151
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Dinkgreve M, Paredes J, Michels MAJ, Bonn D. Universal rescaling of flow curves for yield-stress fluids close to jamming. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2015; 92:012305. [PMID: 26274160 DOI: 10.1103/physreve.92.012305] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2015] [Indexed: 06/04/2023]
Abstract
The experimental flow curves of four different yield-stress fluids with different interparticle interactions are studied near the jamming concentration. By appropriate scaling with the distance to jamming all rheology data can be collapsed onto master curves below and above jamming that meet in the shear-thinning regime and satisfy the Herschel-Bulkley and Cross equations, respectively. In spite of differing interactions in the different systems, master curves characterized by universal scaling exponents are found for the four systems. A two-state microscopic theory of heterogeneous dynamics is presented to rationalize the observed transition from Herschel-Bulkley to Cross behavior and to connect the rheological exponents to microscopic exponents for the divergence of the length and time scales of the heterogeneous dynamics. The experimental data and the microscopic theory are compared with much of the available literature data for yield-stress systems.
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Affiliation(s)
- M Dinkgreve
- Van der Waals-Zeeman Institute, Institute of Physics, University of Amsterdam, Science Park 904, 1018 XH Amsterdam, The Netherlands
| | - J Paredes
- Van der Waals-Zeeman Institute, Institute of Physics, University of Amsterdam, Science Park 904, 1018 XH Amsterdam, The Netherlands
| | - M A J Michels
- Theory of Polymers and Soft Matter, Department of Applied Physics, Eindhoven University of Technology, P. O. Box 513, 5600 MB Eindhoven, The Netherlands
| | - D Bonn
- Van der Waals-Zeeman Institute, Institute of Physics, University of Amsterdam, Science Park 904, 1018 XH Amsterdam, The Netherlands
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152
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Su YS, I L. Cooling the two-dimensional short spherocylinder liquid to the tetratic phase: Heterogeneous dynamics with one-way coupling between rotational and translational hopping. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2015; 92:012319. [PMID: 26274173 DOI: 10.1103/physreve.92.012319] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2015] [Indexed: 06/04/2023]
Abstract
We numerically demonstrate the transition from the isotropic liquid to the tetratic phase with quasilong-range tetratic alignment order (i.e., with nearly parallel or perpendicular aligned rods), for the cold two-dimensional (2D) short spherocylinder system before crystallization and investigate the thermal assisted heterogeneous rotational and translational micromotions. Comparing with the 2D liquid of isotropic particles, spherocylinders introduce extra rotational degrees of freedom and destroy packing isotropy and the equivalence between rotational and translational motions. It is found that cooling leads to the stronger dynamical heterogeneity with more cooperative hopping and the stronger retardations of rotational hopping than translational hopping. Under topological constraints from nearly parallel and perpendicular rods of the tetratic phase, longitudinal and transverse translational hopping can occur without rotational hopping, but not the reverse. The empty space trailing a neighboring translational hopping patch is needed for triggering the patch rotational hopping with its translational motion into the empty space. It is the origin for the observed increasing separation of hopping time scales and the one-way coupling between rotational and translational hopping. Strips of longitudinally or transversely aligned rods can be ruptured and reconnected with neighboring strips through buckling, kink formation, and patch rotation, under the unbalanced torques or forces from their neighboring rods and thermal kicks.
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Affiliation(s)
- Yen-Shuo Su
- Department of Physics and Center for Complex Systems, National Central University, Jhongli, Taiwan 32001, Republic of China
| | - Lin I
- Department of Physics and Center for Complex Systems, National Central University, Jhongli, Taiwan 32001, Republic of China
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153
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Kim J, Sung BJ. Dynamic decoupling and local atomic order of a model multicomponent metallic glass-former. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2015; 27:235102. [PMID: 25993620 DOI: 10.1088/0953-8984/27/23/235102] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The dynamics of multicomponent metallic alloys is spatially heterogeneous near glass transition. The diffusion coefficient of one component of the metallic alloys may also decouple from those of other components, i.e., the diffusion coefficient of each component depends differently on the viscosity of metallic alloys. In this work we investigate the dynamic heterogeneity and decoupling of a model system for multicomponent Pd43Cu27Ni10P20 melts by using a hard sphere model that considers the size disparity of alloys but does not take chemical effects into account. We also study how such dynamic behaviors would relate to the local atomic structure of metallic alloys. We find, from molecular dynamics simulations, that the smallest component P of multicomponent Pd43Cu27Ni10P20 melts becomes dynamically heterogeneous at a translational relaxation time scale and that the largest major component Pd forms a slow subsystem, which has been considered mainly responsible for the stabilization of amorphous state of alloys. The heterogeneous dynamics of P atoms accounts for the breakdown of Stokes-Einstein relation and also leads to the dynamic decoupling of P and Pd atoms. The dynamically heterogeneous P atoms decrease the lifetime of the local short-range atomic orders of both icosahedral and close-packed structures by orders of magnitude.
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Affiliation(s)
- Jeongmin Kim
- Department of Chemistry and Research Institute for Basic Science, Sogang University, Seoul 121-742, Republic of Korea
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154
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Assessing the role of static length scales behind glassy dynamics in polydisperse hard disks. Proc Natl Acad Sci U S A 2015; 112:6920-4. [PMID: 26038545 DOI: 10.1073/pnas.1501911112] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The possible role of growing static order in the dynamical slowing down toward the glass transition has recently attracted considerable attention. On the basis of random first-order transition theory, a new method to measure the static correlation length of amorphous order, called "point-to-set" (PTS) length, has been proposed and used to show that the dynamic length grows much faster than the static length. Here, we study the nature of the PTS length, using a polydisperse hard-disk system, which is a model that is known to exhibit a growing hexatic order upon densification. We show that the PTS correlation length is decoupled from the steeper increase of the correlation length of hexatic order and dynamic heterogeneity, while closely mirroring the decay length of two-body density correlations. Our results thus provide a clear example that other forms of order can play an important role in the slowing down of the dynamics, casting a serious doubt on the order-agnostic nature of the PTS length and its relevance to slow dynamics, provided that a polydisperse hard-disk system is a typical glass former.
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155
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Mondal C, Karmakar S, Sengupta S. Glass-Like Slow Dynamics in a Colloidal Solid with Multiple Ground States. J Phys Chem B 2015; 119:10902-10. [DOI: 10.1021/jp512952u] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Chandana Mondal
- Centre
for Advanced Materials, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700032, India
| | - Smarajit Karmakar
- TIFR Centre for Interdisciplinary Sciences, 21 Brundavan Colony, Narsingi, Hyderabad 500075, India
| | - Surajit Sengupta
- TIFR Centre for Interdisciplinary Sciences, 21 Brundavan Colony, Narsingi, Hyderabad 500075, India
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156
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Conrad H, Lehmkühler F, Fischer B, Westermeier F, Schroer MA, Chushkin Y, Gutt C, Sprung M, Grübel G. Correlated heterogeneous dynamics in glass-forming polymers. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2015; 91:042309. [PMID: 25974493 DOI: 10.1103/physreve.91.042309] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2015] [Indexed: 06/04/2023]
Abstract
We report x-ray photon correlation spectroscopy experiments on the dynamics of the glass-former polypropylene glycol covering a temperature range from room temperature to the glass transition at T(g)=205 K using silica tracer particles. Three temperature regimes are identified: At high temperatures, Brownian motion of the tracer particles is observed. Near T(g), the dynamics is hyperdiffusive and ballistic. Around 1.12T(g), we observe an intermediate regime. Here the stretching exponent of the Kohlrausch-Williams-Watts function becomes q dependent. By analyzing higher-order correlations in the scattering data, we find that dynamical heterogeneities dramatically increase in this intermediate-temperature regime. This leads to two effects: increasing heterogeneous dynamics and correlated motion at temperatures close to and below 1.12T(g).
