA, 94025, USA
| | - Roberto Alonso-Mori
- SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California, CA, 94025, USA
| | - Yiping Feng
- SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California, CA, 94025, USA
| | - Diling Zhu
- SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California, CA, 94025, USA
| | - Aymeric Robert
- SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California, CA, 94025, USA
| | - Gerhard Grübel
- Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607, Hamburg, Germany
- Hamburg Centre for Ultrafast Imaging, Luruper Chaussee 149, 22761, Hamburg, Germany
| | - Lars G M Pettersson
- Department of Physics, AlbaNova University Center, Stockholm University, S-106 91, Stockholm, Sweden
| | - Anders Nilsson
- Department of Physics, AlbaNova University Center, Stockholm University, S-106 91, Stockholm, Sweden.
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Tamtögl A, Davey B, Ward DJ, Jardine AP, Ellis J, Allison W. Polarisation in spin-echo experiments: Multi-point and lock-in measurements. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2018; 89:023902. [PMID: 29495876 DOI: 10.1063/1.5017276] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Spin-echo instruments are typically used to measure diffusive processes and the dynamics and motion in samples on ps and ns time scales. A key aspect of the spin-echo technique is to determine the polarisation of a particle beam. We present two methods for measuring the spin polarisation in spin-echo experiments. The current method in use is based on taking a number of discrete readings. The implementation of a new method involves continuously rotating the spin and measuring its polarisation after being scattered from the sample. A control system running on a microcontroller is used to perform the spin rotation and to calculate the polarisation of the scattered beam based on a lock-in amplifier. First experimental tests of the method on a helium spin-echo spectrometer show that it is clearly working and that it has advantages over the discrete approach, i.e., it can track changes of the beam properties throughout the experiment. Moreover, we show that real-time numerical simulations can perfectly describe a complex experiment and can be easily used to develop improved experimental methods prior to a first hardware implementation.
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Affiliation(s)
- Anton Tamtögl
- Cavendish Laboratory, J. J. Thompson Avenue, Cambridge CB3 0HE, United Kingdom
| | - Benjamin Davey
- Cavendish Laboratory, J. J. Thompson Avenue, Cambridge CB3 0HE, United Kingdom
| | - David J Ward
- Cavendish Laboratory, J. J. Thompson Avenue, Cambridge CB3 0HE, United Kingdom
| | - Andrew P Jardine
- Cavendish Laboratory, J. J. Thompson Avenue, Cambridge CB3 0HE, United Kingdom
| | - John Ellis
- Cavendish Laboratory, J. J. Thompson Avenue, Cambridge CB3 0HE, United Kingdom
| | - William Allison
- Cavendish Laboratory, J. J. Thompson Avenue, Cambridge CB3 0HE, United Kingdom
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7
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Swenson J. Possible relations between supercooled and glassy confined water and amorphous bulk ice. Phys Chem Chem Phys 2018; 20:30095-30103. [DOI: 10.1039/c8cp05688a] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
A proposed relaxation scenario of bulk water based on studies of confined water and low density amorphous ice.
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Affiliation(s)
- Jan Swenson
- Department of Physics, Chalmers University of Technology
- SE-412 96 Göteborg
- Sweden
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8
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Restraining Na-Montmorillonite Delamination in Water by Adsorption of Sodium Dodecyl Sulfate or Octadecyl Trimethyl Ammonium Chloride on the Edges. MINERALS 2016. [DOI: 10.3390/min6030087] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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9
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Arbe A, Moreno AJ, Allgaier J, Ivanova O, Fouquet P, Colmenero J, Richter D. Role of Dynamic Asymmetry on the Collective Dynamics of Comblike Polymers: Insights from Neutron Spin-Echo Experiments and Coarse-Grained Molecular Dynamics Simulations. Macromolecules 2016. [DOI: 10.1021/acs.macromol.6b00931] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Arantxa Arbe
- Materials Physics Center (MPC), Centro de Física de Materiales (CFM), CSIC−UPV/EHU, Paseo Manuel de Lardizabal 5, 20018 San Sebastián, Spain
- Jülich Centre for Neutron Science and Institut for Complex Systems, Forschungszentrum Jülich GmbH, D-52425 Jülich, Germany
- Jülich Centre for Neutron Science, Forschungszentrum Jülich GmbH, Outstation at Heinz
Maier-Leibnitz Zentrum, Lichtenbergstr.1, 85747 Garching, Germany
- Institut Laue−Langevin, CS 20156, 38042 Grenoble, Cedex 9, France
- Departamento de Física de Materiales, UPV/EHU, Apartado 1072, 20080 San Sebastián, Spain
| | - Angel J. Moreno
- Materials Physics Center (MPC), Centro de Física de Materiales (CFM), CSIC−UPV/EHU, Paseo Manuel de Lardizabal 5, 20018 San Sebastián, Spain
- Jülich Centre for Neutron Science and Institut for Complex Systems, Forschungszentrum Jülich GmbH, D-52425 Jülich, Germany
- Jülich Centre for Neutron Science, Forschungszentrum Jülich GmbH, Outstation at Heinz
Maier-Leibnitz Zentrum, Lichtenbergstr.1, 85747 Garching, Germany
- Institut Laue−Langevin, CS 20156, 38042 Grenoble, Cedex 9, France
- Departamento de Física de Materiales, UPV/EHU, Apartado 1072, 20080 San Sebastián, Spain
| | - Jürgen Allgaier
- Materials Physics Center (MPC), Centro de Física de Materiales (CFM), CSIC−UPV/EHU, Paseo Manuel de Lardizabal 5, 20018 San Sebastián, Spain
- Jülich Centre for Neutron Science and Institut for Complex Systems, Forschungszentrum Jülich GmbH, D-52425 Jülich, Germany
- Jülich Centre for Neutron Science, Forschungszentrum Jülich GmbH, Outstation at Heinz
Maier-Leibnitz Zentrum, Lichtenbergstr.1, 85747 Garching, Germany
- Institut Laue−Langevin, CS 20156, 38042 Grenoble, Cedex 9, France
- Departamento de Física de Materiales, UPV/EHU, Apartado 1072, 20080 San Sebastián, Spain
| | - Oxana Ivanova
- Materials Physics Center (MPC), Centro de Física de Materiales (CFM), CSIC−UPV/EHU, Paseo Manuel de Lardizabal 5, 20018 San Sebastián, Spain
- Jülich Centre for Neutron Science and Institut for Complex Systems, Forschungszentrum Jülich GmbH, D-52425 Jülich, Germany
