1
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Lutsko JF, Schoonen C. A microscopic approach to crystallization: Challenging the classical/non-classical dichotomy. J Chem Phys 2024; 161:104502. [PMID: 39254162 DOI: 10.1063/5.0225658] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2024] [Accepted: 08/26/2024] [Indexed: 09/11/2024] Open
Abstract
We present a fundamental framework for the study of crystallization based on a combination of classical density functional theory and fluctuating hydrodynamics that is free of any assumptions regarding order parameters and that requires no input other than molecular interaction potentials. We use it to study the nucleation of both droplets and crystalline solids from a low-concentration solution of colloidal particles using two different interaction potentials. We find that the nucleation pathways of both droplets and crystals are remarkably similar at the early stages of nucleation until they diverge due to a rapid ordering along the solid pathways in line with the paradigm of "non-classical" crystallization. We compute the unstable modes at the critical clusters and find that despite the non-classical nature of solid nucleation, the size of the nucleating clusters remains the principle order parameter in all cases, supporting a "classical" description of the dynamics of crystallization. We show that nucleation rates can be extracted from our formalism in a systematic way. Our results suggest that in some cases, despite the non-classical nature of the nucleation pathways, classical nucleation theory can give reasonable results for solids but that there are circumstances where it may fail. This contributes a nuanced perspective to recent experimental and simulation work, suggesting that important aspects of crystal nucleation can be described within a classical framework.
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Affiliation(s)
- James F Lutsko
- Center for Nonlinear Phenomena and Complex Systems CP 231, Université Libre de Bruxelles, Blvd. du Triomphe, 1050 Brussels, Belgium
| | - Cédric Schoonen
- Center for Nonlinear Phenomena and Complex Systems CP 231, Université Libre de Bruxelles, Blvd. du Triomphe, 1050 Brussels, Belgium
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2
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Bouzid O, Martínez-Fernández D, Herranz M, Karayiannis NC. Entropy-Driven Crystallization of Hard Colloidal Mixtures of Polymers and Monomers. Polymers (Basel) 2024; 16:2311. [PMID: 39204531 PMCID: PMC11359749 DOI: 10.3390/polym16162311] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2024] [Revised: 08/05/2024] [Accepted: 08/11/2024] [Indexed: 09/04/2024] Open
Abstract
The most trivial example of self-assembly is the entropy-driven crystallization of hard spheres. Past works have established the similarities and differences in the phase behavior of monomers and chains made of hard spheres. Inspired by the difference in the melting points of the pure components, we study, through Monte Carlo simulations, the phase behavior of athermal mixtures composed of fully flexible polymers and individual monomers of uniform size. We analyze how the relative number fraction and the packing density affect crystallization and the established ordered morphologies. As a first result, a more precise determination of the melting point for freely jointed chains of tangent hard spheres is extracted. A synergetic effect is observed in the crystallization leading to synchronous crystallization of the two species. Structural analysis of the resulting ordered morphologies shows perfect mixing and thus no phase separation. Due to the constraints imposed by chain connectivity, the local environment of the individual spheres, as quantified by the Voronoi polyhedron, is systematically more spherical and more symmetric compared to that of spheres belonging to chains. In turn, the local environment of the ordered phase is more symmetric and more spherical compared to that of the initial random packing, demonstrating the entropic origins of the phase transition. In general, increasing the polymer content reduces the degree of crystallinity and increases the melting point to higher volume fractions. According to the present findings, relative concentration is another determining factor in controlling the phase behavior of hard colloidal mixtures based on polymers.