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Affiliation(s)
- H Conrad
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany
| | - F Lehmkühler
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany
- The Hamburg Centre for Ultrafast Imaging, Luruper Chaussee 149, 22761 Hamburg, Germany
| | - B Fischer
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany
| | - F Westermeier
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany
| | - M A Schroer
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany
- The Hamburg Centre for Ultrafast Imaging, Luruper Chaussee 149, 22761 Hamburg, Germany
| | - Y Chushkin
- European Synchrotron Radiation Facility, Avenue des Martyrs 71, 38000 Grenoble, France
| | - C Gutt
- University of Siegen, Walter-Flex Straße 3, 57072 Siegen, Germany
| | - M Sprung
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany
| | - G Grübel
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany
- The Hamburg Centre for Ultrafast Imaging, Luruper Chaussee 149, 22761 Hamburg, Germany
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157
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Dunleavy AJ, Wiesner K, Yamamoto R, Royall CP. Mutual information reveals multiple structural relaxation mechanisms in a model glass former. Nat Commun 2015; 6:6089. [PMID: 25608791 PMCID: PMC4354007 DOI: 10.1038/ncomms7089] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2014] [Accepted: 12/11/2014] [Indexed: 12/03/2022] Open
Abstract
Among the key challenges to our understanding of solidification in the glass transition is that it is accompanied by little apparent change in structure. Recently, geometric motifs have been identified in glassy liquids, but a causal link between these motifs and solidification remains elusive. One 'smoking gun' for such a link would be identical scaling of structural and dynamic lengthscales on approaching the glass transition, but this is highly controversial. Here we introduce an information theoretic approach to determine correlations in displacement for particle relaxation encoded in the initial configuration of a glass-forming liquid. We uncover two populations of particles, one inclined to relax quickly, the other slowly. Each population is correlated with local density and geometric motifs. Our analysis further reveals a dynamic lengthscale similar to that associated with structural properties, which may resolve the discrepancy between structural and dynamic lengthscales.
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Affiliation(s)
- Andrew J. Dunleavy
- H.H. Wills Physics Laboratory, Tyndall Avenue, Bristol BS8 1TL, UK
- School of Chemistry, Cantock’s Close, University of Bristol, Bristol BS8 1TS, UK
- Bristol Centre for Complexity Sciences, Bristol BS8 1TW, UK
| | - Karoline Wiesner
- Bristol Centre for Complexity Sciences, Bristol BS8 1TW, UK
- School of Mathematics, University of Bristol, Bristol BS8 1TW, UK
| | - Ryoichi Yamamoto
- Department of Chemical Engineering, Kyoto University, Kyoto 615-8510, Japan
| | - C. Patrick Royall
- H.H. Wills Physics Laboratory, Tyndall Avenue, Bristol BS8 1TL, UK
- School of Chemistry, Cantock’s Close, University of Bristol, Bristol BS8 1TS, UK
- Centre for Nanoscience and Quantum Information, Tyndall Avenue, Bristol BS8 1FD, UK
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158
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Wu ZW, Li MZ, Wang WH, Liu KX. Hidden topological order and its correlation with glass-forming ability in metallic glasses. Nat Commun 2015; 6:6035. [DOI: 10.1038/ncomms7035] [Citation(s) in RCA: 89] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2014] [Accepted: 12/03/2014] [Indexed: 11/09/2022] Open
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159
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Castillo G, Mujica N, Soto R. Universality and criticality of a second-order granular solid-liquid-like phase transition. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2015; 91:012141. [PMID: 25679604 DOI: 10.1103/physreve.91.012141] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2014] [Indexed: 06/04/2023]
Abstract
We experimentally study the critical properties of the nonequilibrium solid-liquid-like transition that takes place in vibrated granular matter. The critical dynamics is characterized by the coupling of the density field with the bond-orientational order parameter Q(4), which measures the degree of local crystallization. Two setups are compared, which present the transition at different critical accelerations as a result of modifying the energy dissipation parameters. In both setups five independent critical exponents are measured, associated to different properties of Q(4): the correlation length, relaxation time, vanishing wavenumber limit (static susceptibility), the hydrodynamic regime of the pair correlation function, and the amplitude of the order parameter. The respective critical exponents agree in both setups and are given by ν(⊥)=1,ν(∥)=2,γ=1,η≈0.6-0.67, and β=1/2, whereas the dynamical critical exponent is z=ν(∥)/ν(⊥)=2. The agreement on five exponents is an exigent test for the universality of the transition. Thus, while dissipation is strictly necessary to form the crystal, the path the system undergoes toward the phase separation is part of a well-defined universality class. In fact, the local order shows critical properties while density does not. Being the later conserved, the appropriate model that couples both is model C in the Hohenberg and Halperin classification. The measured exponents are in accord with the nonequilibrium extension to model C if we assume that α, the exponent associated in equilibrium to the specific heat divergence but with no counterpart in this nonequilibrium experiment, vanishes.
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Affiliation(s)
- Gustavo Castillo
- Departamento de Física, Facultad de Ciencias Físicas y Matemáticas, Universidad de Chile, Avenida Blanco Encalada 2008, Santiago, Chile and Laboratoire de Physique Statistique, Ecole Normale Supérieure, UMR CNRS 8550, 24 Rue Lhomond, 75005 Paris, France
| | - Nicolás Mujica
- Departamento de Física, Facultad de Ciencias Físicas y Matemáticas, Universidad de Chile, Avenida Blanco Encalada 2008, Santiago, Chile
| | - Rodrigo Soto
- Departamento de Física, Facultad de Ciencias Físicas y Matemáticas, Universidad de Chile, Avenida Blanco Encalada 2008, Santiago, Chile
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160
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Xia C, Cao Y, Kou B, Li J, Wang Y, Xiao X, Fezzaa K. Angularly anisotropic correlation in granular packings. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2014; 90:062201. [PMID: 25615079 DOI: 10.1103/physreve.90.062201] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2012] [Indexed: 06/04/2023]
Abstract
We present an x-ray microtomography study of the three-dimensional structural correlations in monodisperse granular packings. By measuring an orientation-dependent pair correlation function, we find that the local structure shows an angularly anisotropic orientation correlation. The correlation is strongest along the major axis of the local Minkowski tensor of the Voronoi cell. It turns out that this anisotropic correlation is consistent with the existence of some locally favored structures. The study suggests the importance of high-order structural correlations in random granular packings.
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Affiliation(s)
- Chengjie Xia
- Department of Physics and Astronomy, Shanghai Jiao Tong University, 800 Dong Chuan Road, Shanghai 200240, China
| | - Yixin Cao
- Department of Physics and Astronomy, Shanghai Jiao Tong University, 800 Dong Chuan Road, Shanghai 200240, China
| | - Binquan Kou
- Department of Physics and Astronomy, Shanghai Jiao Tong University, 800 Dong Chuan Road, Shanghai 200240, China
| | - Jindong Li
- Department of Physics and Astronomy, Shanghai Jiao Tong University, 800 Dong Chuan Road, Shanghai 200240, China
| | - Yujie Wang
- Department of Physics and Astronomy, Shanghai Jiao Tong University, 800 Dong Chuan Road, Shanghai 200240, China
| | - Xianghui Xiao
- Advanced Photon Source, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, Illinois 60439, USA
| | - Kamel Fezzaa
- Advanced Photon Source, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, Illinois 60439, USA
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161
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Descamps M, Decroix A. Polymorphism and disorder in caffeine: Dielectric investigation of molecular mobilities. J Mol Struct 2014. [DOI: 10.1016/j.molstruc.2014.04.042] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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162
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Kob W, Coslovich D. Nonlinear dynamic response of glass-forming liquids to random pinning. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2014; 90:052305. [PMID: 25493794 DOI: 10.1103/physreve.90.052305] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2014] [Indexed: 06/04/2023]
Abstract
We use large scale computer simulations of a glass-forming liquid in which a fraction c of the particles has been permanently pinned. We find that the relaxation dynamics shows an exponential dependence on c. This result can be rationalized by assuming that the configurational entropy of the pinned liquid decreases linearly upon increasing of c. This behavior is discussed in the context of thermodynamic theories for the glass transition, notably the Adam-Gibbs picture and the random first order transition theory. For intermediate and low temperatures we find that the slowing down of the dynamics due to the pinning saturates and that the cooperativity decreases with increasing c, results which indicate that in glass-forming liquids there is a dynamic crossover at which the shape of the relaxing entities changes.