- Jülich Centre for Neutron Science, Forschungszentrum Jülich GmbH, Outstation at Heinz
Maier-Leibnitz Zentrum, Lichtenbergstr.1, 85747 Garching, Germany
- Institut Laue−Langevin, CS 20156, 38042 Grenoble, Cedex 9, France
- Departamento de Física de Materiales, UPV/EHU, Apartado 1072, 20080 San Sebastián, Spain
| | - Peter Fouquet
- Materials Physics Center (MPC), Centro de Física de Materiales (CFM), CSIC−UPV/EHU, Paseo Manuel de Lardizabal 5, 20018 San Sebastián, Spain
- Jülich Centre for Neutron Science and Institut for Complex Systems, Forschungszentrum Jülich GmbH, D-52425 Jülich, Germany
- Jülich Centre for Neutron Science, Forschungszentrum Jülich GmbH, Outstation at Heinz
Maier-Leibnitz Zentrum, Lichtenbergstr.1, 85747 Garching, Germany
- Institut Laue−Langevin, CS 20156, 38042 Grenoble, Cedex 9, France
- Departamento de Física de Materiales, UPV/EHU, Apartado 1072, 20080 San Sebastián, Spain
| | - Juan Colmenero
- Materials Physics Center (MPC), Centro de Física de Materiales (CFM), CSIC−UPV/EHU, Paseo Manuel de Lardizabal 5, 20018 San Sebastián, Spain
- Jülich Centre for Neutron Science and Institut for Complex Systems, Forschungszentrum Jülich GmbH, D-52425 Jülich, Germany
- Jülich Centre for Neutron Science, Forschungszentrum Jülich GmbH, Outstation at Heinz
Maier-Leibnitz Zentrum, Lichtenbergstr.1, 85747 Garching, Germany
- Institut Laue−Langevin, CS 20156, 38042 Grenoble, Cedex 9, France
- Departamento de Física de Materiales, UPV/EHU, Apartado 1072, 20080 San Sebastián, Spain
| | - Dieter Richter
- Materials Physics Center (MPC), Centro de Física de Materiales (CFM), CSIC−UPV/EHU, Paseo Manuel de Lardizabal 5, 20018 San Sebastián, Spain
- Jülich Centre for Neutron Science and Institut for Complex Systems, Forschungszentrum Jülich GmbH, D-52425 Jülich, Germany
- Jülich Centre for Neutron Science, Forschungszentrum Jülich GmbH, Outstation at Heinz
Maier-Leibnitz Zentrum, Lichtenbergstr.1, 85747 Garching, Germany
- Institut Laue−Langevin, CS 20156, 38042 Grenoble, Cedex 9, France
- Departamento de Física de Materiales, UPV/EHU, Apartado 1072, 20080 San Sebastián, Spain
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10
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Indra S, Biswas R. Hydrogen-bond dynamics of water in presence of an amphiphile, tetramethylurea: signature of confinement-induced effects. MOLECULAR SIMULATION 2014. [DOI: 10.1080/08927022.2014.965705] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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11
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Elamin K, Björklund J, Nyhlén F, Yttergren M, Mårtensson L, Swenson J. Glass transition and relaxation dynamics of propylene glycol–water solutions confined in clay. J Chem Phys 2014; 141:034505. [DOI: 10.1063/1.4889742] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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12
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Suzuki A, Yui H. Crystallization of confined water pools with radii greater than 1 nm in AOT reverse micelles. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2014; 30:7274-7282. [PMID: 24885023 DOI: 10.1021/la501210t] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Freezing of water pools inside aerosol sodium bis(2-ethylhexyl) sulfosuccinate (AOT) reverse micelles has been investigated. Previous freezing experiments suffer from collision and fusion of AOT micelles and resultant loss of water from the water pool by shedding out during the cooling process. These phenomena have restricted the formation of ice to only when the radius of the water pool (Rw) is below 1 nm, and only amorphous ice has been observed. To overcome the size limitation, a combination of rapid cooling and a custom-made cell allowing thin sample loading is applied for instantaneous and homogeneous freezing. The freezing process is monitored with attenuated total reflection infrared spectroscopy (ATR-IR) measurements. A cooling rate of ca. -100 K/min and a sample thickness of ca. 50 μm overcomes the limitations mentioned above and allows the crystallization of water pools with larger radii (Rw > 1 nm). The corresponding ATR-IR spectra of the frozen water pools with Rw < 2.0 nm show similar features to the spectrum of metastable cubic ice (Ic). Further increase of the radius of the water pool (Rw > 2.0 nm), unfortunately, drastically decreased the integrated area of the ν(OH) band observed just after freezing, indicating the breakup of the micellar structure and shedding out of the water pool. In addition, it was revealed that Ic ice can also be formed in flexible organic self-assembled AOT reverse micelles for at least Rw ≤ ca. 2 nm, as well as in inorganic and solid materials with a pore radius of ca. 2 nm. The dependence of the phase transition temperature on the curvature of the reverse micelles is discussed from the viewpoint of the Gibbs-Thomson effect.
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Affiliation(s)
- Akira Suzuki
- Department of Chemistry, Faculty of Science, Tokyo University of Science , 1-3 Kagurazaka, Shinjuku-city, Tokyo 162-8601, Japan
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13
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Sun Q, Zhou C, Yue Y, Hu L. A Direct Link between the Fragile-to-Strong Transition and Relaxation in Supercooled Liquids. J Phys Chem Lett 2014; 5:1170-1174. [PMID: 26274466 DOI: 10.1021/jz500239w] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
It is known that both the fragile-to-strong (F-S) transition and relaxation processes occur in numerous supercooled liquids upon cooling toward the glass transition temperature. The key question is whether and how these two dynamic processes are correlated. Here, we show a direct link between the two processes for both metallic glass-forming liquids (MGFLs) with different fragilities and also for nonmetallic glass-forming liquids. By comparing the F-S transition extent parameter f with the parameter r that characterizes the competition between the α and the slow β relaxations, we have discovered a negative exponential connection between the two parameters of supercooled liquids. The finding indicates that the slow β relaxation plays a dominant role in the F-S transition. This work provides new insight into the microscopic mechanism of the F-S transition and creates a strong basis for predicting whether and to what extent the F-S transition occurs in supercooled liquids.