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Affiliation(s)
- Olia Bouzid
- Institute for Optoelectronic Systems and Microtechnology (ISOM) and Escuela Técnica Superior de Ingenieros Industriales (ETSII), Universidad Politécnica de Madrid (UPM), José Gutierrez Abascal 2, 28006 Madrid, Spain
| | - Daniel Martínez-Fernández
- Institute for Optoelectronic Systems and Microtechnology (ISOM) and Escuela Técnica Superior de Ingenieros Industriales (ETSII), Universidad Politécnica de Madrid (UPM), José Gutierrez Abascal 2, 28006 Madrid, Spain
| | - Miguel Herranz
- Institute for Optoelectronic Systems and Microtechnology (ISOM) and Escuela Técnica Superior de Ingenieros Industriales (ETSII), Universidad Politécnica de Madrid (UPM), José Gutierrez Abascal 2, 28006 Madrid, Spain
| | - Nikos Ch Karayiannis
- Institute for Optoelectronic Systems and Microtechnology (ISOM) and Escuela Técnica Superior de Ingenieros Industriales (ETSII), Universidad Politécnica de Madrid (UPM), José Gutierrez Abascal 2, 28006 Madrid, Spain
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3
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Sun G, Tanaka H. Surface-induced water crystallisation driven by precursors formed in negative pressure regions. Nat Commun 2024; 15:6083. [PMID: 39060256 PMCID: PMC11282091 DOI: 10.1038/s41467-024-50188-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Accepted: 06/26/2024] [Indexed: 07/28/2024] Open
Abstract
Ice nucleation is a crucial process in nature and industries; however, the role of the free surface of water in this process remains unclear. To address this, we investigate the microscopic freezing process using brute-force molecular dynamics simulations. We discover that the free surface assists ice nucleation through an unexpected mechanism. The surface-induced negative pressure enhances the formation of local structures with a ring topology characteristic of Ice 0-like symmetry, promoting ice nucleation despite the symmetry differing from ordinary ice crystals. Unlike substrate-induced nucleation via water-solid interactions that occurs directly on the surface, this negative-pressure-induced mechanism promotes ice nucleation slightly inward the surface. Our findings provide a molecular-level understanding of the mechanism and pathway behind free-surface-induced ice formation, resolving the longstanding debate. The implications of our discoveries are of substantial importance in areas such as cloud formation, food technology, and other fields where ice nucleation plays a pivotal role.
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Affiliation(s)
- Gang Sun
- Social Cooperation Research Department "Frost Protection Science", Institute of Industrial Science, The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo, Japan
- Center for Advanced Quantum Studies, Department of Physics, Beijing Normal University, Beijing, China
| | - Hajime Tanaka
- Department of Fundamental Engineering, Institute of Industrial Science, The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo, Japan.
- Research Center for Advanced Science and Technology, The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo, Japan.
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4
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Martirossyan MM, Spellings M, Pan H, Dshemuchadse J. Local Structural Features Elucidate Crystallization of Complex Structures. ACS NANO 2024; 18:14989-15002. [PMID: 38815007 DOI: 10.1021/acsnano.4c01290] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2024]
Abstract
Complex crystal structures are composed of multiple local environments, and how this type of order emerges spontaneously during crystal growth has yet to be fully understood. We study crystal growth across various structures and along different crystallization pathways, using self-assembly simulations of identical particles that interact via multiwell isotropic pair potentials. We apply an unsupervised machine learning method to features from bond-orientational order metrics to identify different local motifs present during a given structure's crystallization process. In this manner, we distinguish different crystallographic sites in highly complex structures. Tailoring this order parameter to structures of varying complexity and coordination number, we study the emergence of local order along a multistep crystal growth pathway─from a low-density fluid to a high-density, supercooled amorphous liquid droplet and to a bulk crystal. We find a consistent under-coordination of the liquid relative to the average coordination number in the bulk crystal. We use our order parameter to analyze the geometrically frustrated growth of a Frank-Kasper phase and discover how structural defects compete with the formation of crystallographic sites that are more high-coordinated than the liquid environments. The method presented here for classifying order on a particle-by-particle level has broad applicability to future studies of structural self-assembly and crystal growth, and they can aid in the design of building blocks and for targeting pathways of formation of soft-matter structures.
