1
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Privalov AF, Sinitsyn VV, Vogel M. Transport Mechanism in Nafion Revealed by Detailed Comparison of 1H and 17O Nuclear Magnetic Resonance Diffusion Coefficients. J Phys Chem Lett 2023; 14:9335-9340. [PMID: 37819873 DOI: 10.1021/acs.jpclett.3c02229] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/13/2023]
Abstract
We use 1H and 17O NMR static field gradient diffusometry to measure self-diffusion coefficients of protons (DH) and oxygens (DO) in Nafion 212 with various hydration levels (λ = 4-18). For all samples and both nuclei, we obtain activation energies (Ea) of ≈0.19 eV. Analyzing the hydration-level dependence of DH and DO, we find DO/DH ≈ 1 at λ ≈ 18, resembling the situation in bulk water, while oxygen diffusion becomes faster than proton diffusion when the water content is decreased, leading to DO/DH ≈ 1.2 at λ ≈ 4. A comparison with literature data for acidic bulk solutions implies that faster oxygen than proton diffusion results from the existence of the polymer framework. To rationalize the observed ratios DO/DH ≥ 1, we consider a bimodal dynamical model in which the interactions of H+(H2O)m ions with neighboring SO3- groups lead to slower water dynamics in the vicinity of the polymer framework than in the center of the water nanochannels.
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Affiliation(s)
- Alexei F Privalov
- Institute for Condensed Matter Physics, Technische Universität Darmstadt, Hochschulstrasse 6, 64289 Darmstadt, Germany
| | - Vitaly V Sinitsyn
- National Research University High School of Economics, Myasnitskaya 20, 101000 Moscow, Russia
| | - Michael Vogel
- Institute for Condensed Matter Physics, Technische Universität Darmstadt, Hochschulstrasse 6, 64289 Darmstadt, Germany
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2
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Dupertuis N, Tarun OB, Lütgebaucks C, Roke S. Three-Dimensional Confinement of Water: H 2O Exhibits Long-Range (>50 nm) Structure while D 2O Does Not. NANO LETTERS 2022; 22:7394-7400. [PMID: 36067223 DOI: 10.1021/acs.nanolett.2c02206] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Water is the liquid of life thanks to its three-dimensional adaptive hydrogen (H)-bond network. Confinement of this network may lead to dramatic structural changes influencing chemical and physical transformations. Although confinement effects occur on a <1 nm length scale, the upper length scale limit is unknown. Here, we investigate 3D-confinement over lengths scales ranging from 58-140 nm. By confining water in zwitterionic liposomes of different sizes and measuring the change in H-bond network conformation using second harmonic scattering (SHS), we determined long-range confinement effects in light and heavy water. D2O displays no detectable 3D-confinement effects <58 nm (<3 × 106 D2O molecules). H2O is distinctly different. The vesicle enclosed inner H-bond network has a different conformation compared to the outside network and the SHS response scales with the volume of the confining space. H2O displays confinement effects over distances >100 nm (>2 × 107 H2O molecules).
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Affiliation(s)
- Nathan Dupertuis
- Laboratory for Fundamental BioPhotonics (LBP), Institute of Bioengineering (IBI), School of Engineering (STI), École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Orly B Tarun
- Laboratory for Fundamental BioPhotonics (LBP), Institute of Bioengineering (IBI), School of Engineering (STI), École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Cornelis Lütgebaucks
- Laboratory for Fundamental BioPhotonics (LBP), Institute of Bioengineering (IBI), School of Engineering (STI), École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Sylvie Roke
- Laboratory for Fundamental BioPhotonics (LBP), Institute of Bioengineering (IBI), School of Engineering (STI), École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
- Institute of Materials Science and Engineering (IMX), School of Engineering (STI), École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
- Lausanne Centre for Ultrafast Science, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
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3
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Horstmann R, Hecht L, Kloth S, Vogel M. Structural and Dynamical Properties of Liquids in Confinements: A Review of Molecular Dynamics Simulation Studies. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2022; 38:6506-6522. [PMID: 35580166 DOI: 10.1021/acs.langmuir.2c00521] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Molecular dynamics (MD) simulations are a powerful tool for detailed studies of altered properties of liquids in confinement, in particular, of changed structures and dynamics. They allow, on one hand, for perfect control and systematic variation of the geometries and interactions inherent in confinement situations and, on the other hand, for type-selective and position-resolved analyses of a huge variety of structural and dynamical parameters. Here, we review MD simulation studies on various types of liquids and confinements. The main focus is confined aqueous systems, but also ionic liquids and polymer and silica melts are discussed. Results for confinements featuring different interactions, sizes, shapes, and rigidity will be presented. Special attention will be given to situations in which the confined liquid and the confining matrix consist of the same type of particles and, hence, disparate liquid-matrix interactions are absent. Findings for the magnitude and the range of wall effects on molecular positions and orientations and on molecular dynamics, including vibrational motion and structural relaxation, are reviewed. Moreover, their dependence on the parameters of the confinement and their relevance to theoretical approaches to the glass transition are addressed.