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Affiliation(s)
| | | | - Yuanzheng Yue
- ‡Section of Chemistry, Aalborg University, DK-9000 Aalborg, Denmark
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Anovitz LM, Mamontov E, ben Ishai P, Kolesnikov AI. Anisotropic dynamics of water ultraconfined in macroscopically oriented channels of single-crystal beryl: a multifrequency analysis. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2013; 88:052306. [PMID: 24329263 DOI: 10.1103/physreve.88.052306] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2013] [Revised: 08/09/2013] [Indexed: 06/03/2023]
Abstract
The properties of fluids can be significantly altered by the geometry of their confining environments. While there has been significant work on the properties of such confined fluids, the properties of fluids under ultraconfinement, environments where, at least in one plane, the dimensions of the confining environment are similar to that of the confined molecule, have not been investigated. This paper investigates the dynamic properties of water in beryl (Be(3)Al(2)Si(6)O(18)), the structure of which contains approximately 5-Å-diam channels parallel to the c axis. Three techniques, inelastic neutron scattering, quasielastic neutron scattering, and dielectric spectroscopy, have been used to quantify these properties over a dynamic range covering approximately 16 orders of magnitude. Because beryl can be obtained in large single crystals we were able to quantify directional variations, perpendicular and parallel to the channel directions, in the dynamics of the confined fluid. These are significantly anisotropic and, somewhat counterintuitively, show that vibrations parallel to the c-axis channels are significantly more hindered than those perpendicular to the channels. The effective potential for vibrations in the c direction is harder than the potential in directions perpendicular to it. There is evidence of single-file diffusion of water molecules along the channels at higher temperatures, but below 150 K this diffusion is strongly suppressed. No such suppression, however, has been observed in the channel-perpendicular direction. Inelastic neutron scattering spectra include an intramolecular stretching O-H peak at ~465 meV. As this is nearly coincident with that known for free water molecules and approximately 30 meV higher than that in liquid water or ice, this suggests that there is no hydrogen bonding constraining vibrations between the channel water and the beryl structure. However, dielectric spectroscopic measurements at higher temperatures and lower frequencies yield an activation energy for the dipole reorientation of 16.4 ± 0.14 kJ/mol, close to the energy required to break a hydrogen bond in bulk water. This may suggest the presence of some other form of bonding between the water molecules and the structure, but the resolution of the apparent contradiction between the inelastic neutron and dielectric spectroscopic results remains uncertain.
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Affiliation(s)
- Lawrence M Anovitz
- Chemical Sciences Division, MS 6110, P.O. Box 2008, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6110, USA
| | - Eugene Mamontov
- Chemical and Engineering Materials Division, MS 6473, P.O. Box 2008, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6473, USA
| | - Paul ben Ishai
- Department of Applied Physics, The Hebrew University of Jerusalem, Givat Ram, 91904 Jerusalem, Israel
| | - Alexander I Kolesnikov
- Chemical and Engineering Materials Division, MS 6473, P.O. Box 2008, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6473, USA
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15
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Mitra S, Prabhudesai SA, Chakrabarty D, Sharma VK, Vicente MA, Embs JP, Mukhopadhyay R. Dynamics of water in synthetic saponite clays: effect of trivalent ion substitution. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2013; 87:062317. [PMID: 23848685 DOI: 10.1103/physreve.87.062317] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2013] [Indexed: 06/02/2023]
Abstract
Saponite clay belongs to the phyllosilicate family and is comprised of layers of Si(IV) tetrahedra and Al(III) or Mg(II) octahedra with definite interlayer spacing. In these systems, the trivalent ion substitutions in the tetrahedral layers lead to negative charge on the layers. Here we report the dynamics of water contained in [Si(6.97)Al(1.03)][Ni(6.00)]O(20)(OH)(4)[Na(1.03)]·28H(2)O (SAP-1) and [Si(7.13)Fe(0.86)][Ni(6.00)]O(20)(OH)(4)[Na(0.86)]·14H(2)O (SAP-2) saponite clays in the temperature range 200-310 K as studied by quasielastic neutron scattering technique. Particularly the effect of the ion substitution towards the dynamics of water is addressed here. Data analysis is carried out using the relaxing cage model. The existence of distribution in relaxation times indicated that the water molecules in saponite clay have a different local environment which leads to complex diffusion behavior. It is found that water exists in a supercooled state in the temperature range up to 235 K. However, some of the water molecules are found to be immobile in the temperature range 240-285 K. The fraction of immobile water decreases with increase in temperature. At higher temperatures, some of the water molecules in the hydration shells or those near the surface start participating in the diffusion process and at 293 K, almost all water molecules contribute to the dynamics. Diffusivity of water in both SAP-1 and SAP-2 are found to be lower in comparison to the bulk, and within the two samples of saponite clay diffusivity in SAP-1 is found to be lower compared to SAP-2; this has been explained on the basis of the charge on the tetrahedral layers and the charge balancing cations in the interlayer spacing.
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Affiliation(s)
- S Mitra
- Solid State Physics Division, Bhabha Atomic Research Centre, Mumbai 400085, India
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16
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Bertrand CE, Liu KH, Mamontov E, Chen SH. Hydration-dependent dynamics of deeply cooled water under strong confinement. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2013; 87:042312. [PMID: 23679419 DOI: 10.1103/physreve.87.042312] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2013] [Revised: 03/20/2013] [Indexed: 06/02/2023]
Abstract
We have measured the hydration-level dependence of the single-particle dynamics of water confined in the ordered mesoporous silica MCM-41. The dynamic crossover observed at full hydration is absent at monolayer hydration. The monolayer dynamics are significantly slower than those of water in a fully hydrated pore at ambient temperatures. At low temperatures, the opposite is found to be true. These results underscore the importance of water's tetrahedral hydrogen-bond network in accounting for its low temperature dynamic properties.