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Affiliation(s)
- Maya M Martirossyan
- Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, United States
| | - Matthew Spellings
- Vector Institute for Artificial Intelligence, Toronto, Ontario M5G 1M1, Canada
| | - Hillary Pan
- Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, United States
| | - Julia Dshemuchadse
- Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, United States
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5
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Hoy RS. Homogeneous crystallization in four-dimensional Lennard-Jones liquids. Phys Rev E 2024; 109:044604. [PMID: 38755930 DOI: 10.1103/physreve.109.044604] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2023] [Accepted: 03/25/2024] [Indexed: 05/18/2024]
Abstract
We observe homogeneous crystallization in simulated high-dimensional (d>3) liquids that follow physically realistic dynamics and have system sizes that are large enough to eliminate the possibility that crystallization was induced by the periodic boundary conditions. Supercooled four-dimensional (4D) Lennard-Jones (LJ) liquids maintained at zero pressure and constant temperatures 0.59
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Affiliation(s)
- Robert S Hoy
- Department of Physics, University of South Florida, Tampa, Florida 33620, USA
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6
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Men H. A molecular dynamics study on the boundary between homogeneous and heterogeneous nucleation. J Chem Phys 2024; 160:094702. [PMID: 38426521 DOI: 10.1063/5.0192069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2023] [Accepted: 02/17/2024] [Indexed: 03/02/2024] Open
Abstract
The large discrepancy among the nucleation kinetics extracted from experimental measurements and computer simulations and the prediction of the classical nucleation theory (CNT) has stimulated intense arguments about its origin in the past decades, which is crucially relevant to the validity of the CNT. In this paper, we investigate the atomistic mechanism of the nucleation in liquid Al in contact with amorphous substrates with atomic-level smooth/rough surfaces, using molecular dynamics (MD) simulations. This study reveals that the slightly distorted local fcc/hcp structures in amorphous substrates with smooth surfaces can promote heterogeneous nucleation through a structural templating mechanism, and on the other hand, homogeneous nucleation will occur at a larger undercooling through a fluctuation mechanism if the surface is rough. Thus, some impurities, previously thought to be impotent, could be activated in the homogeneous nucleation experiments. We further find that the initial growth of the nucleus on smooth surfaces of amorphous substrates is one order of magnitude faster than that in homogeneous nucleation. Both these factors could significantly contribute to the discrepancy in the nucleation kinetics. This study is also supported by a recent study of the synthesis of high-entropy alloy nanoparticles assisted with the liquid metal Ga [Cao et al., Nature 619, 73 (2023)]. In this study, we established that the boundary existed between homogeneous and heterogeneous nucleation, i.e., the structural templating is a general mechanism for heterogeneous nucleation, and in its absence, homogeneous nucleation will occur through the fluctuation mechanism. This study provides an in-depth understanding of the nucleation theory and experiments.
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Affiliation(s)
- Hua Men
- BCAST, Brunel University London, Uxbridge, Middlesex UB8 3PH, United Kingdom
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7
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Sato M. Formation of various structures caused by particle size difference in colloidal heteroepitaxy. Sci Rep 2024; 14:3245. [PMID: 38331999 PMCID: PMC10853232 DOI: 10.1038/s41598-024-53850-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2023] [Accepted: 02/06/2024] [Indexed: 02/10/2024] Open
Abstract
By performing isothermal-isochoric Monte Carlo simulations with depletion force, the author investigated the dependence of the epitxial layer structure on the differences in the particle size between the substrate in colloidal heteroepitaxy. By changing the size of epitaxial particles and performing simulations comprehensively, various structures including the structures observed in a experiment, such as a honeycomb, one created by hexagonal heptamers, and one consisting of both pentagonal tiles and triangular tiles, were created. When the ratio of particle sizes between the epitxial layer and substrate takes a specific value, two types of hexagonal structures were created. One is the hexagonal layer parallel to the substrate layer and the other layer is rotated by 60[Formula: see text] from the substrate layer. The former structure was created over a wide range of particle-size ratios, whereas the latter structure was created when the particle-size ratio was only around the specific ratio, and it seemed a metastable structure.
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Affiliation(s)
- Masahide Sato
- Emerging Media Initiative, Kanazawa University, Kanazawa, 920-1192, Japan.
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8
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Fan Z, Tanaka H. Microscopic mechanisms of pressure-induced amorphous-amorphous transitions and crystallisation in silicon. Nat Commun 2024; 15:368. [PMID: 38228606 DOI: 10.1038/s41467-023-44332-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Accepted: 12/08/2023] [Indexed: 01/18/2024] Open
Abstract
Some low-coordination materials, including water, silica, and silicon, exhibit polyamorphism, having multiple amorphous forms. However, the microscopic mechanism and kinetic pathway of amorphous-amorphous transition (AAT) remain largely unknown. Here, we use a state-of-the-art machine-learning potential and local structural analysis to investigate the microscopic kinetics of AAT in silicon after a rapid pressure change. We find that the transition from low-density-amorphous (LDA) to high-density-amorphous (HDA) occurs through nucleation and growth, resulting in non-spherical interfaces that underscore the mechanical nature of AAT. In contrast, the reverse transition occurs through spinodal decomposition. Further pressurisation transforms LDA into very-high-density amorphous (VHDA), with HDA serving as an intermediate state. Notably, the final amorphous states are inherently unstable, transitioning into crystals. Our findings demonstrate that AAT and crystallisation are driven by joint thermodynamic and mechanical instabilities, assisted by preordering, occurring without diffusion. This unique mechanical and diffusion-less nature distinguishes AAT from liquid-liquid transitions.
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Affiliation(s)
- Zhao Fan
- Research Center for Advanced Science and Technology, The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo, 153-8904, Japan
| | - Hajime Tanaka
- Research Center for Advanced Science and Technology, The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo, 153-8904, Japan.