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Affiliation(s)
- Robin Horstmann
- Institute of Condensed Matter Physics, Technische Universität Darmstadt, Hochschulstr. 6, 64289 Darmstadt, Germany
| | - Lukas Hecht
- Institute of Condensed Matter Physics, Technische Universität Darmstadt, Hochschulstr. 6, 64289 Darmstadt, Germany
| | - Sebastian Kloth
- Institute of Condensed Matter Physics, Technische Universität Darmstadt, Hochschulstr. 6, 64289 Darmstadt, Germany
| | - Michael Vogel
- Institute of Condensed Matter Physics, Technische Universität Darmstadt, Hochschulstr. 6, 64289 Darmstadt, Germany
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4
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Köster R, Vogel M. Slow liquid dynamics near solid surfaces: Insights from site-resolved studies of ionic liquids in silica confinement. J Chem Phys 2022; 156:074501. [DOI: 10.1063/5.0079722] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
| | - Michael Vogel
- Institute of Condensed Matter Physics, TU Darmstadt, Germany
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5
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Haridasan N, Sathian SP. Rotational dynamics of proteins in nanochannels: role of solvent's local viscosity. NANOTECHNOLOGY 2021; 32:225102. [PMID: 33621966 DOI: 10.1088/1361-6528/abe906] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Accepted: 02/23/2021] [Indexed: 06/12/2023]
Abstract
Viscosity variation of solvent in local regions near a solid surface, be it a biological surface of a protein or an engineered surface of a nanoconfinement, is a direct consequence of intermolecular interactions between the solid body and the solvent. The current coarse-grained molecular dynamics study takes advantage of this phenomenon to investigate the anomaly in a solvated protein's rotational dynamics confined using a representative solid matrix. The concept of persistence time, the characteristic time of structural reordering in liquids, is used to compute the solvent's local viscosity. With an increase in the degree of confinement, the confining matrix significantly influences the solvent molecule's local viscosity present in the protein hydration layer through intermolecular interactions. This effect contributes to the enhanced drag force on protein motion, causing a reduction in the rotational diffusion coefficient. Simulation results suggest that the direct matrix-protein non-bonded interaction is responsible for the occasional jump and discontinuity in orientational motion when the protein is in very tight confinement.
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Affiliation(s)
- Navaneeth Haridasan
- Micro and Nanoscale Transport Lab, Applied Mechanics Department, Indian Institute of Technology Madras, Chennai, India
| | - Sarith P Sathian
- Micro and Nanoscale Transport Lab, Applied Mechanics Department, Indian Institute of Technology Madras, Chennai, India
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6
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Hecht L, Horstmann R, Liebchen B, Vogel M. MD simulations of charged binary mixtures reveal a generic relation between high- and low-temperature behavior. J Chem Phys 2021; 154:024501. [PMID: 33445919 DOI: 10.1063/5.0031417] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Experimental studies of the glassy slowdown in molecular liquids indicate that the high-temperature activation energy E∞ of glass-forming liquids is directly related to their glass transition temperature Tg. To further investigate such a possible relation between high- and low-temperature dynamics in glass-forming liquids, we analyze the glassy dynamics of binary mixtures using molecular dynamics simulations. We consider a binary mixture of charged Lennard-Jones particles and vary the partial charges of the particles and, thus, the high-temperature activation energy and the glass transition temperature of the system. Based on previous results, we introduce a phenomenological model describing relaxation times over the whole temperature regime from high temperatures to temperatures well inside the supercooled regime. By investigating the dynamics of both particle species on molecular and diffusive length scales along isochoric and isobaric pathways, we find a quadratic charge dependence of both E∞ and Tg, resulting in an approximately constant ratio of both quantities independent of the underlying observable, the thermodynamic ensemble, and the particle species, and this result is robust against the actual definition of Tg. This generic relation between the activation energy and the glass transition temperature indicates that high-temperature dynamics and the glassy slowdown are related phenomena, and the knowledge of E∞ may allow us to approximately predict Tg.
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Affiliation(s)
- L Hecht
- Institut für Physik Kondensierter Materie, Technische Universität Darmstadt, Hochschulstr. 8, 64289 Darmstadt, Germany
| | - R Horstmann
- Institut für Physik Kondensierter Materie, Technische Universität Darmstadt, Hochschulstr. 6, 64289 Darmstadt, Germany
| | - B Liebchen
- Institut für Physik Kondensierter Materie, Technische Universität Darmstadt, Hochschulstr. 8, 64289 Darmstadt, Germany
| | - M Vogel
- Institut für Physik Kondensierter Materie, Technische Universität Darmstadt, Hochschulstr. 6, 64289 Darmstadt, Germany
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7
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Li S, Schmidt B. Replica exchange MD simulations of two-dimensional water in graphene nanocapillaries: rhombic versus square structures, proton ordering, and phase transitions. Phys Chem Chem Phys 2019; 21:17640-17654. [PMID: 31364628 DOI: 10.1039/c9cp00849g] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The hydrogen bond patterns, proton ordering, and phase transitions of monolayer ice in two-dimensional hydrophobic confinement are fundamentally different from those found for bulk ice. To investigate the behavior of quasi-2D ice, we perform molecular dynamics simulations of water confined between fixed graphene plates at a distance of 0.65 nm. While experimental results are still limited and theoretical investigations are often based on a single, often empirically based force field model, this work presents a systematic study modeling the water-graphene interaction by effective Lennard-Jones potentials previously derived from high-level ab initio CCSD(T) calculations of water adsorbed on graphene [Phys. Chem. Chem. Phys., 2013, 15, 4995]. For the water-water interaction different water force fields, i.e. SPCE, TIP3P, TIP4P, TIP4P/ICE, and TIP5P, are used. The water occupancy of the graphene capillary at a pressure of 1000 MPa is determined to be between 13.5 and 13.9 water molecules per square nanometer, depending on the choice of the water force field. Based on these densities, we explore the structure and dynamics of quasi-2D water for temperatures ranging from 200 K to about 600 K for each of the five force fields. To ensure complete sampling of the configurational space and to overcome the barriers separating metastable structures, these simulations are based on the replica exchange molecular dynamics technique. We report different tetragonal hydrogen bond patterns, which are classified as nearly square or as rhombic. While many of these arrangements are essentially flat, in some cases puckered arrangements are found, too. Also the proton ordering of the quasi-2D water structures is considered, allowing us to identify them as ferroelectric, ferrielectric or antiferroelectric. For temperatures between 200 K and 400 K we find several second-order phase transitions from one ice structure to another, changing in many cases both the arrangements of the oxygen atoms and the proton ordering. For temperatures between 400 K and 600 K there are melting-like transitions from a monolayer of ice to a monolayer of liquid water. These first-order phase transitions have a latent heat between 3.4 and 4.0 kJ mol-1. Both the values of the transition temperatures and of the latent heats display considerable model dependence for the five different water models investigated here.