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Affiliation(s)
- C E Bertrand
- Department of Nuclear Science & Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
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18
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Bertrand CE, Zhang Y, Chen SH. Deeply-cooled water under strong confinement: neutron scattering investigations and the liquid–liquid critical point hypothesis. Phys Chem Chem Phys 2013. [DOI: 10.1039/c2cp43235h] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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19
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Busselez R, Arbe A, Cerveny S, Capponi S, Colmenero J, Frick B. Component dynamics in polyvinylpyrrolidone concentrated aqueous solutions. J Chem Phys 2012; 137:084902. [DOI: 10.1063/1.4746020] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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20
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Jiménez-Ruiz M, Ferrage E, Delville A, Michot LJ. Anisotropy on the collective dynamics of water confined in swelling clay minerals. J Phys Chem A 2012; 116:2379-87. [PMID: 22324768 DOI: 10.1021/jp201543t] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Collective excitations of water confined in the interlayer space of swelling clay minerals were studied by means of inelastic neutron scattering. The effect of bidimensional confinement on the dynamics of the interlayer water was investigated by using a synthetic Na-saponite sample with a general formula of Si(7.3)Al(0.7)Mg(6)O(20)(OH)(4)Na(0.7) in a bilayer hydration state. Experimental results reveal two inelastic signals, different from those described for bulk water with a clear anisotropy on the low-energy excitation of the collective dynamics of interlayer water, this difference being stronger in the perpendicular direction. Results obtained for the parallel direction follow the same trend as bulk water, and the effect of the confinement is mainly manifested from the fact that clay interlayer water is more structured than bulk water. Data obtained in the perpendicular direction display a nondispersive behavior below a cutoff wavenumber value, Q(c), indicating a nonpropagative excitation below that value. Molecular dynamics simulations results agree qualitatively with the experimental results.
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Affiliation(s)
- M Jiménez-Ruiz
- Institut Laue Langevin, 6 Rue Jules Horowitz, BP. 156, F-38042 Grenoble Cedex 9, France.
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21
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Mallamace F, Corsaro C, Baglioni P, Fratini E, Chen SH. The dynamical crossover phenomenon in bulk water, confined water and protein hydration water. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2012; 24:064103. [PMID: 22277288 DOI: 10.1088/0953-8984/24/6/064103] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
We discuss a phenomenon regarding water that was until recently a subject of scientific controversy, i.e. the dynamical crossover from fragile-to-strong glass-forming material, for both bulk and protein hydration water. Such a crossover is characterized by a temperature T(L) at which significant dynamical changes occur, such as violation of the Stokes-Einstein relation and changes of behaviour of homologous transport parameters such as the density relaxation time and the viscosity. In this respect we will consider carefully the dynamic properties of water-protein systems. More precisely, we will study proteins and their hydration water as far as bulk and confined water. In order to clarify the controversy we will discuss in a comparative way many previous and new experimental data that have emerged using different techniques and molecular dynamic simulation (MD). We point out the reasons for the different dynamical findings from the use of different experimental techniques.
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Affiliation(s)
- Francesco Mallamace
- Department of Nuclear Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
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22
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Pitman MC, van Duin ACT. Dynamics of Confined Reactive Water in Smectite Clay–Zeolite Composites. J Am Chem Soc 2012; 134:3042-53. [DOI: 10.1021/ja208894m] [Citation(s) in RCA: 121] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Affiliation(s)
- Michael C. Pitman
- Soft Matter Theory and Simulations
Group, Computational Biology Center, IBM Watson Research Center, Yorktown Heights, New York 10598, United States
| | - Adri C. T. van Duin
- Department of Mechanical and
Nuclear Engineering, Pennsylvania State University, 136 Research East Building, University Park, Pennsylvania 16802,
United States
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Yamada T, Yonamine R, Yamada T, Kitagawa H, Tyagi M, Nagao M, Yamamuro O. Quasi-Elastic Neutron Scattering Studies on Dynamics of Water Confined in Nanoporous Copper Rubeanate Hydrates. J Phys Chem B 2011; 115:13563-9. [DOI: 10.1021/jp2029467] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Takeshi Yamada
- Neutron Science Laboratory, Institute for Solid State Physics, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8581, Japan
- JST-CREST, 5 Sanban-cho, Chiyoda-ku, Tokyo 102-0075, Japan
| | - Ryo Yonamine
- Neutron Science Laboratory, Institute for Solid State Physics, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8581, Japan
| | - Teppei Yamada
- Graduate School of Science, Kyoto University, Kitashirakawa Oiwake-cho, Sakyo-ku, Kyoto 606-8502, Japan
- JST-CREST, 5 Sanban-cho, Chiyoda-ku, Tokyo 102-0075, Japan
| | - Hiroshi Kitagawa
- Graduate School of Science, Kyoto University, Kitashirakawa Oiwake-cho, Sakyo-ku, Kyoto 606-8502, Japan
- JST-CREST, 5 Sanban-cho, Chiyoda-ku, Tokyo 102-0075, Japan
| | - Madhusudan Tyagi
- NIST Center for Neutron Research, National Institute of Standards and Technology, 100 Bureau Drive, Gaithersburg, Maryland 20899-6102, United States
- Department of Materials Science and Engineering, University of Maryland, College Park, Maryland, 20742-2115, United States
| | - Michihiro Nagao
- NIST Center for Neutron Research, National Institute of Standards and Technology, 100 Bureau Drive, Gaithersburg, Maryland 20899-6102, United States
- Center for Exploration of Energy and Matter, Indiana University, Bloomington, Indiana 47408-1398, United States
| | - Osamu Yamamuro
- Neutron Science Laboratory, Institute for Solid State Physics, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8581, Japan
- JST-CREST, 5 Sanban-cho, Chiyoda-ku, Tokyo 102-0075, Japan
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25
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Marry V, Dubois E, Malikova N, Durand-Vidal S, Longeville S, Breu J. Water dynamics in hectorite clays: influence of temperature studied by coupling neutron spin echo and molecular dynamics. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2011; 45:2850-2855. [PMID: 21381672 DOI: 10.1021/es1031932] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Within the wider context of water behavior in soils, and with a particular emphasis on clays surrounding underground radioactive waste packages, we present here the translational dynamics of water in clays in low hydrated states as studied by coupling molecular dynamics (MD) simulations and quasielastic neutron scattering experiments by neutron spin echo (NSE). A natural montmorillonite clay of interest is modeled by a synthetic clay which allows us to understand the determining parameters from MD simulations by comparison with the experimental values. We focus on temperatures between 300 and 350 K, i.e., the range relevant to the highlighted application. The activation energy Ea experimentally determined is 6.6 kJ/mol higher than that for bulk water. Simulations are in good agreement with experiments for the relevant set of conditions, and they give more insight into the origin of the observed dynamics.