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Affiliation(s)
- Walter Kob
- Laboratoire Charles Coulomb, UMR 5221, Université Montpellier 2 and CNRS, Montpellier, France
| | - Daniele Coslovich
- Laboratoire Charles Coulomb, UMR 5221, Université Montpellier 2 and CNRS, Montpellier, France
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163
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Charbonneau P, Jin Y, Parisi G, Zamponi F. Hopping and the Stokes-Einstein relation breakdown in simple glass formers. Proc Natl Acad Sci U S A 2014; 111:15025-30. [PMID: 25288722 PMCID: PMC4210276 DOI: 10.1073/pnas.1417182111] [Citation(s) in RCA: 65] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
One of the most actively debated issues in the study of the glass transition is whether a mean-field description is a reasonable starting point for understanding experimental glass formers. Although the mean-field theory of the glass transition--like that of other statistical systems--is exact when the spatial dimension d → ∞, the evolution of systems properties with d may not be smooth. Finite-dimensional effects could dramatically change what happens in physical dimensions,d = 2, 3. For standard phase transitions finite-dimensional effects are typically captured by renormalization group methods, but for glasses the corrections are much more subtle and only partially understood. Here, we investigate hopping between localized cages formed by neighboring particles in a model that allows to cleanly isolate that effect. By bringing together results from replica theory, cavity reconstruction, void percolation, and molecular dynamics, we obtain insights into how hopping induces a breakdown of the Stokes-Einstein relation and modifies the mean-field scenario in experimental systems. Although hopping is found to supersede the dynamical glass transition, it nonetheless leaves a sizable part of the critical regime untouched. By providing a constructive framework for identifying and quantifying the role of hopping, we thus take an important step toward describing dynamic facilitation in the framework of the mean-field theory of glasses.
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Affiliation(s)
| | - Yuliang Jin
- Departments of Chemistry and Dipartimento di Fisica, Sapienza Università di Roma, I-00185 Rome, Italy;
| | - Giorgio Parisi
- Dipartimento di Fisica, Sapienza Università di Roma, I-00185 Rome, Italy; Istituto Nazionale di Fisica Nucleare, Sezione di Roma I, Istituto per i Processi Chimico Fisici, Consiglio Nazionale delle Ricerche, I-00185 Rome, Italy; and
| | - Francesco Zamponi
- Laboratoire de Physique Théorique, Ecole Normale Supérieure, UMR 8549 CNRS, 75005 Paris, France
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164
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Dynamical facilitation governs glassy dynamics in suspensions of colloidal ellipsoids. Proc Natl Acad Sci U S A 2014; 111:15362-7. [PMID: 25313030 DOI: 10.1073/pnas.1413384111] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
One of the greatest challenges in contemporary condensed matter physics is to ascertain whether the formation of glasses from liquids is fundamentally thermodynamic or dynamic in origin. Although the thermodynamic paradigm has dominated theoretical research for decades, the purely kinetic perspective of the dynamical facilitation (DF) theory has attained prominence in recent times. In particular, recent experiments and simulations have highlighted the importance of facilitation using simple model systems composed of spherical particles. However, an overwhelming majority of liquids possess anisotropy in particle shape and interactions, and it is therefore imperative to examine facilitation in complex glass formers. Here, we apply the DF theory to systems with orientational degrees of freedom as well as anisotropic attractive interactions. By analyzing data from experiments on colloidal ellipsoids, we show that facilitation plays a pivotal role in translational as well as orientational relaxation. Furthermore, we demonstrate that the introduction of attractive interactions leads to spatial decoupling of translational and rotational facilitation, which subsequently results in the decoupling of dynamical heterogeneities. Most strikingly, the DF theory can predict the existence of reentrant glass transitions based on the statistics of localized dynamical events, called excitations, whose duration is substantially smaller than the structural relaxation time. Our findings pave the way for systematically testing the DF approach in complex glass formers and also establish the significance of facilitation in governing structural relaxation in supercooled liquids.
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165
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Hocky GM, Coslovich D, Ikeda A, Reichman DR. Correlation of local order with particle mobility in supercooled liquids is highly system dependent. PHYSICAL REVIEW LETTERS 2014; 113:157801. [PMID: 25375744 DOI: 10.1103/physrevlett.113.157801] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2014] [Indexed: 06/04/2023]
Abstract
We investigate the connection between local structure and dynamical heterogeneity in supercooled liquids. Through the study of four different models, we show that the correlation between a particle's mobility and the degree of local order in nearby regions is highly system dependent. Our results suggest that the correlation between local structure and dynamics is weak or absent in systems that conform well to the mean-field picture of glassy dynamics and strong in those that deviate from this paradigm. Finally, we investigate the role of order-agnostic point-to-set correlations and reveal that they provide similar information content to local structure measures, at least in the system where local order is most pronounced.
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Affiliation(s)
- Glen M Hocky
- Department of Chemistry, Columbia University, 3000 Broadway, New York, New York 10027, USA
| | - Daniele Coslovich
- CNRS, Laboratoire Charles Coulomb UMR 5221, Montpellier 34095, France and Université Montpellier 2, Laboratoire Charles Coulomb UMR 5221, Montpellier 34095, France
| | - Atsushi Ikeda
- CNRS, Laboratoire Charles Coulomb UMR 5221, Montpellier 34095, France and Université Montpellier 2, Laboratoire Charles Coulomb UMR 5221, Montpellier 34095, France
| | - David R Reichman
- Department of Chemistry, Columbia University, 3000 Broadway, New York, New York 10027, USA
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166
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Li J, Cao Y, Xia C, Kou B, Xiao X, Fezzaa K, Wang Y. Similarity of wet granular packing to gels. Nat Commun 2014; 5:5014. [DOI: 10.1038/ncomms6014] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2014] [Accepted: 08/18/2014] [Indexed: 11/09/2022] Open
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167
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Rodriguez Fris JA, Frechero MA, Appignanesi GA. Relaxation pathway confinement in glassy dynamics. J Chem Phys 2014; 141:114905. [DOI: 10.1063/1.4895608] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- J. A. Rodriguez Fris
- Sección Fisicoquímica, INQUISUR-UNS-CONICET, Universidad Nacional del Sur, Av. Alem 1253, 8000 Bahía Blanca, Argentina
| | - M. A. Frechero
- Sección Fisicoquímica, INQUISUR-UNS-CONICET, Universidad Nacional del Sur, Av. Alem 1253, 8000 Bahía Blanca, Argentina
| | - G. A. Appignanesi
- Sección Fisicoquímica, INQUISUR-UNS-CONICET, Universidad Nacional del Sur, Av. Alem 1253, 8000 Bahía Blanca, Argentina
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168
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Li J, Hu W. Biased diffusion induces coil deformation via a ‘cracking-the-whip’ effect of acceleration generated by dynamic heterogeneity along a polymer chain. POLYM INT 2014. [DOI: 10.1002/pi.4801] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Juan Li
- State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering; Nanjing University; 210093 Nanjing China
- School of Mechanical Engineering; Nanjing Institute of Industry Technology; 210023 Nanjing China
| | - Wenbing Hu
- State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering; Nanjing University; 210093 Nanjing China
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169
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Cicerone MT, Zhong Q, Tyagi M. Picosecond dynamic heterogeneity, hopping, and Johari-Goldstein relaxation in glass-forming liquids. PHYSICAL REVIEW LETTERS 2014; 113:117801. [PMID: 25260005 DOI: 10.1103/physrevlett.113.117801] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2012] [Indexed: 06/03/2023]
Abstract
We show that incoherent quasielastic neutron scattering from molecular liquids reveals a two-state dynamic heterogeneity on a 1 ps time scale, where molecules are either highly confined or are free to undergo relatively large excursions. Data ranging from deep in the glassy state to well above the melting point allows us to observe temperature-dependent population levels and exchange between these two states. A simple physical picture emerges from this data, combined with published work, that provides a mechanism for hopping and for the Johari-Goldstein (β_{JG}) relaxation, and allows us to accurately calculate the diffusion coefficient, D_{T}, and characteristic times for α, and β_{JG} relaxations from ps time scale neutron data.