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Affiliation(s)
- Shujuan Li
- Institute for Mathematics, Freie Universität Berlin, Arnimallee 6, D-14195 Berlin, Germany.
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8
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Wohlfromm T, Vogel M. On the coupling of protein and water dynamics in confinement: Spatially resolved molecular dynamics simulation studies. J Chem Phys 2019; 150:245101. [DOI: 10.1063/1.5097777] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Affiliation(s)
- Timothy Wohlfromm
- Institut für Festkörperphysik, Technische Universität Darmstadt, 64289 Darmstadt, Germany
| | - Michael Vogel
- Institut für Festkörperphysik, Technische Universität Darmstadt, 64289 Darmstadt, Germany
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9
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Horstmann R, P Sanjon E, Drossel B, Vogel M. Effects of confinement on supercooled tetrahedral liquids. J Chem Phys 2019; 150:214704. [PMID: 31176331 DOI: 10.1063/1.5095198] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We use molecular dynamics simulations to ascertain the effects of geometrical restriction on glass-forming tetrahedral liquids. Striving for a broad approach, we study families of waterlike and silicalike liquids, for which we systematically scale the partial charges and, hence, the relevance of the tetrahedral networks. The confined liquids and the confining matrices consist of the same type of particles to avoid disruptive interactions and distorted structures at the interfaces. Spatially resolved analyses show that these neutral confinements still impose static mobility gradients and density correlations on the liquids. We quantify the increasing degree and range of the altered properties upon cooling. For both families of models, common relations describe the confinement effects of all systems with tetrahedral order, while deviations occur for systems with lower polarities and different structures. The observations are rationalized by considering the fact that a pinned wall imprints a static energy landscape to a neighboring liquid. We explore the properties of this landscape based on changes in vibrational motion and structural relaxation and find that typical barrier heights amount to two to three times the activation energy of bulk dynamics. Combining the present and previous results, we predict the evolution of confinement effects down to the glass transition temperature for liquids without fragile-to-strong crossover. In addition, it is found for silicalike liquids that the temperature dependence of dynamic and static correlation lengths from confinement studies is not affected when cooling through fragile-to-strong transitions of the bulk materials, casting doubt on the relevance of these length scales for the glassy slowdown.
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Affiliation(s)
- R Horstmann
- Institut für Festkörperphysik, Technische Universität Darmstadt, Hochschulstr. 6, 64289 Darmstadt, Germany
| | - E P Sanjon
- Institut für Festkörperphysik, Technische Universität Darmstadt, Hochschulstr. 6, 64289 Darmstadt, Germany
| | - B Drossel
- Institut für Festkörperphysik, Technische Universität Darmstadt, Hochschulstr. 6, 64289 Darmstadt, Germany
| | - M Vogel
- Institut für Festkörperphysik, Technische Universität Darmstadt, Hochschulstr. 6, 64289 Darmstadt, Germany
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10
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Weigler M, Brodrecht M, Buntkowsky G, Vogel M. Reorientation of Deeply Cooled Water in Mesoporous Silica: NMR Studies of the Pore-Size Dependence. J Phys Chem B 2019; 123:2123-2134. [DOI: 10.1021/acs.jpcb.8b12204] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- M. Weigler
- Institut für Festkörperphysik, Technische Universität Darmstadt, Hochschulstr. 6, 64289 Darmstadt, Germany
| | - M. Brodrecht
- Eduard-Zintl-Institut für Anorganische und Physikalische Chemie, Technische Universität Darmstadt, Alarich-Weiss-Str. 8, 64287 Darmstadt, Germany
| | - G. Buntkowsky
- Eduard-Zintl-Institut für Anorganische und Physikalische Chemie, Technische Universität Darmstadt, Alarich-Weiss-Str. 8, 64287 Darmstadt, Germany
| | - M. Vogel
- Institut für Festkörperphysik, Technische Universität Darmstadt, Hochschulstr. 6, 64289 Darmstadt, Germany
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11
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Soprunyuk V, Schranz W. DMA study of water's glass transition in nanoscale confinement. SOFT MATTER 2018; 14:7246-7254. [PMID: 30137096 DOI: 10.1039/c8sm00133b] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Dynamic mechanical analysis (DMA) measurements of water confined in nanoporous silica have been performed as a function of temperature and frequency for different pore sizes (2.5-10 nm) at heating and cooling. Most of the data show three processes, P1, P2 and P3, where P1 and P2 depend on measurement frequency and P3 does not. The characteristic shift of P3 with pore size shows that this process corresponds to freezing/melting of "internal water", i.e. in the core of the pores. Thermal expansion data indicate - in agreement with e.g. [A. Taschin, P. Bartolini and R. Torre, Meas. Sci. Technol., 2017, 28, 014009] - that in all our nanoporous systems about 2 layers of water remain liquid much below the freezing point. Dynamic elastic measurements show clear signatures of glass freezing of this supercooled water in the vicinity of P1. Extrapolating the DMA data to the timescale (103 s) of adiabatic calorimetry unveils a systematic behaviour: P1(T) shows a clear size dependence for a broad range of pore diameters, i.e. 2.5 nm ≤ d ≤ 52 nm, implying (together with the corresponding activation energy 0.5 eV) that P1 corresponds to the glass-liquid transition of a few layers of supercooled water at Tg(d). An extrapolation of Tg(d) to d → ∞ yields Tg(∞) ≈ 136 K, the traditional value for bulk water. The small (liquid like) value of Young's modulus in a temperature region above P1 is most naturally explained assuming that the supercooled water in this range is still liquid, implying that Tg values of 160 K or even 210 K - as suggested by various authors - are unlikely.