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Affiliation(s)
- Virginie Marry
- UPMC University Paris 06, UMR 7195, PECSA, F-75005 Paris, France
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26
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Prisk TR, Tyagi M, Sokol PE. Dynamics of small-molecule glass formers confined in nanopores. J Chem Phys 2011; 134:114506. [DOI: 10.1063/1.3560039] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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27
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Sobolev O, Favre Buivin F, Kemner E, Russina M, Beuneu B, Cuello G, Charlet L. Water–clay surface interaction: A neutron scattering study. Chem Phys 2010. [DOI: 10.1016/j.chemphys.2010.06.012] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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28
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Bonnaud PA, Coasne B, Pellenq RJM. Molecular simulation of water confined in nanoporous silica. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2010; 22:284110. [PMID: 21399282 DOI: 10.1088/0953-8984/22/28/284110] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
This paper reports on a molecular simulation study of the thermodynamics, structure and dynamics of water confined at ambient temperature in hydroxylated silica nanopores of a width H = 10 and 20 Å. The adsorption isotherms for water in these nanopores resemble those observed for experimental samples; the adsorbed amount increases continuously in the multilayer adsorption regime until a jump occurs due to capillary condensation of the fluid within the pore. Strong layering of water in the vicinity of the silica surfaces is observed as marked density oscillations are observed up to 8 Å from the surface in the density profiles for confined water. Our results indicate that water molecules within the first adsorbed layer tend to adopt a H-down orientation with respect to the silica substrate. For all pore sizes and adsorbed amounts, the self-diffusivity of confined water is lower than the bulk, due to the hydrophilic interaction between the water molecules and the hydroxylated silica surface. Our results also suggest that the self-diffusivity of confined water is sensitive to the adsorbed amount.
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Affiliation(s)
- P A Bonnaud
- Centre Interdisciplinaire des Nanosciences de Marseille, CNRS and Aix-Marseille Université, Campus de Luminy, F-13288 Marseille Cedex 9, France
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29
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Malikova N, Dubois E, Marry V, Rotenberg B, Turq P. Dynamics in Clays - Combining Neutron Scattering and Microscopic Simulation. ACTA ACUST UNITED AC 2010. [DOI: 10.1524/zpch.2010.6097] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Abstract
Mobility of ions and water in clays is at the heart of their remarkable properties of water retention and ion-exchange. It has been addressed here using two microscopic techniques: neutron scattering and molecular dynamics simulations. Neutron scattering gives access exclusively to water dynamics in clays, due to the exceptional sensitivity of neutrons to H atoms. The data interpretation can be challenging, especially for natural clays such as montmorillonite, with inhomogeneous swelling characteristics. A great improvement is achieved with the use of synthetic materials, as demonstrated here on the case of synthetic (fluoro)hectorite. The standard analytical models for long-range diffusive motion, isotropic translation and its derivative, powder averaged two dimensional translation, have been used to interpret the neutron scattering data. They both agree on the order of magnitude for the diffusion coefficient of water in monohydrated and bihydrated clays, 10−10 m2s−1 and 10−9 m2s−1 respectively. While the two-dimensional nature of water diffusion in clays is seen clearly from molecular dynamics simulations, its signature in neutron scattering data is obscured by the powder-averaging of the signal. A novel method, based on a multi-resolution analysis of scattering functions from powder samples, allows never-the-less a clear determination of the dimensionality of water motion in the system. Extracting information on local water motion is difficult on the basis of neutron scattering data only. Various models for localised motion, rotation on a sphere or jump diffusion, have been proposed and used to interpret the observed neutron data, however their applicability is questionable in light of information from molecular dynamics simulations. Aside from aiding the interpretation of neutron scattering data, MD simulations are most valuable in providing information on the behaviour of ions in clays. MD estimates the interlayer ion coefficients as of the some order of magnitude as water, even if the details of ionic motion are strikingly different between the two ions considered here, Na+ and Cs+. Further, MD has also allowed to address the topic of ion exchange between clay interlayers and bulk aqueous solution. The microscopic picture of water and ion motion in clays, emerging from neutron scattering and MD simulations, should be treated as a building block of the overall modelling of macroscopic transport in clays, the ultimate property of interest for many clay applications.