- Department of Fundamental Engineering, Institute of Industrial Science, University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo, 153-8505, Japan.
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9
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Ruzzi V, Baglioni J, Piazza R. Optothermal crystallization of hard spheres in an effective bidimensional geometry. J Chem Phys 2023; 159:154904. [PMID: 37850694 DOI: 10.1063/5.0169221] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Accepted: 10/01/2023] [Indexed: 10/19/2023] Open
Abstract
Using colloids effectively confined in two dimensions by a cell with a thickness comparable to the particle size, we investigate the nucleation and growth of crystallites induced by locally heating the solvent with a near-infrared laser beam. The particles, which are "thermophilic," move towards the laser spot solely because of thermophoresis with no convection effects, forming dense clusters whose structure is monitored using two order parameters that gauge the local density and the orientational ordering. We find that ordering takes place when the cluster reaches an average surface density that is still below the upper equilibrium limit for the fluid phase of hard disks, meaning that we do not detect any sign of a proper "two-stage" nucleation from a glass or a polymorphic crystal structure. The crystal obtained at late growth stage displays a remarkable uniformity with a negligible amount of defects, arguably because the incoming particles diffuse, bounce, and displace other particles before settling at the crystal interface. This "fluidization" of the outer crystal edge may resemble the surface enhanced mobility giving rise to ultra-stable glasses by physical vapor deposition.
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Affiliation(s)
- Vincenzo Ruzzi
- Department of Chemistry, Materials Science, and Chemical Engineering (CMIC) "Giulio Natta," Politecnico di Milano, Edificio 6, Piazza Leonardo da Vinci 32, 20133 Milano, Italy
| | - Jacopo Baglioni
- Department of Chemistry, Materials Science, and Chemical Engineering (CMIC) "Giulio Natta," Politecnico di Milano, Edificio 6, Piazza Leonardo da Vinci 32, 20133 Milano, Italy
| | - Roberto Piazza
- Department of Chemistry, Materials Science, and Chemical Engineering (CMIC) "Giulio Natta," Politecnico di Milano, Edificio 6, Piazza Leonardo da Vinci 32, 20133 Milano, Italy
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10
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de Jager M, Smallenburg F, Filion L. In search of a precursor for crystal nucleation of hard and charged colloids. J Chem Phys 2023; 159:134902. [PMID: 37787142 DOI: 10.1063/5.0161356] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2023] [Accepted: 09/13/2023] [Indexed: 10/04/2023] Open
Abstract
The interplay between crystal nucleation and the structure of the metastable fluid has been a topic of significant debate over recent years. In particular, it has been suggested that even in simple model systems such as hard or charged colloids, crystal nucleation might be foreshadowed by significant fluctuations in local structure around the location where the nucleus first arises. We investigate this using computer simulations of spontaneous nucleation events in both hard and charged colloidal systems. To detect local structural variations, we use both standard and unsupervised machine learning methods capable of finding hidden structures in the metastable fluid phase. We track numerous nucleation events for the face-centered cubic and body-centered cubic crystals on a local level and demonstrate that all signs of crystallinity emerge simultaneously from the very start of the nucleation process. We thus conclude that we observe no precursor for the crystal nucleation of hard and charged colloids.
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Affiliation(s)
- Marjolein de Jager
- Soft Condensed Matter, Debye Institute of Nanomaterials Science, Utrecht University, Utrecht, The Netherlands
| | - Frank Smallenburg
- Université Paris-Saclay, CNRS, Laboratoire de Physique des Solides, 91405 Orsay, France
| | - Laura Filion
- Soft Condensed Matter, Debye Institute of Nanomaterials Science, Utrecht University, Utrecht, The Netherlands
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11
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Ouyang W, Zou S, Zhong J, Xu S. Template-induced crystallization of charged colloids: a molecular dynamics study. SOFT MATTER 2023; 19:6329-6340. [PMID: 37564036 DOI: 10.1039/d3sm00872j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/12/2023]
Abstract
By using a large enough number of particles and implementing a parallel algorithm on the CUDA platform, we have performed brute-force molecular dynamics simulations to study the template-induced heterogeneous crystallization in charged colloids. Six kinds of templates, whose patterns include the planes of fcc(100), fcc(110), fcc(111), bcc(100), bcc(110) and bcc(111), have been implanted into the middle of the simulation box. Except the fcc(111) template, whose structure benefits not only fcc but also hcp crystals resulting in a similar behavior to homogeneous crystallization, bcc-type templates favor the formation of bcc crystals and bcc-like precursors while fcc-type templates favor the formation of fcc crystals and fcc-like precursors. Therefore, for fcc(100) and fcc(110) templates, heterogeneous crystallization will definitely result in a fcc crystallite. However, the results of heterogeneous crystallization that are induced by bcc-type templates are subtly different at different state points. At the state points where the interaction strength of charged colloids is weak and the fcc phase is thermodynamically stable, the bcc crystals formed with the promotion of bcc-type templates are not stable so as to tend to transform into fcc or hcp crystals. When the interaction strength of charged colloids is high, the predominant bcc crystals formed with the promotion of bcc-type templates can always persist within the time scale of simulation although not bcc but fcc crystals are thermodynamically stable.