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Affiliation(s)
- V Soprunyuk
- University of Vienna, Faculty of Physics, Physics of Functional Materials, Boltzmanngasse 5, A-1090 Wien, Austria.
| | - W Schranz
- University of Vienna, Faculty of Physics, Physics of Functional Materials, Boltzmanngasse 5, A-1090 Wien, Austria.
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12
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Geske J, Harrach M, Heckmann L, Horstmann R, Klameth F, Müller N, Pafong E, Wohlfromm T, Drossel B, Vogel M. Molecular Dynamics Simulations of Water, Silica, and Aqueous Mixtures in Bulk and Confinement. ACTA ACUST UNITED AC 2018. [DOI: 10.1515/zpch-2017-1042] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Abstract
Aqueous systems are omnipresent in nature and technology. They show complex behaviors, which often originate in the existence of hydrogen-bond networks. Prominent examples are the anomalies of water and the non-ideal behaviors of aqueous solutions. The phenomenology becomes even richer when aqueous liquids are subject to confinement. To this day, many properties of water and its mixtures, in particular, under confinement, are not understood. In recent years, molecular dynamics simulations developed into a powerful tool to improve our knowledge in this field. Here, our simulation results for water and aqueous mixtures in the bulk and in various confinements are reviewed and some new simulation data are added to improve our knowledge about the role of interfaces. Moreover, findings for water are compared with results for silica, exploiting that both systems form tetrahedral networks.
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Affiliation(s)
- Julian Geske
- Institut für Festkörperphysik , Technische Universität Darmstadt, Hochschulstr. 6 , 64289 Darmstadt , Germany
| | - Michael Harrach
- Institut für Festkörperphysik , Technische Universität Darmstadt, Hochschulstr. 6 , 64289 Darmstadt , Germany
| | - Lotta Heckmann
- Institut für Festkörperphysik , Technische Universität Darmstadt, Hochschulstr. 6 , 64289 Darmstadt , Germany
| | - Robin Horstmann
- Institut für Festkörperphysik , Technische Universität Darmstadt, Hochschulstr. 6 , 64289 Darmstadt , Germany
| | - Felix Klameth
- Institut für Festkörperphysik , Technische Universität Darmstadt, Hochschulstr. 6 , 64289 Darmstadt , Germany
| | - Niels Müller
- Institut für Festkörperphysik , Technische Universität Darmstadt, Hochschulstr. 6 , 64289 Darmstadt , Germany
| | - Elvira Pafong
- Institut für Festkörperphysik , Technische Universität Darmstadt, Hochschulstr. 6 , 64289 Darmstadt , Germany
| | - Timothy Wohlfromm
- Institut für Festkörperphysik , Technische Universität Darmstadt, Hochschulstr. 6 , 64289 Darmstadt , Germany
| | - Barbara Drossel
- Institut für Festkörperphysik , Technische Universität Darmstadt, Hochschulstr. 6 , 64289 Darmstadt , Germany
| | - Michael Vogel
- Institut für Festkörperphysik , Technische Universität Darmstadt, Hochschulstr. 6 , 64289 Darmstadt , Germany
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13
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Abstract
Abstract
Effects of interfaces on hydrogen-bonded liquids play major roles in nature and technology. Despite their importance, a fundamental understanding of these effects is still lacking. In large parts, this shortcoming is due to the high complexity of these systems, leading to an interference of various interactions and effects. Therefore, it is advisable to take gradual approaches, which start from well designed and defined model systems and systematically increase the level of intricacy towards more complex mimetics. Moreover, it is necessary to combine insights from a multitude of methods, in particular, to link novel preparation strategies and comprehensive experimental characterization with inventive computational and theoretical modeling. Such concerted approach was taken by a group of preparative, experimentally, and theoretically working scientists in the framework of Research Unit FOR 1583 funded by the Deutsche Forschungsgemeinschaft (German Research Foundation). This special issue summarizes the outcome of this collaborative research. In this introductory article, we give an overview of the covered topics and the main results of the whole consortium. The following contributions are review articles or original works of individual research projects.