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30
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Arbe A, Genix AC, Arrese-Igor S, Colmenero J, Richter D. Dynamics in Poly(n-alkyl methacrylates): A Neutron Scattering, Calorimetric, and Dielectric Study. Macromolecules 2010. [DOI: 10.1021/ma902833h] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Affiliation(s)
- A. Arbe
- Centro de Física de Materiales (CSIC−UPV/EHU), Apartado 1072, 20080 San Sebastián, Spain
| | - A.-C. Genix
- Laboratoire des Colloïdes, Verres et Nanomatériaux, UMR 5587 CNRS, Université Montpellier II, 34095 Montpellier, France
| | - S. Arrese-Igor
- Centro de Física de Materiales (CSIC−UPV/EHU), Apartado 1072, 20080 San Sebastián, Spain
| | - J. Colmenero
- Centro de Física de Materiales (CSIC−UPV/EHU), Apartado 1072, 20080 San Sebastián, Spain
- Departamento de Física de Materiales (UPV/EHU), Materials Physics Center (MPC), Apartado 1072, 20080 San Sebastián, Spain and Donostia International Physics Center, Paseo Manuel de Lardizabal 4, 20018 San Sebastián, Spain
| | - D. Richter
- Institut für Festkörperforschung, Forschungszentrum Jülich GmbH, D-52425 Jülich, Germany
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31
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Swenson J, Teixeira J. The glass transition and relaxation behavior of bulk water and a possible relation to confined water. J Chem Phys 2010; 132:014508. [DOI: 10.1063/1.3285286] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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32
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Bordallo HN, Aldridge LP, Fouquet P, Pardo LC, Unruh T, Wuttke J, Yokaichiya F. Hindered water motions in hardened cement pastes investigated over broad time and length scales. ACS APPLIED MATERIALS & INTERFACES 2009; 1:2154-2162. [PMID: 20355849 DOI: 10.1021/am900332n] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
We investigated the dynamics of confined water in different hydrated cement pastes with minimized contributions of capillary water. It was found that the water motions are extremely reduced compared to those of bulk water. The onset of water mobility, which was modified by the local environment, was investigated with elastic temperature scans using the high-resolution neutron backscattering instrument SPHERES. Using a Cauchy-Lorenz distribution, the quasi-elastic signal observed in the spectra obtained by the backscattering spectrometer was analyzed, leading to the identification of rotational motions with relaxation times of 0.3 ns. Additionally, neutron spin echo (NSE) spectroscopy was used to measure the water diffusion over the local network of pores. The motions observed in the NSE time scale were characterized by diffusion constants ranging from 0.6 to 1.1 x 10(-9) m(2) s(-1) most likely related to water molecules removed from the interface. In summary, our results indicate that the local diffusion observed in the gel pores of hardened cement pastes is on the order of that found in deeply supercooled water. Finally, the importance of the magnetic properties of cement pastes were discussed in relation to the observation of a quasi-elastic signal on the dried sample spectra measured using the time-of-flight spectrometer.
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Affiliation(s)
- Heloisa N Bordallo
- Helmholtz-Zentrum Berlin fur Materialien und Energie GmbH, Glienicker Strasse 100, D-14109 Berlin, Germany.
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33
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Porion P, Delville A. Multinuclear NMR study of the structure and micro-dynamics of counterions and water molecules within clay colloids. Curr Opin Colloid Interface Sci 2009. [DOI: 10.1016/j.cocis.2008.08.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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34
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Jansson H, Kargl F, Fernandez-Alonso F, Swenson J. Dynamics of a protein and its surrounding environment: A quasielastic neutron scattering study of myoglobin in water and glycerol mixtures. J Chem Phys 2009; 130:205101. [DOI: 10.1063/1.3138765] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
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35
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Structure and Dynamics of Fluids in Microporous and Mesoporous Earth and Engineered Materials. NEUTRON APPLICATIONS IN EARTH, ENERGY AND ENVIRONMENTAL SCIENCES 2009. [DOI: 10.1007/978-0-387-09416-8_19] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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37
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Swenson J, Kargl F, Berntsen P, Svanberg C. Solvent and lipid dynamics of hydrated lipid bilayers by incoherent quasielastic neutron scattering. J Chem Phys 2008; 129:045101. [DOI: 10.1063/1.2955753] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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38
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Kamitakahara WA, Wada N. Neutron spectroscopy of water dynamics in NaX and NaA zeolites. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2008; 77:041503. [PMID: 18517624 DOI: 10.1103/physreve.77.041503] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2007] [Indexed: 05/24/2023]
Abstract
We have investigated the dynamics of water molecules in zeolites NaA and NaX by high-resolution quasielastic neutron scattering methods. Between 260 and 310 K, the local translational diffusive motion of water in the zeolites is one to two orders of magnitude slower than in bulk water. The Q dependence of the scattering shows effects of confinement and the presence of both relatively mobile and immobile molecules. The speed of the diffusive motion depends strongly on hydration level. Comparison with other hydrated siliceous materials indicates that the host charge per water molecule is a major factor in determining the time scale of diffusion.
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Affiliation(s)
- William A Kamitakahara
- NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, Maryland 20899-6102, USA
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39
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Marry V, Rotenberg B, Turq P. Structure and dynamics of water at a clay surface from molecular dynamics simulation. Phys Chem Chem Phys 2008; 10:4802-13. [DOI: 10.1039/b807288d] [Citation(s) in RCA: 175] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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40
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Colmenero J, Arbe A. Segmental dynamics in miscible polymer blends: recent results and open questions. SOFT MATTER 2007; 3:1474-1485. [PMID: 32900101 DOI: 10.1039/b710141d] [Citation(s) in RCA: 101] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
In this short review we summarize the outcome of the large amount of effort made during the past decade from both the experimental and the theoretical point of view in order to understand the effect of blending on the segmental dynamics in polymers. Each of the two families of models proposed-one based on thermally activated concentration fluctuations, the other on chain connectivity effects-account for each of the two main experimental observations: the broadening of the component response with respect to that of the homopolymer and the dynamic heterogeneity, respectively. The complementarity of these approaches, their main achievements and failures, are critically revised. We also include recent results on blends of components with very different mobilities. In the neighbourhood of the glass-transition of the slow polymer, the dynamics of the other component seem to be confined within the frozen chains. We suggest possible ingredients and new routes to be considered in order to elaborate more predictive theoretical frameworks for all these phenomena.
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Affiliation(s)
- J Colmenero
- Centro de Física de Materiales (CSIC-UPV/EHU), Apartado 1072, 20080, San Sebastián, Spain and Donostia International Physics Center, San Sebastián, Spain.