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Affiliation(s)
- Wenze Ouyang
- Key Laboratory of Microgravity, Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190, China.
| | - Shuangyang Zou
- Key Laboratory of Microgravity, Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190, China.
| | - Jun Zhong
- College of Materials Engineering, North China Institute of Aerospace Engineering, Langfang 065000, China
| | - Shenghua Xu
- Key Laboratory of Microgravity, Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190, China.
- School of Engineering Science, University of Chinese Academy of Sciences, Beijing 100049, China
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12
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Striker NN, Lokteva I, Dartsch M, Dallari F, Goy C, Westermeier F, Markmann V, Hövelmann SC, Grübel G, Lehmkühler F. Dynamics and Time Scales of Higher-Order Correlations in Supercooled Colloidal Systems. J Phys Chem Lett 2023; 14:4719-4725. [PMID: 37171882 DOI: 10.1021/acs.jpclett.3c00631] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
The dynamics and time scales of higher-order correlations are studied in supercooled colloidal systems. A combination of X-ray photon correlation spectroscopy (XPCS) and X-ray cross-correlation analysis (XCCA) shows the typical slowing of the dynamics of a hard sphere system when approaching the glass transition. The time scales of higher-order correlations are probed using a novel time correlation function gC, tracking the time evolution of cross-correlation function C. With an increasing volume fraction, the ratio of relaxation times of gC to the standard individual particle relaxation time obtained by XPCS increases from ∼0.4 to ∼0.9. While a value of ∼0.5 is expected for free diffusion, the increasing values suggest that the local orders within the sample are becoming more long-lived for larger volume fractions. Furthermore, the dynamics of local order is more heterogeneous than the individual particle dynamics. These results indicate that not only the presence but also the lifetime of locally favored structures increases close to the glass transition.
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Affiliation(s)
- Nele N Striker
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany
| | - Irina Lokteva
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany
- The Hamburg Centre for Ultrafast Imaging, Luruper Chaussee 149, 22761 Hamburg, Germany
| | - Michael Dartsch
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany
- The Hamburg Centre for Ultrafast Imaging, Luruper Chaussee 149, 22761 Hamburg, Germany
| | - Francesco Dallari
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany
| | - Claudia Goy
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany
| | - Fabian Westermeier
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany
| | - Verena Markmann
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany
| | - Svenja C Hövelmann
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany
- Institut für Experimentelle und Angewandte Physik, Christian-Albrechts-Universität zu Kiel, Leibnizstraße 19, 24098 Kiel, Germany
| | - Gerhard Grübel
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany
- The Hamburg Centre for Ultrafast Imaging, Luruper Chaussee 149, 22761 Hamburg, Germany
| | - Felix Lehmkühler
- 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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13
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Martínez-Fernández D, Herranz M, Foteinopoulou K, Karayiannis NC, Laso M. Local and Global Order in Dense Packings of Semi-Flexible Polymers of Hard Spheres. Polymers (Basel) 2023; 15:polym15030551. [PMID: 36771852 PMCID: PMC9919756 DOI: 10.3390/polym15030551] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Revised: 01/16/2023] [Accepted: 01/17/2023] [Indexed: 01/24/2023] Open
Abstract
The local and global order in dense packings of linear, semi-flexible polymers of tangent hard spheres are studied by employing extensive Monte Carlo simulations at increasing volume fractions. The chain stiffness is controlled by a tunable harmonic potential for the bending angle, whose intensity dictates the rigidity of the polymer backbone as a function of the bending constant and equilibrium angle. The studied angles range between acute and obtuse ones, reaching the limit of rod-like polymers. We analyze how the packing density and chain stiffness affect the chains' ability to self-organize at the local and global levels. The former corresponds to crystallinity, as quantified by the Characteristic Crystallographic Element (CCE) norm descriptor, while the latter is computed through the scalar orientational order parameter. In all cases, we identify the critical volume fraction for the phase transition and gauge the established crystal morphologies, developing a complete phase diagram as a function of packing density and equilibrium bending angle. A plethora of structures are obtained, ranging between random hexagonal closed packed morphologies of mixed character and almost perfect face centered cubic (FCC) and hexagonal close-packed (HCP) crystals at the level of monomers, and nematic mesophases, with prolate and oblate mesogens at the level of chains. For rod-like chains, a delay is observed between the establishment of the long-range nematic order and crystallization as a function of the packing density, while for right-angle chains, both transitions are synchronized. A comparison is also provided against the analogous packings of monomeric and fully flexible chains of hard spheres.