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Affiliation(s)
- Gerd Buntkowsky
- Institut für Physikalische Chemie , Technische Universität Darmstadt , 64287 Darmstadt , Germany
| | - Michael Vogel
- Institut für Festkörperphysik , Technische Universität Darmstadt , 64295 Darmstadt , Germany
| | - Roland Winter
- Fakultät für Chemie und Chemische Biologie , Technische Universität Dortmund , 44227 Dortmund , Germany
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14
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Demuth D, Sattig M, Steinrücken E, Weigler M, Vogel M. 2H NMR Studies on the Dynamics of Pure and Mixed Hydrogen-Bonded Liquids in Confinement. Z PHYS CHEM 2018. [DOI: 10.1515/zpch-2017-1027] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
2H NMR is used to ascertain dynamical behaviors of pure and mixed hydrogen-bonded liquids in bulk and in confinement. Detailed comparisons of previous and new results in broad dynamic and temperature ranges reveal that confinement effects differ for various liquids and confinements. For water, molecular reorientation strongly depends on the confinement size, with much slower and less fragile structural relaxation under more severe geometrical restriction. Moreover, a dynamical crossover occurs when a fraction of solid water forms so that the dynamics of the fraction of liquid water becomes even more restricted and, as a consequence, changes from bulk-like to interface-dominated. For glycerol, by contrast, confinement has weak effects on the reorientation dynamics. Mixed hydrogen-bonded liquids show even more complex dynamical behaviors. For aqueous solutions, the temperature dependence of the structural relaxation becomes discontinuous when the concentration changes due to a freezing of water fractions. This tendency for partial crystallization is enhanced rather than reduced by confinement, because different liquid-matrix interactions of the molecular species induce micro-phase segregation, which facilitates ice formation in water-rich regions. In addition, dynamical couplings at solvent-protein interfaces are discussed. It is shown that, on the one hand, solvent dynamics are substantially slowed down at protein surfaces and, on the other hand, protein dynamics significantly depend on the composition and, thus, the viscosity of the solvent. Furthermore, a protein dynamical transition occurs when the amplitude of water-coupled restricted backbone dynamics vanishes upon cooling.
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Affiliation(s)
- Dominik Demuth
- Institut für Festkörperphysik , Technische Universität Darmstadt , Hochschulstr. 6 , 64289 Darmstadt , Germany
| | - Matthias Sattig
- Institut für Festkörperphysik , Technische Universität Darmstadt , Hochschulstr. 6 , 64289 Darmstadt , Germany
| | - Elisa Steinrücken
- Institut für Festkörperphysik , Technische Universität Darmstadt , Hochschulstr. 6 , 64289 Darmstadt , Germany
| | - Max Weigler
- Institut für Festkörperphysik , Technische Universität Darmstadt , Hochschulstr. 6 , 64289 Darmstadt , Germany
| | - Michael Vogel
- Institut für Festkörperphysik , Technische Universität Darmstadt , Hochschulstr. 6 , 64289 Darmstadt , Germany
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15
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Wang X, Tong X, Zhang H, Douglas JF. String-like collective motion and diffusion in the interfacial region of ice. J Chem Phys 2017; 147:194508. [DOI: 10.1063/1.5004177] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Xinyi Wang
- Department of Chemical and Materials Engineering, University of Alberta, Edmonton, Alberta T6G 1H9, Canada
| | - Xuhang Tong
- Department of Chemical and Materials Engineering, University of Alberta, Edmonton, Alberta T6G 1H9, Canada
| | - Hao Zhang
- Department of Chemical and Materials Engineering, University of Alberta, Edmonton, Alberta T6G 1H9, Canada
| | - Jack F. Douglas
- Materials Science and Engineering Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA
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16
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Sebastiani D. Ab-Initio Molecular Dynamics Simulations and Calculations of Spectroscopic Parameters in Hydrogen-Bonding Liquids in Confinement (Project 8). Z PHYS CHEM 2017. [DOI: 10.1515/zpch-2017-1006] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Abstract
We investigate the effect of several nanoscale confinements on structural and dynamical properties of liquid water and binary aqueous mixtures. By means of molecular dynamics simulations based on density functional theory and atomistic force fields. Our main focus is on the dependence on the structure and the hydrogen-bonding-network of the liquids near the confinement interface at atomistic resolution. As a complementary aspect, spatially resolved profiles of the proton NMR chemical shift values are used to quantify the local strength of the hydrogen-bond-network.
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Affiliation(s)
- Daniel Sebastiani
- Institute of Chemistry , Martin-Luther-Universität Halle-Wittenberg , von-Danckelmann-Platz 4 , 06120 Halle , Germany
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17
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Prado JR, Vyazovkin S. Phase separation of triethylamine and water in native and organically modified silica nanopores. J Chem Phys 2017; 147:114508. [PMID: 28938834 DOI: 10.1063/1.5003906] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
A mixture of triethylamine and water is a lower critical solution temperature system that demixes (separates into individual phases) on heating. Differential scanning calorimetry has been applied to study the process of demixing in native and organically modified silica nanopores whose size varied from 4 to 30 nm. It has been found that in both types of nanopores, the temperature and enthalpy of demixing decrease significantly with decreasing the pore size. Isoconversional kinetic analysis has been utilized to determine the activation energy and pre-exponential factor of the process. It has been demonstrated that the depression of the transition temperature upon nanoconfinement is associated with acceleration of the process due to lowering of the activation energy. Nanoconfinement has also been found to lower the pre-exponential factor of the process that has been linked to a decrease in the molecular mobility.