| | - A Arbe
- Centro de Física de Materiales (CSIC-UPV/EHU), Apartado 1072, 20080, San Sebastián, Spain
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Frunza L, Schönhals A, Frunza S, Parvulescu VI, Cojocaru B, Carriazo D, Martín C, Rives V. Rotational Fluctuations of Water Confined to Layered Oxide Materials: Nonmonotonous Temperature Dependence of Relaxation Times. J Phys Chem A 2007; 111:5166-75. [PMID: 17536791 DOI: 10.1021/jp0717140] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The rotational molecular dynamics of water confined to layered oxide materials with brucite structure was studied by dielectric spectroscopy in the frequency range from 10(-2) to 10(7) Hz and in a broad temperature interval. The layered double hydroxide samples show one relaxation process, which was assigned to fluctuations of water molecules forming a layer, strongly adsorbed to the oxide surface. The temperature dependence of the relaxation rates has an unusual saddlelike shape characterized by a maximum. The model of Ryabov et al. (J. Phys. Chem. B 2001, 105, 1845) recently applied to describe the dynamics of water molecules in porous glasses is employed also for the layered materials. This model assumes two competing effects: rotational fluctuations of water molecules that take place simultaneously with defect formation, allowing the creation of free volume necessary for reorientation. The activation energy of rotational fluctuations, the energy of defect formation, a pre-exponential factor, and the defect concentration are obtained as main parameters from a fit of this model to the data. The values of these parameters were compared with those found for water confined to nanoporous molecular sieves, porous glasses, or bulk ice. Several correlations were discussed in detail, such as the lower the value of the energy of defect formation, the higher the number of defects. The pre-exponential factor increases with increasing activation energy, as an expression of the compensation law, and indicates the cooperative nature of the motional process. The involvement of the surface OH groups and of the oxygen atoms of the interlayer anions in the formation of hydrogen bonds was further discussed. For the birnessite sample, the relaxation processes are probably overlaid by a dominating conductivity contribution, which is analyzed in its frequency and temperature dependence. It is found that the conductivity of birnessite obeys the characteristics of semiconducting disordered materials. Especially the Barton/Nakajima/Namikawa relationship is fulfilled. Analyzing the temperature dependence of the direct current (dc) conductivity sigma0 in detail gives some hint that sigma0(T) has also an unusual saddlelike form.
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Affiliation(s)
- Ligia Frunza
- National Institute of Materials Physics, R-077125 Magurele, Romania.
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Abstract
Molecular dynamics simulations are carried out to investigate the permeation of ions and water in a membrane consisting of single wall carbon nanotubes possessing no surface charges connecting two reservoirs. Our simulations reveal that there are changes in the first hydration shell of the ions upon confinement in tubes of 0.82 or 0.90 nm effective internal diameter. Although the first minimum in the g(r) is barely changed in the nanotube compared to in the bulk solution, the hydration number of Na(+) ion is reduced by 1.0 (from 4.5 in bulk to 3.5 in the 0.90 nm tube) and the hydration number is reduced further in the 0.82 nm tube. The changes in the hydration shell of Cl(-) ion are negligible, within statistical errors. The water molecules of the first hydration shell of both ions exchange less frequently inside the tube than in the bulk solution. We compare ion trajectories for ions in the same tube under identical reservoir conditions but with different numbers of ions in the tubes. This permits investigation of changes in structure and dynamics which arise from multiple ion occupancy in a carbon nanotube possessing no surface charges. We also investigated the effects of tube flexibility. Ions enter the tubes so as to form a train of ion pairs. We find that the radial distribution profiles of Na(+) ions broaden significantly systematically with increasing number of ion pairs in the tube. The radial distribution profiles of Cl(-) ions change only slightly with increasing number of ions in the tube. Trajectories reveal that Na(+) ions do not pass each other in 0.90 nm tubes, while Cl(-) ions pass each other, as do ions of opposite charge. An ion entering the tube causes the like-charged ions preceding it in the tube to be displaced along the tube axis and positive or negative ions will exit the tube only when one or two other ions of the same charge are present in the tube. Thus, the permeation mechanism involves multiple ions and Coulomb repulsion among the ions plays an essential role.
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Affiliation(s)
- Hongmei Liu
- Department of Chemical Engineering, University of Illinois at Chicago, Chicago, IL 60607, USA
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Swenson J, Jansson H, Bergman R. Relaxation processes in supercooled confined water and implications for protein dynamics. PHYSICAL REVIEW LETTERS 2006; 96:247802. [PMID: 16907281 DOI: 10.1103/physrevlett.96.247802] [Citation(s) in RCA: 111] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2006] [Indexed: 05/11/2023]
Abstract
We show that the viscosity-related main (alpha) relaxation of confined water vanishes at a temperature where the volume required for the cooperative alpha relaxation becomes larger than the size of the geometrically confined water cluster. This occurs typically around 200 K, implying that above this temperature we observe a merged alpha-beta relaxation, whereas below it only a local (beta) relaxation remains. This also means that such confined supercooled water does not exhibit any true glass transition, in contrast to other liquids in similar confinements. Furthermore, it implies that deeply supercooled water in biological systems, such as membranes and proteins, generally shows only a local beta relaxation, a finding of importance for low temperature properties of biological materials.
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Affiliation(s)
- Jan Swenson
- Department of Applied Physics, Chalmers University of Technology, SE-412 96 Göteborg, Sweden
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Tyagi M, Murthy SSN. Dynamics of water in supercooled aqueous solutions of glucose and poly(ethylene glycol)s as studied by dielectric spectroscopy. Carbohydr Res 2006; 341:650-62. [PMID: 16442507 DOI: 10.1016/j.carres.2006.01.006] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2005] [Revised: 12/09/2005] [Accepted: 12/28/2005] [Indexed: 11/23/2022]
Abstract
The dielectric behaviour of aqueous solutions of glucose, poly(ethylene glycol)s (PEGs) 200 and 600, and poly(vinyl pyrrolidone) (PVP) has been examined at different concentrations in the frequency range of 10(6)-10(-3) Hz by dielectric spectroscopy and by using differential scanning calorimetry down to 77 K from room temperature. The shape of the relaxation spectra and the temperature dependence of the relaxation rates have been critically examined along with temperature dependence of dielectric strength. In addition to the so-called primary (alpha-) relaxation process, which is responsible for the glass-transition event at T(g), another relaxation process of comparable magnitude has been found to bifurcate from the main relaxation process on the water-rich side, which continues to the sub-T(g) region, exhibiting relaxation at low frequencies. The sub-T(g) process dominates the dielectric measurements in aqueous solutions of higher PEGs, and the main relaxation process is seen as a weak process. The sub-T(g) process was not observed when water was replaced by methanol in the binary mixtures. These observations suggest that the sub-T(g) process in the aqueous mixtures is due to the reorientational motion of the 'confined' water molecules. The corresponding dielectric strength shows a noticeable change at T(g), indicating a hindered rotation of water molecules in the glassy phase. The nature of this confined water appears to be anomalous compared to most other supercooled confined liquids.