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14
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Neha, Tiwari V, Mondal S, Kumari N, Karmakar T. Collective Variables for Crystallization Simulations-from Early Developments to Recent Advances. ACS OMEGA 2023; 8:127-146. [PMID: 36643553 PMCID: PMC9835087 DOI: 10.1021/acsomega.2c06310] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Accepted: 12/08/2022] [Indexed: 03/11/2024]
Abstract
Crystallization is an important physicochemical process which has relevance in material science, biology, and the environment. Decades of experimental and theoretical efforts have been made to understand this fundamental symmetry-breaking transition. While experiments provide equilibrium structures and shapes of crystals, they are limited to unraveling how molecules aggregate to form crystal nuclei that subsequently transform into bulk crystals. Computer simulations, mainly molecular dynamics (MD), can provide such microscopic details during the early stage of a crystallization event. Crystallization is a rare event that takes place in time scales much longer than a typical equilibrium MD simulation can sample. This inadequate sampling of the MD method can be easily circumvented by the use of enhanced sampling (ES) simulations. In most of the ES methods, the fluctuations of a system's slow degrees of freedom, called collective variables (CVs), are enhanced by applying a bias potential. This transforms the system from one state to the other within a short time scale. The most crucial part of such CV-based ES methods is to find suitable CVs, which often needs intuition and several trial-and-error optimization steps. Over the years, a plethora of CVs has been developed and applied in the study of crystallization. In this review, we provide a brief overview of CVs that have been developed and used in ES simulations to study crystallization from melt or solution. These CVs can be categorized mainly into four types: (i) spherical particle-based, (ii) molecular template-based, (iii) physical property-based, and (iv) CVs obtained from dimensionality reduction techniques. We present the context-based evolution of CVs, discuss the current challenges, and propose future directions to further develop effective CVs for the study of crystallization of complex systems.
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Affiliation(s)
| | | | | | | | - Tarak Karmakar
- Department of Chemistry, Indian Institute of Technology, Delhi, Hauz Khas, New Delhi110016, India
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15
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Jakse N, Sandberg J, Granz LF, Saliou A, Jarry P, Devijver E, Voigtmann T, Horbach J, Meyer A. Machine learning interatomic potentials for aluminium: application to solidification phenomena. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2022; 51:035402. [PMID: 36301702 DOI: 10.1088/1361-648x/ac9d7d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2022] [Accepted: 10/25/2022] [Indexed: 06/16/2023]
Abstract
In studying solidification process by simulations on the atomic scale, the modeling of crystal nucleation or amorphization requires the construction of interatomic interactions that are able to reproduce the properties of both the solid and the liquid states. Taking into account rare nucleation events or structural relaxation under deep undercooling conditions requires much larger length scales and longer time scales than those achievable byab initiomolecular dynamics (AIMD). This problem is addressed by means of classical molecular dynamics simulations using a well established high dimensional neural network potential trained on a set of configurations generated by AIMD relevant for solidification phenomena. Our dataset contains various crystalline structures and liquid states at different pressures, including their time fluctuations in a wide range of temperatures. Applied to elemental aluminium, the resulting potential is shown to be efficient to reproduce the basic structural, dynamics and thermodynamic quantities in the liquid and undercooled states. Early stages of crystallization are further investigated on a much larger scale with one million atoms, allowing us to unravel features of the homogeneous nucleation mechanisms in the fcc phase at ambient pressure as well as in the bcc phase at high pressure with unprecedented accuracy close to theab initioone. In both cases, a single step nucleation process is observed.