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Affiliation(s)
- J Rachel Prado
- Department of Chemistry, University of Alabama at Birmingham, 901 S. 14th Street, Birmingham, Alabama 35294, USA
| | - Sergey Vyazovkin
- Department of Chemistry, University of Alabama at Birmingham, 901 S. 14th Street, Birmingham, Alabama 35294, USA
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18
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Geske J, Drossel B, Vogel M. Structure and dynamics of a silica melt in neutral confinement. J Chem Phys 2017; 146:134502. [DOI: 10.1063/1.4979341] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Julian Geske
- Institut für Festkörperphysik, Technische Universität Darmstadt, Hochschulstraße 6, 64289 Darmstadt, Germany
| | - Barbara Drossel
- Institut für Festkörperphysik, Technische Universität Darmstadt, Hochschulstraße 6, 64289 Darmstadt, Germany
| | - Michael Vogel
- Institut für Festkörperphysik, Technische Universität Darmstadt, Hochschulstraße 6, 64289 Darmstadt, Germany
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19
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Schmitz R, Müller N, Ullmann S, Vogel M. A molecular dynamics simulations study on ethylene glycol-water mixtures in mesoporous silica. J Chem Phys 2016; 145:104703. [DOI: 10.1063/1.4962240] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Rebecca Schmitz
- Institut für Festkörperphysik, Technische Universität Darmstadt, 64289 Darmstadt, Germany
| | - Niels Müller
- Institut für Festkörperphysik, Technische Universität Darmstadt, 64289 Darmstadt, Germany
| | - Svenja Ullmann
- Institut für Festkörperphysik, Technische Universität Darmstadt, 64289 Darmstadt, Germany
| | - Michael Vogel
- Institut für Festkörperphysik, Technische Universität Darmstadt, 64289 Darmstadt, Germany
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20
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Zubeltzu J, Corsetti F, Fernández-Serra MV, Artacho E. Continuous melting through a hexatic phase in confined bilayer water. Phys Rev E 2016; 93:062137. [PMID: 27415238 DOI: 10.1103/physreve.93.062137] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2015] [Indexed: 04/19/2023]
Abstract
Liquid water is not only of obvious importance but also extremely intriguing, displaying many anomalies that still challenge our understanding of such an a priori simple system. The same is true when looking at nanoconfined water: The liquid between constituents in a cell is confined to such dimensions, and there is already evidence that such water can behave very differently from its bulk counterpart. A striking finding has been reported from computer simulations for two-dimensionally confined water: The liquid displays continuous or discontinuous melting depending on its density. In order to understand this behavior, we have analyzed the melting exhibited by a bilayer of nanoconfined water by means of molecular dynamics simulations. At high density we observe the continuous melting to be related to the phase change of the oxygens only, with the hydrogens remaining liquidlike throughout. Moreover, we find an intermediate hexatic phase for the oxygens between the liquid and a triangular solid ice phase, following the Kosterlitz-Thouless-Halperin-Nelson-Young theory for two-dimensional melting. The liquid itself tends to maintain the local structure of the triangular ice, with its two layers being strongly correlated yet with very slow exchange of matter. The decoupling in the behavior of the oxygens and hydrogens gives rise to a regime in which the complexity of water seems to disappear, resulting in what resembles a simple monoatomic liquid. This intrinsic tendency of our simulated water may be useful for understanding novel behaviors in other confined and interfacial water systems.
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Affiliation(s)
- Jon Zubeltzu
- CIC nanoGUNE, 20018 Donostia-San Sebastián, Spain
| | - Fabiano Corsetti
- CIC nanoGUNE, 20018 Donostia-San Sebastián, Spain
- Department of Materials and the Thomas Young Centre for Theory and Simulation of Materials, Imperial College London, London SW7 2AZ, United Kingdom
| | - M V Fernández-Serra
- Physics and Astronomy Department, SUNY Stony Brook University, New York 11794-3800, USA
| | - Emilio Artacho
- CIC nanoGUNE, 20018 Donostia-San Sebastián, Spain
- Theory of Condensed Matter, Cavendish Laboratory, University of Cambridge, Cambridge CB3 0HE, United Kingdom
- Basque Foundation for Science Ikerbasque, 48011 Bilbao, Spain
- Donostia International Physics Center, 20018 Donostia-San Sebastián, Spain
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21
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Henritzi P, Bormuth A, Klameth F, Vogel M. A molecular dynamics simulations study on the relations between dynamical heterogeneity, structural relaxation, and self-diffusion in viscous liquids. J Chem Phys 2016; 143:164502. [PMID: 26520522 DOI: 10.1063/1.4933208] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We perform molecular dynamics simulations for viscous liquids to study the relations between dynamical heterogeneity, structural (α) relaxation, and self-diffusion. For atomistic models of supercooled water, polymer melts, and an ionic liquid, we characterize the space-time characteristics of dynamical heterogeneity by the degree of deviations from Gaussian displacement statistics (α2), the size of clusters comprising highly mobile particles (S(w)), and the length of strings consisting of cooperatively moving particles (L(w)). Comparison of our findings with previous simulation results for a large variety of viscous liquids, ranging from monoatomic liquids to silica melt, reveals a nearly universal decoupling between the time scales of maximum non-Gaussian parameter (τ(α2)) and the time constant of the α relaxation (τ(α)) upon cooling, explicitly, τ(α2) ∝τ(α)(3/4). Such uniform relation was not observed between the peak times of S(w) or L(w) and τ(α). On the other hand, the temperature-dependent time scale of maximum string length (τ(L)) follows the inverse of the self-diffusion coefficient (D) for various systems at sufficiently low temperatures, i.e., τ(L) ∝ D(-1). These observations are discussed in view of a breakdown of the Stokes-Einstein relation for the studied systems. It is found that the degree of deviation from this relation is correlated with the stretching of the α relaxation.