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Affiliation(s)
- Madhusudan Tyagi
- School of Physical Sciences, Jawaharlal Nehru University, New Delhi 110 067, India
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Sanz J, Herrero CP, Serratosa JM. Arrangement and Mobility of Water in Vermiculite Hydrates Followed by 1H NMR Spectroscopy. J Phys Chem B 2006; 110:7813-9. [PMID: 16610877 DOI: 10.1021/jp0600561] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The arrangement of water molecules in one- and two-layer hydrates of high-charged vermiculites, saturated with alkaline (Li(+), Na(+)) and alkali-earth (Mg(2+), Ca(2+), Ba(2+)) cations, has been analyzed with (1)H NMR spectroscopy. Two different orientations for water molecules have been found, depending on the hydration state and the sites occupied by interlayer cations. As the amount of water increases, hydrogen bond interactions between water molecules increase at expenses of water-silicate interactions. This interaction favors water mobility in vermiculites. A comparison of the temperature dependence of relaxation times T(1) and T(2) for one and two-layer hydrates of Na-vermiculite shows that the rotations of water molecules around C(2)-axes and that of cation hydration shells around the c-axis is favored in the two-layer hydrate. In both hydrates, the anisotropic diffusion of water takes place at room temperature, preserving the orientation of water molecules relative to the silicate layers. Information obtained by NMR spectroscopy is compatible with that deduced by infrared spectroscopy and with structural studies carried out with X-ray and neutron diffraction techniques on single-crystals of vermiculite.
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Affiliation(s)
- J Sanz
- Instituto de Ciencia de Materiales, C.S.I.C., Cantoblanco, 28049 Madrid, Spain
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Malikova N, Cadène A, Marry V, Dubois E, Turq P. Diffusion of Water in Clays on the Microscopic Scale: Modeling and Experiment. J Phys Chem B 2006; 110:3206-14. [PMID: 16494330 DOI: 10.1021/jp056954z] [Citation(s) in RCA: 113] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Diffusion of water in montmorillonite clays at low hydration has been studied on the microscopic scale by two quasi-elastic neutron scattering techniques, neutron spin-echo (NSE) and time-of-flight (TOF), and by classical microscopic simulation. Experiment and simulation are compared both directly on the level of intermediate scattering functions, I(Q, t), and indirectly on the level of relaxation times after a model of atomic motion is applied. Regarding the dynamics of water in Na- and Cs-monohydrated montmorillonite samples, the simulation and NSE results show a very good agreement, both indicating diffusion coefficients of the order of (1-3) x 10(-10) m(2) s(-1). The TOF technique significantly underestimates water relaxation times (therefore overestimates water dynamics), by a factor of up to 3 and 7 in the two systems, respectively, primarily due to insufficiently long correlation times being probed. In the case of the Na-bihydrated system, the TOF results are in closer agreement with the other two techniques (the techniques differ by a factor of 2-3 at most), giving diffusion coefficients of (5-10) x 10(-10) m(2) s(-1). Attention has been also paid to the elastic incoherent structure factor, EISF(Q). Simulation has played a key role in understanding the various contributions to EISF(Q) in clay systems and in clearly distinguishing the signatures of "apparent" and true confinement. Indirectly, simulation highlights the difficulty in interpreting the EISF(Q) signal from powder clay samples used in experiments.
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Affiliation(s)
- N Malikova
- Laboratoire Liquides Ioniques et Interfaces Chargées, boite postale 51, Université P. et M. Curie, 4 place Jussieu, F-75252 Paris Cedex 05, France.
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Mamontov E. Observation of fragile-to-strong liquid transition in surface water in CeO2. J Chem Phys 2005; 123:171101. [PMID: 16375510 DOI: 10.1063/1.2125729] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
A quasielastic neutron-scattering experiment carried out on a backscattering spectrometer with sub-micro eV resolution in the temperature range of 200-250 K has revealed the dynamics of surface water in cerium oxide on the time scale of hundreds of picoseconds. This slow dynamics is attributed to the translational mobility of the water molecules in contact with the surface hydroxyl groups. The relaxation function of this slow motion can be described by a slightly stretched exponential with the stretch factor exceeding 0.9, which indicates almost a Debye-type dynamics. Down to about 220 K, the temperature dependence of the residence time for water molecules follows a Vogel-Fulcher-Tamman law with the glass transition temperature of 181 K. At lower temperatures, the residence time behavior abruptly changes, indicating a fragile-to-strong liquid transition in surface water at about 215 K.
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Affiliation(s)
- E Mamontov
- NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, Maryland 20899-8562, USA.
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Malikova N, Cadéne A, Marry V, Dubois E, Turq P, Zanotti JM, Longeville S. Diffusion of water in clays – microscopic simulation and neutron scattering. Chem Phys 2005. [DOI: 10.1016/j.chemphys.2005.04.035] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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50
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Mamontov E. High-resolution neutron-scattering study of slow dynamics of surface water molecules in zirconium oxide. J Chem Phys 2005; 123:24706. [PMID: 16050765 DOI: 10.1063/1.1949171] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We have performed a quasielastic neutron-scattering experiment on backscattering spectrometer with sub-mueV resolution to investigate the slow dynamics of surface water in zirconium oxide using the sample studied previously with a time-of-flight neutron spectrometer [E. Mamontov, J. Chem. Phys. 121, 9087 (2004)]. The backscattering measurements in the temperature range of 240-300 K have revealed a translational dynamics slower by another order of magnitude compared to the translational dynamics of the outer hydration layer observed in the time-of-flight experiment. The relaxation function of this slow motion is described by a stretched exponential with the stretch factors between 0.8 and 0.9, indicating a distribution of the relaxation times. The temperature dependence of the average residence time is non-Arrhenius, suggesting that the translational motion studied in this work is more complex than surface jump diffusion previously observed for the molecules of the outer hydration layer. The observed slow dynamics is ascribed to the molecules of the inner hydration layer that form more hydrogen bonds compared to the molecules of the outer hydration layer. Despite being slower by two orders of magnitude, the translational motion of the molecules of the inner hydration layer may have more in common with bulk water compared to the outer hydration layer, the dynamics of which is slower than that of bulk water by just one order of magnitude.
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Affiliation(s)
- E Mamontov
- National Institute of Standards and Technology (NIST) Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, Maryland 20899-8562, USA.
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