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Affiliation(s)
- Marcus T Cicerone
- National Institute of Standards and Technology, Gaithersburg, Maryland 20899-8543, USA and Institute for Physical Science and Technology, University of Maryland, College Park, Maryland 20742, USA
| | - Qin Zhong
- National Institute of Standards and Technology, Gaithersburg, Maryland 20899-8543, USA
| | - Madhusudan Tyagi
- National Institute of Standards and Technology, Gaithersburg, Maryland 20899-8543, USA and Department of Materials Science and Engineering, University of Maryland, College Park, Maryland 20742, USA
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170
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Lehmkühler F, Grübel G, Gutt C. Detecting orientational order in model systems by X-ray cross-correlation methods. J Appl Crystallogr 2014. [DOI: 10.1107/s1600576714012424] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
The results of a computational X-ray cross-correlation analysis (XCCA) study on two-dimensional polygonal model structures are presented. This article shows how to detect and identify the orientational order of such systems, demonstrates how to eliminate the influence of the `computational box' on the XCCA results and develops new correlation functions that reflect the sample's orientational order only. For this purpose, the dependence of the correlation functions on the number of polygonal clusters and scattering vector magnitudeqis studied for various types of polygons, including mixtures of polygons and randomly placed particles. An order parameter that describes the orientational order within the sample is defined. Finally, the influence of detector noise and nonplanar wavefronts on the XCCA data is determined, both of which appear to affect the results significantly and have thus to be considered in real experiments.
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171
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Kim J, Sung BJ. Dynamics and spatial correlation of voids in dense two dimensional colloids. J Chem Phys 2014; 141:014502. [DOI: 10.1063/1.4885035] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Affiliation(s)
- Jeongmin Kim
- Department of Chemistry and Research Institute for Basic Science, Sogang University, Seoul 121-742, South Korea
| | - Bong June Sung
- Department of Chemistry and Research Institute for Basic Science, Sogang University, Seoul 121-742, South Korea
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172
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Tong H, Xu N. Order parameter for structural heterogeneity in disordered solids. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2014; 90:010401. [PMID: 25122238 DOI: 10.1103/physreve.90.010401] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2014] [Indexed: 06/03/2023]
Abstract
We construct a structural order parameter from the energy equipartition of normal modes of vibration to quantify the structural heterogeneity in disordered solids. The order parameter exhibits strong spatial correlations with low-temperature dynamics and local structural entropy. To characterize the role of particles with the most defective local structures identified by the order parameter, we pin them and measure the system response. It turns out that particles with the largest value of the order parameter are responsible for the quasilocalized low-frequency vibration, instability, softening, and nonaffinity of disordered solids. The order parameter thus crucially links the heterogeneous structure to low-temperature dynamics and mechanical properties of disordered solids.
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Affiliation(s)
- Hua Tong
- CAS Key Laboratory of Soft Matter Chemistry, Hefei National Laboratory for Physical Sciences at the Microscale, and Department of Physics, University of Science and Technology of China, Hefei 230026, People's Republic of China
| | - Ning Xu
- CAS Key Laboratory of Soft Matter Chemistry, Hefei National Laboratory for Physical Sciences at the Microscale, and Department of Physics, University of Science and Technology of China, Hefei 230026, People's Republic of China
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173
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Kawasaki T, Tanaka H. Structural evolution in the aging process of supercooled colloidal liquids. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2014; 89:062315. [PMID: 25019784 DOI: 10.1103/physreve.89.062315] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2013] [Indexed: 06/03/2023]
Abstract
When a liquid is rapidly quenched to a temperature below the glass-transition point, it is driven out of equilibrium; it then slowly relaxes to a (quasi)equilibrium state. This slow relaxation process is called aging. By definition, any glasses are inevitably in the process of aging and actually slowly evolving with time. Thus the study of aging phenomena is of fundamental importance for understanding not only the nonequilibrium nature of the glass transition, but also the stability of glassy materials. Here we consider aging after a rather shallow quench, for which a system is still able to reach (metastable) equilibrium. By using polydisperse colloidal liquids as a model, we show the validity of dynamical scaling that there is only one relevant length scale not only for a quasiequilibrium supercooled state but also for a nonequilibrium process of aging, which is reminiscent of dynamical critical phenomena. Our finding indicates that the aging toward (metastable) equilibrium may be regarded as the growth process of critical-like fluctuations of static order associated with low-free-energy configurations, further suggesting that this ordering is the origin of cooperative slow dynamics in the systems studied. The generality of this statement for other glass-forming systems remains for a future study.
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Affiliation(s)
- Takeshi Kawasaki
- Institute of Industrial Science, University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8505, Japan
| | - Hajime Tanaka
- Institute of Industrial Science, University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8505, Japan
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174
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Structural signatures of dynamic heterogeneities in monolayers of colloidal ellipsoids. Nat Commun 2014; 5:3829. [PMID: 24807069 PMCID: PMC4024749 DOI: 10.1038/ncomms4829] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2013] [Accepted: 04/08/2014] [Indexed: 11/21/2022] Open
Abstract
When a liquid is supercooled towards the glass transition, its dynamics drastically slows down, whereas its static structure remains relatively unchanged. Finding a structural signature of the dynamic slowing down is a major challenge, yet it is often too subtle to be uncovered. Here we discover the structural signatures for both translational and rotational dynamics in monolayers of colloidal ellipsoids by video microscopy experiments and computer simulations. The correlation lengths of the dynamic slowest-moving clusters, the static glassy clusters, the static local structural entropy and the dynamic heterogeneity follow the same power-law divergence, suggesting that the kinetic slowing down is caused by a decrease in the structural entropy and an increase in the size of the glassy cluster. Ellipsoids with different aspect ratios exhibit single- or double-step glass transitions with distinct dynamic heterogeneities. These findings demonstrate that the particle shape anisotropy has important effects on the structure and dynamics of the glass. To establish a structural signature of slow dynamics as a system approaches the glass transition is challenging. Here, the authors identify, by performing video microscopy experiments and simulations, two structural signatures for the rotational and translational dynamics in monolayers of colloidal ellipsoids.
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175
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Cangialosi D. Dynamics and thermodynamics of polymer glasses. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2014; 26:153101. [PMID: 24675099 DOI: 10.1088/0953-8984/26/15/153101] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The fate of matter when decreasing the temperature at constant pressure is that of passing from gas to liquid and, subsequently, from liquid to crystal. However, a class of materials can exist in an amorphous phase below the melting temperature. On cooling such materials, a glass is formed; that is, a material with the rigidity of a solid but exhibiting no long-range order. The study of the thermodynamics and dynamics of glass-forming systems is the subject of continuous research. Within the wide variety of glass formers, an important sub-class is represented by glass forming polymers. The presence of chain connectivity and, in some cases, conformational disorder are unfavourable factors from the point of view of crystallization. Furthermore, many of them, such as amorphous thermoplastics, thermosets and rubbers, are widely employed in many applications. In this review, the peculiarities of the thermodynamics and dynamics of glass-forming polymers are discussed, with particular emphasis on those topics currently the subject of debate. In particular, the following aspects will be reviewed in the present work: (i) the connection between the pronounced slowing down of glassy dynamics on cooling towards the glass transition temperature (Tg) and the thermodynamics; and, (ii) the fate of the dynamics and thermodynamics below Tg. Both aspects are reviewed in light of the possible presence of a singularity at a finite temperature with diverging relaxation time and zero configurational entropy. In this context, the specificity of glass-forming polymers is emphasized.