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Affiliation(s)
- Patrick Henritzi
- Institut für Festkörperphysik, Technische Universität Darmstadt, 64289 Darmstadt, Germany
| | - André Bormuth
- Institut für Festkörperphysik, Technische Universität Darmstadt, 64289 Darmstadt, Germany
| | - Felix Klameth
- Institut für Festkörperphysik, Technische Universität Darmstadt, 64289 Darmstadt, Germany
| | - Michael Vogel
- Institut für Festkörperphysik, Technische Universität Darmstadt, 64289 Darmstadt, Germany
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22
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Cerveny S, Mallamace F, Swenson J, Vogel M, Xu L. Confined Water as Model of Supercooled Water. Chem Rev 2016; 116:7608-25. [PMID: 26940794 DOI: 10.1021/acs.chemrev.5b00609] [Citation(s) in RCA: 171] [Impact Index Per Article: 21.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Water in confined geometries has obvious relevance in biology, geology, and other areas where the material properties are strongly dependent on the amount and behavior of water in these types of materials. Another reason to restrict the size of water domains by different types of geometrical confinements has been the possibility to study the structural and dynamical behavior of water in the deeply supercooled regime (e.g., 150-230 K at ambient pressure), where bulk water immediately crystallizes to ice. In this paper we give a short review of studies with this particular goal. However, from these studies it is also clear that the interpretations of the experimental data are far from evident. Therefore, we present three main interpretations to explain the experimental data, and we discuss their advantages and disadvantages. Unfortunately, none of the proposed scenarios is able to predict all the observations for supercooled and glassy bulk water, indicating that either the structural and dynamical alterations of confined water are too severe to make predictions for bulk water or the differences in how the studied water has been prepared (applied cooling rate, resulting density of the water, etc.) are too large for direct and quantitative comparisons.
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Affiliation(s)
- Silvina Cerveny
- Centro de Física de Materiales (CFM CSIC/EHU) - Material Physics Centre (MPC) , Paseo Manuel de Lardizabal 5, 20018 San Sebastian, Spain.,Donostia International Physics Center , Paseo Manuel de Lardizabal 4, 20018 San Sebastián, Spain
| | - Francesco Mallamace
- Dipartimento di Fisica, Università di Messina , Vill. S. Agata, CP 55, I-98166 Messina, Italy
| | - Jan Swenson
- Department of Physics, Chalmers University of Technology , SE-412 96 Göteborg, Sweden
| | - Michael Vogel
- Institut für Festkörperphysik, Technische Universität Darmstadt , Hochschulstraße 6, 64289 Darmstadt, Germany
| | - Limei Xu
- International Centre for Quantum Materials and School of Physics, Peking University , , Beijing 100871, China.,Collaborative Innovation Center of Quantum Matter , Beijing 100871, China
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23
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Klameth F, Vogel M. Slow Water Dynamics near a Glass Transition or a Solid Interface: A Common Rationale. J Phys Chem Lett 2015; 6:4385-4389. [PMID: 26722975 DOI: 10.1021/acs.jpclett.5b02010] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Performing molecular dynamics simulations, we investigate the enormous slowdowns of water dynamics when approaching a glass transition or a solid interface. We show that both effects can be described on common grounds within a theoretical framework, which was recently proposed by Schweizer et al. and considers coupled local hopping and elastic distortion. For confined water, we correctly describe the variation of the α-relaxation time, τα, as a function of both temperature and position with respect to the interface. Exploiting our knowledge of a cooperative length scale ξ(T) from the confinement studies, we quantitatively rationalize the glassy slowdown, τα(T), and the Stokes-Einstein breakdown of bulk water. For both confined and bulk liquid, variations of the α-relaxation time are intimately related to changes of the cage-rattling amplitude.
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Affiliation(s)
- F Klameth
- Institut für Festkörperphysik, Technische Universität Darmstadt , Hochschulstr. 6, D-64289 Darmstadt, Germany
| | - M Vogel
- Institut für Festkörperphysik, Technische Universität Darmstadt , Hochschulstr. 6, D-64289 Darmstadt, Germany
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24
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Jahn M, Gekle S. Bulk and interfacial liquid water as a transient network. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2015; 92:052130. [PMID: 26651669 DOI: 10.1103/physreve.92.052130] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2015] [Indexed: 06/05/2023]
Abstract
The special macroscopic properties of liquid water stem from its structure as a complex network of molecules connected by hydrogen bonds. While the dynamics of single molecules within this network has been extensively investigated, only little attention has been paid to the closed loops (meshes) of hydrogen-bonded molecules which determine the network topology. Using molecular dynamics simulations we analyze the size, shape, geometrical arrangement, and dynamical stability of loops containing up to 10 hydrogen bonds. We find that six-membered loops in liquid water even at room temperature retain a striking similarity with the well-known structure of ice. Analyzing the network dynamics we find that rings of more than five hydrogen bonds are stabilized compared to a random collection containing the same number of single bonds. We finally show that in the vicinity of hydrophobic and hydrophilic interfaces loops arrange in a preferred orientation.