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Affiliation(s)
- Noel Jakse
- Université Grenoble Alpes, CNRS, Grenoble INP, SIMaP, F-38000 Grenoble, France
| | - Johannes Sandberg
- Université Grenoble Alpes, CNRS, Grenoble INP, SIMaP, F-38000 Grenoble, France
- Institut für Materialphysik im Weltraum, Deutsches Zentrum für Luft- und Raumfahrt (DLR), 51170 Köln, Germany
- Department of Physics, Heinrich-Heine-Universität Düsseldorf, Universitätsstraße 1, 40225 Düsseldorf, Germany
| | - Leon F Granz
- Institut für Materialphysik im Weltraum, Deutsches Zentrum für Luft- und Raumfahrt (DLR), 51170 Köln, Germany
- Department of Physics, Heinrich-Heine-Universität Düsseldorf, Universitätsstraße 1, 40225 Düsseldorf, Germany
| | - Anthony Saliou
- Université Grenoble Alpes, CNRS, Grenoble INP, SIMaP, F-38000 Grenoble, France
| | - Philippe Jarry
- C-TEC, Parc Economique Centr'alp, 725 rue Aristide Bergès, CS10027, Voreppe 38341 CEDEX, France
| | - Emilie Devijver
- Université Grenoble Alpes, CNRS, Grenoble INP, LIG, F-38000 Grenoble, France
| | - Thomas Voigtmann
- Institut für Materialphysik im Weltraum, Deutsches Zentrum für Luft- und Raumfahrt (DLR), 51170 Köln, Germany
- Department of Physics, Heinrich-Heine-Universität Düsseldorf, Universitätsstraße 1, 40225 Düsseldorf, Germany
| | - Jürgen Horbach
- Institut für Theoretische Physik II, Heinrich-Heine-Universität Düsseldorf, Universitätsstraße 1, 40225 Düsseldorf, Germany
| | - Andreas Meyer
- Institut für Materialphysik im Weltraum, Deutsches Zentrum für Luft- und Raumfahrt (DLR), 51170 Köln, Germany
- Institut Laue-Langevin (ILL), 38042 Grenoble, France
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16
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Herranz M, Foteinopoulou K, Karayiannis NC, Laso M. Polymorphism and Perfection in Crystallization of Hard Sphere Polymers. Polymers (Basel) 2022; 14:polym14204435. [PMID: 36298013 PMCID: PMC9612263 DOI: 10.3390/polym14204435] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2022] [Revised: 10/12/2022] [Accepted: 10/14/2022] [Indexed: 11/24/2022] Open
Abstract
We present results on polymorphism and perfection, as observed in the spontaneous crystallization of freely jointed polymers of hard spheres, obtained in an unprecedentedly long Monte Carlo (MC) simulation on a system of 54 chains of 1000 monomers. Starting from a purely amorphous configuration, after an initial dominance of the hexagonal closed packed (HCP) polymorph and a transitory random hexagonal close packed (rHCP) morphology, the system crystallizes in a final, stable, face centered cubic (FCC) crystal of very high perfection. An analysis of chain conformational characteristics, of the spatial distribution of monomers and of the volume accessible to them shows that the phase transition is caused by an increase in translational entropy that is larger than the loss of conformational entropy of the chains in the crystal, compared to the amorphous state. In spite of the significant local re-arrangements, as reflected in the bending and torsion angle distributions, the average chain size remains unaltered during crystallization. Polymers in the crystal adopt ideal random walk statistics as their great length renders local conformational details, imposed by the geometry of the FCC crystal, irrelevant.
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Affiliation(s)
| | | | - Nikos Ch. Karayiannis
- Correspondence: (N.C.K.); (M.L.); Tel.: +34-910677318 (N.C.K.); +34-910677320 (M.L.)
| | - Manuel Laso
- Correspondence: (N.C.K.); (M.L.); Tel.: +34-910677318 (N.C.K.); +34-910677320 (M.L.)
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17
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Hu YC, Tanaka H. Revealing the role of liquid preordering in crystallisation of supercooled liquids. Nat Commun 2022; 13:4519. [PMID: 35927419 PMCID: PMC9352720 DOI: 10.1038/s41467-022-32241-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Accepted: 07/21/2022] [Indexed: 11/09/2022] Open
Abstract
The recent discovery of non-classical crystal nucleation pathways has revealed the role of fluctuations in the liquid structural order, not considered in classical nucleation theory. On the other hand, classical crystal growth theory states that crystal growth is independent of interfacial energy, but this is questionable. Here we elucidate the role of liquid structural ordering in crystal nucleation and growth using computer simulations of supercooled liquids. We find that suppressing the crystal-like structural order in the supercooled liquid through a new order-killing strategy can reduce the crystallisation rate by several orders of magnitude. This indicates that crystal-like liquid preordering and the associated interfacial energy reduction play an essential role in nucleation and growth processes, forcing critical modifications of the classical crystal growth theory. Furthermore, we evaluate the importance of this additional factor for different types of liquids. These findings shed new light on the fundamental understanding of crystal growth kinetics.