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Affiliation(s)
- D Cangialosi
- Materials Physics Center, Paseo Manuel de Lardizabel 5 20018 San Sebastian, Spain
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176
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Qiao J, Casalini R, Pelletier JM, Kato H. Characteristics of the structural and Johari-Goldstein relaxations in Pd-based metallic glass-forming liquids. J Phys Chem B 2014; 118:3720-30. [PMID: 24611812 DOI: 10.1021/jp4121782] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The dynamics of Pd-based metallic glass-forming liquids (Pd(40)Ni(10)Cu(30)P(20), Pd(42.5)Ni(7.5)Cu(30)P(20), Pd(40)Ni(40)P(20), and Pd(30)Ni(50)P(20)) was studied by mechanical spectroscopy and modulated differential scanning calorimetry (MDSC). We found that the change in composition has a significant effect on the α relaxation dynamics; the largest difference corresponds to an increase of the glass transition temperature Tg of ∼ 15 K, for materials in which 30% Ni was substituted by 30% Cu (i.e., from Pd(40)Ni(40)P(20) to Pd(40)Ni(10)Cu(30)P(20)). We also found that all Pd-based metallic glasses have very similar fragilities, 59 < m < 67, and Kohlrausch stretched exponents, 0.59 < βKWW < 0.60. It is interesting that the values of m and βKWW correlate well with the general relation proposed by Böhmer et al. for nonmetallic glass formers (Böhmer, R.; et al. J. Chem. Phys. 1993, 99, 4201-4209), which for the observed βKWW values predicts 58 < m < 61. From a linear deconvolution of the α and β relaxations, we find that the substitution of the Ni with Cu induced a large change in the time constant of the Johari-Goldstein relaxation, τβ. The activation energy, Uβ, of the β relaxation was largely independent of chemical composition. In all cases, 25 < Uβ/RT < 28, a range in agreement with results for other glass formers (Kudlik, A.; et al. Europhys. Lett. 1997, 40, 649-654 and Ngai, K. L.; et al. Phys. Rev. E 2004, 69, 031501). From the heat capacity and mechanical loss, estimates were obtained for the number of dynamically correlated units, Nc; we find significantly larger values for these metallic glass-forming liquids than Nc for other glass-forming materials.
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Affiliation(s)
- Jichao Qiao
- Université de Lyon , MATEIS, UMR CNRS5510, Bat. B. Pascal, INSA-Lyon, F-69621 Villeurbanne cedex, France
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177
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Understanding water's anomalies with locally favoured structures. Nat Commun 2014; 5:3556. [PMID: 24694550 DOI: 10.1038/ncomms4556] [Citation(s) in RCA: 197] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2013] [Accepted: 03/05/2014] [Indexed: 12/17/2022] Open
Abstract
Water is a complex liquid that displays a surprising array of unusual properties, the most famous being the density maximum at about 4 °C. The origin of these anomalies is still a matter of debate, and so far a quantitative description of water's phase behaviour starting from the molecular arrangements is still missing. Here we report a study of the microscopic structural features of water as obtained from computer simulations. We identify locally favoured structures having a high degree of translational order in the second shell, and a two-state model is used to describe the behaviour of liquid water over a wide region of the phase diagram. Furthermore, we show that locally favoured structures not only have translational order in the second shell but also contain five-membered rings of hydrogen-bonded molecules. This suggests their mixed character: the former helps crystallization, whereas the latter causes frustration against crystallization.
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178
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Langer JS. Theories of glass formation and the glass transition. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2014; 77:042501. [PMID: 24646953 DOI: 10.1088/0034-4885/77/4/042501] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
This key-issues review is a plea for a new focus on simpler and more realistic models of glass-forming fluids. It seems to me that we have too often been led astray by sophisticated mathematical models that beautifully capture some of the most intriguing features of glassy behavior, but are too unrealistic to provide bases for predictive theories. As illustrations of what I mean, the first part of this article is devoted to brief summaries of imaginative, sensible, but disparate and often contradictory ideas for solving glass problems. Almost all of these ideas remain alive today, with their own enthusiastic advocates. I then describe numerical simulations, mostly by H Tanaka and coworkers, in which it appears that very simple, polydisperse systems of hard disks and spheres develop long range, Ising-like, bond-orientational order as they approach glass transitions. Finally, I summarize my recent proposal that topologically ordered clusters of particles, in disordered environments, tend to become aligned with each other as if they were two-state systems, and thus produce the observed Ising-like behavior. Neither Tanaka's results nor my proposed interpretation of them fit comfortably within any of the currently popular glass theories.
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Affiliation(s)
- J S Langer
- Department of Physics, University of California, Santa Barbara, CA 93106-9530, USA
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179
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Schwenke K, Isa L, Del Gado E. Assembly of nanoparticles at liquid interfaces: crowding and ordering. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2014; 30:3069-74. [PMID: 24564671 DOI: 10.1021/la404254n] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Experiments with the self-assembly of nanoparticles at liquid interfaces suggest that cooperative and slow dynamical processes due to particle crowding at the interface govern the adsorption and properties of the final assembly. Here we report a numerical approach to studying nonequilibrium adsorption, which elucidates these experimental observations. The analysis of particle rearrangements shows that local ordering processes are directly related to adsorption events at high interface coverage. Interestingly, this feature and the mechanism coupling local ordering to adsorption do not seem to change qualitatively upon increasing particle size polydispersity, although the latter changes the interface microstructure and its final properties. Our results indicate how adsorption kinetics can be used for the fabrication of 2D nanocomposites with controlled microstructure.
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Affiliation(s)
- Konrad Schwenke
- Department of Civil, Environmental and Geomatic Engineering, and §Laboratory for Interfaces, Soft Matter and Assembly, Department of Materials, ETH Zürich , 8093 Zurich, Switzerland
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180
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Takae K, Onuki A. Orientational glass in mixtures of elliptic and circular particles: structural heterogeneities, rotational dynamics, and rheology. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2014; 89:022308. [PMID: 25353473 DOI: 10.1103/physreve.89.022308] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2013] [Indexed: 06/04/2023]
Abstract
Using molecular dynamics simulation with an angle-dependent Lennard-Jones potential, we study orientational glass with quadrupolar symmetry in mixtures of elliptic particles and circular impurities in two dimensions. With a mild aspect ratio (= 1.23) and a mild size ratio (= 1.2), we realize a plastic crystal at relatively high temperature T. With further lowering T, we find a structural phase transition for very small impurity concentration c and pinned disordered orientations for not small c. The ellipses are anchored by the impurities in the planar alignment. With increasing c, the orientation domains composed of isosceles triangles gradually become smaller, resulting in orientational glass with crystal order. In our simulation, the impurity distribution becomes heterogeneous during quenching from liquid, which then produces rotational dynamic heterogeneities. We also examine rheology in orientational glass to predict a shape memory effect and a superelasticity effect, where a large fraction of the strain is due to collective orientation changes.
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Affiliation(s)
- Kyohei Takae
- Department of Physics, Kyoto University, Kyoto 606-8502, Japan
| | - Akira Onuki
- Department of Physics, Kyoto University, Kyoto 606-8502, Japan
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181
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Zanatta M, Baldi G, Brusa RS, Egger W, Fontana A, Gilioli E, Mariazzi S, Monaco G, Ravelli L, Sacchetti F. Structural evolution and medium range order in permanently densified vitreous SiO2. PHYSICAL REVIEW LETTERS 2014; 112:045501. [PMID: 24580465 DOI: 10.1103/physrevlett.112.045501] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2013] [Indexed: 06/03/2023]
Abstract
Positron annihilation lifetime spectroscopy is employed to measure the size of the interstitial void spaces characterizing the structure of a set of permanently densified SiO2 glasses. The average volume of the voids is markedly affected by the densification process and linearly shrinks by almost an order of magnitude after a relative density variation of 22%. In addition, x-ray diffraction shows that this change of density does not modify appreciably the short range order, which remains organized in SiO4 tetrahedra. These results strongly suggest a porous medium description for v-SiO2 glasses where the compressibility and the medium range order are dominated by the density variation of the voids volume up to densities close to that of α-quartz.