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Affiliation(s)
- Miriam Jahn
- Fachbereich Physik, Universität Bayreuth, Germany
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25
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Harrach MF, Drossel B. Structure and dynamics of TIP3P, TIP4P, and TIP5P water near smooth and atomistic walls of different hydroaffinity. J Chem Phys 2015; 140:174501. [PMID: 24811640 DOI: 10.1063/1.4872239] [Citation(s) in RCA: 174] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
We perform molecular dynamics simulations to observe the structure and dynamics of water using different water models (TIP3P, TIP4P, TIP5P) at ambient conditions, constrained by planar walls, which are either modeled by smooth potentials or regular atomic lattices, imitating the honeycomb-structure of graphene. We implement walls of different hydroaffinity, different lattice constant, and different types of interaction with the water molecules. We find that in the hydrophobic regime the smooth wall generally represents a good abstraction of the atomically rough walls, while in the hydrophilic regime there are noticeable differences in structure and dynamics between all stages of wall roughness. For a small lattice constant however the smooth and the atomically rough wall still share a number of structural and dynamical similarities. Out of the three water models, TIP5P water shows the largest degree of tetrahedral ordering and is often the one that is least perturbed by the presence of the wall.
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Affiliation(s)
- Michael F Harrach
- Institut für Festkörperphysik, Technische Universität Darmstadt, Hochschulstr. 6, 64289 Darmstadt, Germany
| | - Barbara Drossel
- Institut für Festkörperphysik, Technische Universität Darmstadt, Hochschulstr. 6, 64289 Darmstadt, Germany
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26
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Harrach MF, Klameth F, Drossel B, Vogel M. Effect of the hydroaffinity and topology of pore walls on the structure and dynamics of confined water. J Chem Phys 2015; 142:034703. [DOI: 10.1063/1.4905557] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Michael F. Harrach
- Institut für Festkörperphysik, Technische Universität Darmstadt, Hochschulstr. 6, 64289 Darmstadt, Germany
| | - Felix Klameth
- Institut für Festkörperphysik, Technische Universität Darmstadt, Hochschulstr. 6, 64289 Darmstadt, Germany
| | - Barbara Drossel
- Institut für Festkörperphysik, Technische Universität Darmstadt, Hochschulstr. 6, 64289 Darmstadt, Germany
| | - Michael Vogel
- Institut für Festkörperphysik, Technische Universität Darmstadt, Hochschulstr. 6, 64289 Darmstadt, Germany
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27
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28
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Allolio C, Klameth F, Vogel M, Sebastiani D. Ab Initio H2O in Realistic Hydrophilic Confinement. Chemphyschem 2014; 15:3955-62. [DOI: 10.1002/cphc.201402371] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2014] [Indexed: 12/19/2022]
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29
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Klameth F, Henritzi P, Vogel M. Static and dynamic length scales in supercooled liquids: Insights from molecular dynamics simulations of water and tri-propylene oxide. J Chem Phys 2014; 140:144501. [DOI: 10.1063/1.4870089] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
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30
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Angulo-Sherman A, Mercado-Uribe H. Water under inner pressure: a dielectric spectroscopy study. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2014; 89:022406. [PMID: 25353481 DOI: 10.1103/physreve.89.022406] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2013] [Indexed: 06/04/2023]
Abstract
Water is the most studied substance on Earth. However, it is not completely understood why its structural and dynamical properties give rise to some anomalous behaviors. Some of them emerge when experiments at low temperatures and/or high pressures are performed. Here we report dielectric measurements on cold water under macroscopically constrained conditions, i.e., water in a large container at constant volume that cannot freeze below the melting point. The inner pressure in these conditions shifts the α relaxation peak to similar frequencies as seen in ice Ih. At 267 K we observe a peculiar response possibly due to the Grotthuss mechanism. At 251 K (the triple point) ice III forms.
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31
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Sattig M, Reutter S, Fujara F, Werner M, Buntkowsky G, Vogel M. NMR studies on the temperature-dependent dynamics of confined water. Phys Chem Chem Phys 2014; 16:19229-40. [DOI: 10.1039/c4cp02057j] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
NMR studies of water in nanoscopic confinements of various sizes reveal two dynamical crossovers related to a partial solidification of internal molecules and a glass transition of interfacial molecules, respectively.
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Affiliation(s)
- Matthias Sattig
- Institut für Festkörperphysik
- Technische Universität Darmstadt
- 64289 Darmstadt, Germany
| | - Stefan Reutter
- Institut für Festkörperphysik
- Technische Universität Darmstadt
- 64289 Darmstadt, Germany
| | - Franz Fujara
- Institut für Festkörperphysik
- Technische Universität Darmstadt
- 64289 Darmstadt, Germany
| | - Mayke Werner
- Eduard-Zintl-Institut für Anorganische und Physikalische Chemie
- Technische Universität Darmstadt
- 64287 Darmstadt, Germany
| | - Gerd Buntkowsky
- Eduard-Zintl-Institut für Anorganische und Physikalische Chemie
- Technische Universität Darmstadt
- 64287 Darmstadt, Germany
| | - Michael Vogel
- Institut für Festkörperphysik
- Technische Universität Darmstadt
- 64289 Darmstadt, Germany
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