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Affiliation(s)
- M Zanatta
- Dipartimento di Fisica, Università di Perugia, I-06123 Perugia, Italy
| | - G Baldi
- IMEM-CNR, I-43124 Parma, Italy
| | - R S Brusa
- Dipartimento di Fisica, Università di Trento, I-38123 Povo, Trento, Italy
| | - W Egger
- Institut für Angewandte Physik und Messtechnik, Universität der Bundeswehr München, D-85577 Neubiberg, Germany
| | - A Fontana
- Dipartimento di Fisica, Università di Trento, I-38123 Povo, Trento, Italy
| | | | - S Mariazzi
- Dipartimento di Fisica, Università di Trento, I-38123 Povo, Trento, Italy
| | - G Monaco
- Dipartimento di Fisica, Università di Trento, I-38123 Povo, Trento, Italy
| | - L Ravelli
- Institut für Angewandte Physik und Messtechnik, Universität der Bundeswehr München, D-85577 Neubiberg, Germany
| | - F Sacchetti
- Dipartimento di Fisica, Università di Perugia, I-06123 Perugia, Italy and IOM-CNR c/o Dipartimento di Fisica, Università di Perugia, I-06123 Perugia, Italy
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182
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Malins A, Williams SR, Eggers J, Royall CP. Identification of structure in condensed matter with the topological cluster classification. J Chem Phys 2013; 139:234506. [DOI: 10.1063/1.4832897] [Citation(s) in RCA: 95] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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183
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Liquid-liquid-solid transition in viscoelastic liquids. Sci Rep 2013; 3:1323. [PMID: 23429528 PMCID: PMC3579185 DOI: 10.1038/srep01323] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2012] [Accepted: 02/07/2013] [Indexed: 12/05/2022] Open
Abstract
Liquid-liquid-solid transitions (LLST) are known to occur in confined liquids, exist in supercooled liquids and emerge in liquids driven from equilibrium. Molecular dynamics (MD) simulations claim many successes in forecasting the phenomena. The transitions are also studied in the framework of thermodynamics based methods and minimalistic models. In here, the proposed approach is derived in the framework of continuum and includes spatial and temporal dynamic heterogeneities; the approach is meant to capture the material behavior at small scales. We conjecture that the liquid-like and solid-like behaviors are dissimilar enough for the two to be governed by different constitutive relations. In this way, we gain additional degree of freedom, which is found essential when predicting the transitional phenomena. As a result, we derive the LLST criteria for liquids in equilibrium, during steady flow and at transient conditions. Lastly, we forecast short-lived LLSTs in human blood during cardiac cycle.
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184
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Shiba H, Kawasaki T. Spatiotemporal heterogeneity of local free volumes in highly supercooled liquid. J Chem Phys 2013; 139:184502. [PMID: 24320279 DOI: 10.1063/1.4829442] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
We discuss the spatiotemporal behavior of local density and its relation to dynamical heterogeneity in a highly supercooled liquid by using molecular dynamics simulations of a binary mixture with different particle sizes in two dimensions. To trace voids heterogeneously existing with lower local densities, which move along with the structural relaxation, we employ the minimum local density for each particle in a time window whose width is set along with the structural relaxation time. Particles subject to free volumes correspond well to the configuration rearranging region of dynamical heterogeneity. While the correlation length for dynamical heterogeneity grows with temperature decrease, no growth in the correlation length of heterogeneity in the minimum local density distribution takes place. A comparison of these results with those of normal mode analysis reveals that superpositions of lower-frequency soft modes extending over the free volumes exhibit spatial correlation with the broken bonds. This observation suggests a possibility that long-ranged vibration modes facilitate the interactions between fragile regions represented by free volumes, to induce dynamical correlations at a large scale.
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Affiliation(s)
- Hayato Shiba
- Institute for Solid State Physics, University of Tokyo, Chiba 277-8581, Japan
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185
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Lechner W, Zoller P. From classical to quantum glasses with ultracold polar molecules. PHYSICAL REVIEW LETTERS 2013; 111:185306. [PMID: 24237535 DOI: 10.1103/physrevlett.111.185306] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2013] [Indexed: 06/02/2023]
Abstract
We study the dynamics of a bilayer system of ultracold polar molecules, which exhibits classical and quantum glassy behavior, characterized by long tails in the relaxation time and dynamical heterogeneity. In the proposed setup, quantum fluctuations are of the order of thermal fluctuations and the degree of frustration can be tuned by the interlayer distance. We discuss the possible observation of a glassy anomalous diffusion and dynamical heterogeneity in experiment using internal degrees of freedom of the molecules in combination with optical detection.
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Affiliation(s)
- Wolfgang Lechner
- Institute for Quantum Optics and Quantum Information, Austrian Academy of Sciences, 6020 Innsbruck, Austria and Institute for Theoretical Physics, University of Innsbruck, 6020 Innsbruck, Austria
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186
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Han Y, Lee J, Choi SQ, Choi MC, Kim MW. Shape-induced chiral ordering in two-dimensional packing of snowmanlike dimeric particles. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2013; 88:042202. [PMID: 24229162 DOI: 10.1103/physreve.88.042202] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2013] [Indexed: 06/02/2023]
Abstract
Understanding the distinctive phase behaviors in random packing due to particle shapes is an important issue in condensed matter physics. In this paper, we investigate the random packing structure of two-dimensional (2D) snowmen via wax-snowman packing experiments and Brownian dynamics simulations. Both experiments and simulations reveal that neighboring snowmen have a strong short-range orientational correlation and consequently locally form particular conformations. A chiral conformation is dominant for high area fractions near the jamming condition (φ>0.8), and the proportion of the chiral conformation increases with γ. We also found that the attractive interaction does not have a significant impact on the results. The geometry of chirally ordered snowmen causes a mismatch with 2D crystalline symmetries and thus inhibits the development of long-range spatial order, despite the strong orientational correlation between neighbors.
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Affiliation(s)
- Youngkyu Han
- Department of Physics, KAIST, Daejeon 305-701, Korea
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187
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Kang H, Kirkpatrick TR, Thirumalai D. Manifestation of random first-order transition theory in Wigner glasses. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2013; 88:042308. [PMID: 24229173 DOI: 10.1103/physreve.88.042308] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2012] [Revised: 07/21/2013] [Indexed: 06/02/2023]
Abstract
We use Brownian dynamics simulations of a binary mixture of highly charged spherical colloidal particles to test some of the predictions of the random first-order transition (RFOT) theory [Phys. Rev. Lett. 58, 2091 (1987); Phys. Rev. A 40, 1045 (1989)]. In accord with mode-coupling theory and RFOT, we find that as the volume fraction of the colloidal particles ϕ approaches the dynamical transition value ϕ(A), three measures of dynamics show an effective ergodic to nonergodic transition. First, there is a dramatic slowing down of diffusion, with the translational diffusion constant decaying as a power law as ϕ→ϕ(A)(-). Second, the energy metric, a measure of ergodicity breaking in classical many-body systems, shows that the system becomes effectively nonergodic as ϕ(A) is approached. Finally, the time t(*), at which the four-point dynamical susceptibility achieves a maximum, also increases as a power law near ϕ(A). Remarkably, the translational diffusion coefficients, ergodic diffusion coefficient, and (t(*))(-) all vanish as (ϕ(-1)-ϕ(A)(-1))(γ) with both ϕ(A)(≈0.1) and γ being the roughly the same for all three quantities. Above ϕ(A), transport involves crossing free energy barriers. In this regime, the density-density correlation function decays as a stretched exponential [exp-(t/τ(α))(β)] with β≈0.45. The ϕ dependence of the relaxation time τ(α) could be fit using the Vogel-Tamman-Fulcher law with the ideal glass transition at ϕ(K)≈0.47. By using a local entropy measure, we show that the law of large numbers is not obeyed above ϕ(A), and gives rise to subsample to subsample fluctuations in all physical observables. We propose that dynamical heterogeneity is a consequence of violation of law of large numbers.
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Affiliation(s)
- Hongsuk Kang
- Institute for Physical Science and Technology, University of Maryland, College Park, Maryland 20742, USA
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188
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Massiot D, Messinger RJ, Cadars S, Deschamps M, Montouillout V, Pellerin N, Veron E, Allix M, Florian P, Fayon F. Topological, geometric, and chemical order in materials: insights from solid-state NMR. Acc Chem Res 2013; 46:1975-84. [PMID: 23883113 DOI: 10.1021/ar3003255] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Unlike the long-range order of ideal crystalline structures, local order is an intrinsic characteristic of real materials and often serves as the key to the tuning of their properties and their final applications. Although researchers can easily assess local ordering using two-dimensional imaging techniques with resolution that approaches the atomic level, the diagnosis, description, and qualification of local order in three dimensions is much more challenging. Solid-state nuclear magnetic resonance (NMR) and its panel of continually developing instruments and methods enable the local, atom-selective characterization of structures and assemblies ranging from the atomic to the nanometer length scales. By making use of the indirect J-coupling that distinguishes chemical bonds, researchers can use solid-state NMR to characterize a variety of materials, ranging from crystalline compounds to amorphous or glassy materials. In crystalline compounds showing some disorder, we describe and distinguish the contributions of topology, geometry, and local chemistry in ways that are consistent with X-ray diffraction and computational approaches. We give examples of materials featuring either chemical disorder in a topological order or topological disorder with local chemical order. For glasses, we show that we can separate geometric and chemical contributions to the local order by identifying structural motifs with a viewpoint that extends from the atomic scale up to the nanoscale. As identified by solid state NMR, the local structure of amorphous materials or glasses consists of well-identified structural entities up to at least the nanometer scale. Instead of speaking of disorder, we propose a new description for these structures as a continuous assembly of locally defined structures, an idea that draws on the concept of locally favored structures (LFS) introduced by Tanaka and coworkers. This idea provides a comprehensive picture of amorphous structures based on fluctuations of chemical composition and structure over different length scales. We hope that these local or molecular insights will allow researchers to consider key questions related to nucleation and crystallization, as well as chemically (spinodal decomposition) or density-driven (polyamorphism) phase separation, which could lead to future applications in a variety of materials.
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Affiliation(s)
- Dominique Massiot
- CNRS, CEMHTI, UPR 3079, F-45071, Orléans, France, and University of Orléans, CEMHTI, UPR CNRS 3079, F-45071, Orléans, France
| | - Robert J. Messinger
- CNRS, CEMHTI, UPR 3079, F-45071, Orléans, France, and University of Orléans, CEMHTI, UPR CNRS 3079, F-45071, Orléans, France
| | - Sylvian Cadars
- CNRS, CEMHTI, UPR 3079, F-45071, Orléans, France, and University of Orléans, CEMHTI, UPR CNRS 3079, F-45071, Orléans, France
| | - MichaËl Deschamps
- CNRS, CEMHTI, UPR 3079, F-45071, Orléans, France, and University of Orléans, CEMHTI, UPR CNRS 3079, F-45071, Orléans, France
| | - Valerie Montouillout
- CNRS, CEMHTI, UPR 3079, F-45071, Orléans, France, and University of Orléans, CEMHTI, UPR CNRS 3079, F-45071, Orléans, France
| | - Nadia Pellerin
- CNRS, CEMHTI, UPR 3079, F-45071, Orléans, France, and University of Orléans, CEMHTI, UPR CNRS 3079, F-45071, Orléans, France
| | - Emmanuel Veron
- CNRS, CEMHTI, UPR 3079, F-45071, Orléans, France, and University of Orléans, CEMHTI, UPR CNRS 3079, F-45071, Orléans, France
| | - Mathieu Allix
- CNRS, CEMHTI, UPR 3079, F-45071, Orléans, France, and University of Orléans, CEMHTI, UPR CNRS 3079, F-45071, Orléans, France
| | - Pierre Florian
- CNRS, CEMHTI, UPR 3079, F-45071, Orléans, France, and University of Orléans, CEMHTI, UPR CNRS 3079, F-45071, Orléans, France
| | - Franck Fayon
- CNRS, CEMHTI, UPR 3079, F-45071, Orléans, France, and University of Orléans, CEMHTI, UPR CNRS 3079, F-45071, Orléans, France
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189
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Starr FW, Douglas JF, Sastry S. The relationship of dynamical heterogeneity to the Adam-Gibbs and random first-order transition theories of glass formation. J Chem Phys 2013; 138:12A541. [PMID: 23556792 DOI: 10.1063/1.4790138] [Citation(s) in RCA: 182] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We carefully examine common measures of dynamical heterogeneity for a model polymer melt and test how these scales compare with those hypothesized by the Adam and Gibbs (AG) and random first-order transition (RFOT) theories of relaxation in glass-forming liquids. To this end, we first analyze clusters of highly mobile particles, the string-like collective motion of these mobile particles, and clusters of relative low mobility. We show that the time scale of the high-mobility clusters and strings is associated with a diffusive time scale, while the low-mobility particles' time scale relates to a structural relaxation time. The difference of the characteristic times for the high- and low-mobility particles naturally explains the well-known decoupling of diffusion and structural relaxation time scales. Despite the inherent difference of dynamics between high- and low-mobility particles, we find a high degree of similarity in the geometrical structure of these particle clusters. In particular, we show that the fractal dimensions of these clusters are consistent with those of swollen branched polymers or branched polymers with screened excluded-volume interactions, corresponding to lattice animals and percolation clusters, respectively. In contrast, the fractal dimension of the strings crosses over from that of self-avoiding walks for small strings, to simple random walks for longer, more strongly interacting, strings, corresponding to flexible polymers with screened excluded-volume interactions. We examine the appropriateness of identifying the size scales of either mobile particle clusters or strings with the size of cooperatively rearranging regions (CRR) in the AG and RFOT theories. We find that the string size appears to be the most consistent measure of CRR for both the AG and RFOT models. Identifying strings or clusters with the "mosaic" length of the RFOT model relaxes the conventional assumption that the "entropic droplets" are compact. We also confirm the validity of the entropy formulation of the AG theory, constraining the exponent values of the RFOT theory. This constraint, together with the analysis of size scales, enables us to estimate the characteristic exponents of RFOT.
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Affiliation(s)
- Francis W Starr
- Physics Department, Wesleyan University, Middletown, Connecticut 06459, USA
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190
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Bolmatov D, Brazhkin VV, Trachenko K. Thermodynamic behaviour of supercritical matter. Nat Commun 2013; 4:2331. [DOI: 10.1038/ncomms3331] [Citation(s) in RCA: 92] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2013] [Accepted: 07/19/2013] [Indexed: 11/09/2022] Open
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191
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Langer JS. Ising model of a glass transition. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2013; 88:012122. [PMID: 23944429 DOI: 10.1103/physreve.88.012122] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2013] [Revised: 06/19/2013] [Indexed: 06/02/2023]
Abstract
Numerical simulations by Tanaka and co-workers indicate that glass-forming systems of moderately polydisperse hard-core particles, in both two and three dimensions, exhibit diverging correlation lengths. These correlations are described by Ising-like critical exponents, and are associated with diverging, Vogel-Fulcher-Tamann, structural relaxation times. Related simulations of thermalized hard disks indicate that the curves of pressure versus packing fraction for different polydispersities exhibit a sequence of transition points, starting with a liquid-hexatic transition for the monodisperse case, and crossing over with increasing polydispersity to glassy, Ising-like critical points. I propose to explain these observations by assuming that glass-forming fluids contain twofold degenerate, locally ordered clusters of particles, similar to the two-state systems that have been invoked to explain other glassy phenomena. This paper starts with a brief statistical derivation of the thermodynamics of thermalized, hard-core particles. It then discusses how a two-state, Ising-like model can be described within that framework in terms of a small number of statistically relevant, internal state variables. The resulting theory agrees accurately with the simulation data. I also propose a rationale for the observed relation between the Ising-like correlation lengths and the Vogel-Fulcher-Tamann formula.
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Affiliation(s)
- J S Langer
- Department of Physics, University of California, Santa Barbara, California 93106-9530, USA
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192
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Hung PK, Ha NTT, Lan MT, Hong NV. Spatial heterogeneous distribution of SiO(x) → SiO(x±1) reactions in silica liquid. J Chem Phys 2013; 138:244505. [PMID: 23822254 DOI: 10.1063/1.4811491] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We have numerically studied the diffusion mechanism in silica liquid following an approach where the diffusion rate is evaluated via the SiO(x) → SiO(x±1) reaction rate υ(react) and the mean square displacement of particles d(react) as a reaction happens. Five models at pressure up to 25 GPa and at a temperature of 3000 K have been constructed by molecular dynamic simulation. When applying pressure to the liquid, υ(react) increases monotonously because the Si-O bond becomes weaker with pressure. Meanwhile d(react) attains a maximum near the point of 10 GPa despite the particles move in a significantly smaller volume. Furthermore, the SiO(x) → SiO(x±1) reactions are spatially heterogeneously distributed in the liquid. Upon low pressure, most reactions happen with a small number of Si particles. This reaction localization causes the diffusion anomaly and dynamics heterogeneity in the liquid. With increasing pressure the diffusion mechanism changes from the heterogeneous spatial distribution of reactions to homogeneous one. The simulation also reveals two distinguished regions with quite different coordination environments where the reaction rate significantly differs from each other. These sets of Si particles migrate in space over time and form regions with so-called "fast" and "slow" Si particles. The result obtained here indicates the coexistence of low- and high-density regions, and supports the concept of polymorphism in silica liquid.
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Affiliation(s)
- P K Hung
- Department of Computational Physics, Hanoi University of Science and Technology, Hanoi, Vietnam.
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193
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Furukawa A. Simple picture of supercooled liquid dynamics: dynamic scaling and phenomenology based on clusters. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2013; 87:062321. [PMID: 23848689 DOI: 10.1103/physreve.87.062321] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2012] [Revised: 03/10/2013] [Indexed: 06/02/2023]
Abstract
Although it is now well established that in glassy liquids, slow structural relaxation accompanies a correlated structural rearrangement, the role of such a correlation in the transport anomaly, and thus in the slow dynamics, remains unclear. In this paper, we argue from a hydrodynamic viewpoint that a correlated structure (cluster) with a characteristic size ξ sustains the long-lived stress and dynamically couples with the hydrodynamic fluctuations; therefore, the dynamics of this cluster is the origin of the mesoscopic nature of anomalous hydrodynamic transport. Based on this argument, we derive a dynamic scaling law for τ(α) (or η, where η is the macroscopic shear viscosity) as a function of ξ: τ(α)([proportionality]η)[proportionality]ξ(4). We provide a simple explanation for basic features of anomalous transport, such as the breakdown of the Stokes-Einstein relation and the length-scale-dependent decoupling between viscosity and diffusion. The present study further suggests a different physical picture: Through the coarse graining of smaller-scale fluctuations (</~ξ), the supercooled liquid dynamics can be regarded as the dynamics of normal (cluster) liquids composed of units with a typical size of ξ. Although the correlation length of hydrodynamic transport ξ and the dynamic heterogeneity size ξ(DH), which is determined by the usual four-point correlation function, reflect some aspects of the cooperative effects, the correspondence between ξ and ξ(DH) is not one to one. We highlight the possibility that ξ(DH) overestimates the actual collective transport range at a low degree of supercooling.
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Affiliation(s)
- Akira Furukawa
- Institute of Industrial Science, University of Tokyo, Tokyo 153-8505, Japan.
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194
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Napolitano S, Capponi S, Vanroy B. Glassy dynamics of soft matter under 1D confinement: how irreversible adsorption affects molecular packing, mobility gradients and orientational polarization in thin films. THE EUROPEAN PHYSICAL JOURNAL. E, SOFT MATTER 2013; 36:61. [PMID: 23797356 DOI: 10.1140/epje/i2013-13061-8] [Citation(s) in RCA: 131] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2013] [Revised: 05/14/2013] [Accepted: 05/17/2013] [Indexed: 06/02/2023]
Abstract
The structural dynamics of polymers and simple liquids confined at the nanometer scale has been intensively investigated in the last two decades in order to test the validity of theories on the glass transition predicting a characteristic length scale of a few nanometers. Although this goal has not yet been reached, the anomalous behavior displayed by some systems--e.g. thin films of polystyrene exhibit reductions of Tg exceeding 70 K and a tremendous increase in the elastic modulus--has attracted a broad community of researchers, and provided astonishing advancement of both theoretical and experimental soft matter physics. 1D confinement is achieved in thin films, which are commonly treated as systems at thermodynamic equilibrium where free surfaces and solid interfaces introduce monotonous mobility gradients, extending for several molecular sizes. Limiting the discussion to finite-size and interfacial effects implies that film thickness and surface interactions should be sufficient to univocally determine the deviation from bulk behavior. On the contrary, such an oversimplified picture, although intuitive, cannot explain phenomena like the enhancement of segmental mobility in proximity of an adsorbing interface, or the presence of long-lasting metastable states in the liquid state. Based on our recent work, we propose a new picture on the dynamics of soft matter confined in ultrathin films, focusing on non-equilibrium and on the impact of irreversibly chain adsorption on the structural relaxation. We describe the enhancement of dynamics in terms of the excess in interfacial free volume, originating from packing frustration in the adsorbed layer (Guiselin brush) at t(*) ≪ 1, where t(*) is the ratio between the annealing time and the time scale of adsorption. Prolonged annealing at times exceeding the reptation time (usually t(*) ≫ 1 induces densification, and thus reduces the deviation from bulk behavior. In this Colloquium, after reviewing the experimental approaches permitting to investigate the structural relaxation of films with one, two or no free surfaces by means of dielectric spectroscopy, we propose several methods to determine gradients of mobility in thin films, and then discuss on the unexploited potential of analyses based on the time, temperature and thickness dependence of the orientational polarization via the dielectric strength.
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Affiliation(s)
- Simone Napolitano
- Laboratory of Polymer and Soft Matter Dynamics, Faculté des Sciences, Université Libre de Bruxelles, Boulevard du Triomphe, Bâtiment NO, 1050, Bruxelles, Belgium.
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195
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Baldi G, Zanatta M, Gilioli E, Milman V, Refson K, Wehinger B, Winkler B, Fontana A, Monaco G. Emergence of crystal-like atomic dynamics in glasses at the nanometer scale. PHYSICAL REVIEW LETTERS 2013; 110:185503. [PMID: 23683216 DOI: 10.1103/physrevlett.110.185503] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2012] [Indexed: 06/02/2023]
Abstract
The vibrational dynamics of a permanently densified silica glass is compared to the one of an α-quartz polycrystal, the silica polymorph of the same density and local structure. The combined use of inelastic x-ray scattering experiments and ab initio numerical calculations provides compelling evidence of a transition, in the glass, from the isotropic elastic response at long wavelengths to a microscopic regime as the wavelength decreases below a characteristic length ξ of a few nanometers, corresponding to about 20 interatomic distances. In the microscopic regime the glass vibrations closely resemble those of the polycrystal, with excitations related to the acoustic and optic modes of the crystal. A coherent description of the experimental results is obtained assuming that the elastic modulus of the glass presents spatial heterogeneities of an average size a ~ ξ/2 π.
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Affiliation(s)
- G Baldi
- CNR-IMEM Institute, Parma Science Park, I-43124 Parma, Italy.
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196
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Kawasaki T, Onuki A. Dynamics of thermal vibrational motions and stringlike jump motions in three-dimensional glass-forming liquids. J Chem Phys 2013; 138:12A514. [DOI: 10.1063/1.4770337] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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197
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Leocmach M, Russo J, Tanaka H. Importance of many-body correlations in glass transition: An example from polydisperse hard spheres. J Chem Phys 2013; 138:12A536. [DOI: 10.1063/1.4769981] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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198
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Kapko V, Zhao Z, Matyushov DV, Austen Angell C. “Ideal glassformers” vs “ideal glasses”: Studies of crystal-free routes to the glassy state by “potential tuning” molecular dynamics, and laboratory calorimetry. J Chem Phys 2013; 138:12A549. [DOI: 10.1063/1.4794787] [Citation(s) in RCA: 10] [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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199
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Kim K, Saito S. Multiple length and time scales of dynamic heterogeneities in model glass-forming liquids: A systematic analysis of multi-point and multi-time correlations. J Chem Phys 2013; 138:12A506. [DOI: 10.1063/1.4769256] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
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200
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Malins A, Eggers J, Royall CP, Williams SR, Tanaka H. Identification of long-lived clusters and their link to slow dynamics in a model glass former. J Chem Phys 2013; 138:12A535. [DOI: 10.1063/1.4790515] [Citation(s) in RCA: 94] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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