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Affiliation(s)
- Yuan-Chao Hu
- Department of Fundamental Engineering, Institute of Industrial Science, University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo, 153-8505, Japan
| | - Hajime Tanaka
- Department of Fundamental Engineering, Institute of Industrial Science, University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo, 153-8505, Japan. .,Research Center for Advanced Science and Technology, University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo, 153-8904, Japan.
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18
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Ramos PM, Herranz M, Martínez-Fernández D, Foteinopoulou K, Laso M, Karayiannis NC. Crystallization of Flexible Chains of Tangent Hard Spheres under Full Confinement. J Phys Chem B 2022; 126:5931-5947. [PMID: 35904560 DOI: 10.1021/acs.jpcb.2c03424] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
We present results from extensive Monte Carlo simulations on the crystallization of athermal polymers under full confinement. Polymers are represented as freely jointed chains of tangent hard spheres of uniform size. Confinement is applied through the presence of flat, parallel, and impenetrable walls in all dimensions. We analyze crystallization as the summation of two contributions: one that occurs in the bulk volume of the system (bulk crystallization), and one on the wall surfaces (surface crystallization). Depending on volume fraction initially amorphous (disordered) hard-sphere chain packings transit to the stable crystal phase. The established ordered morphologies consist primarily of hexagonal close-packed (HCP) crystals in the bulk volume and of triangular (TRI) crystals on the surface. As in the case of athermal packings in the bulk (without confinement), a structural competition is observed between the 5-fold local symmetry and the formation of close-packed crystallites. Effectively, the full confinement inside a cube favors the growth of the HCP crystal, as the FCC one is quite incompatible with the imposed spatial constraints. Consequently, we observe the formation of noncompact ordered motifs which grow from the surface to the inner volume of the simulation cell. We further compare the 2D and 3D crystals formed by monomeric hard spheres under the same simulation conditions. Significant differences are observed at low densities that tend to diminish as concentration increases.
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Affiliation(s)
- Pablo Miguel Ramos
- Institute for Optoelectronic Systems and Microtechnology (ISOM) and Escuela Técnica Superior de Ingenieros Industriales (ETSII), Universidad Politécnica de Madrid (UPM), José Gutiérrez Abascal 2, 28006 Madrid, Spain
| | - Miguel Herranz
- Institute for Optoelectronic Systems and Microtechnology (ISOM) and Escuela Técnica Superior de Ingenieros Industriales (ETSII), Universidad Politécnica de Madrid (UPM), José Gutiérrez Abascal 2, 28006 Madrid, Spain
| | - Daniel Martínez-Fernández
- Institute for Optoelectronic Systems and Microtechnology (ISOM) and Escuela Técnica Superior de Ingenieros Industriales (ETSII), Universidad Politécnica de Madrid (UPM), José Gutiérrez Abascal 2, 28006 Madrid, Spain
| | - Katerina Foteinopoulou
- Institute for Optoelectronic Systems and Microtechnology (ISOM) and Escuela Técnica Superior de Ingenieros Industriales (ETSII), Universidad Politécnica de Madrid (UPM), José Gutiérrez Abascal 2, 28006 Madrid, Spain
| | - Manuel Laso
- Institute for Optoelectronic Systems and Microtechnology (ISOM) and Escuela Técnica Superior de Ingenieros Industriales (ETSII), Universidad Politécnica de Madrid (UPM), José Gutiérrez Abascal 2, 28006 Madrid, Spain
| | - Nikos Ch Karayiannis
- Institute for Optoelectronic Systems and Microtechnology (ISOM) and Escuela Técnica Superior de Ingenieros Industriales (ETSII), Universidad Politécnica de Madrid (UPM), José Gutiérrez Abascal 2, 28006 Madrid, Spain
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19
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Gui Y, Huang C, Shi C, Stelzer T, Zhang GGZ, Yu L. Polymorphic selectivity in crystal nucleation. J Chem Phys 2022; 156:144504. [DOI: 10.1063/5.0086308] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Crystal nucleation rates have been measured in the supercooled melts of two richly polymorphic glass-forming liquids: ROY and nifedipine (NIF). ROY or 5-methyl-2-[(2-nitrophenyl)amino]-3-thiophenecarbonitrile is known for its crystals of red, orange, and yellow colors and many polymorphs of solved structures (12). Of the many polymorphs, ON (orange needles) nucleates the fastest with the runner up (Y04) trailing by a factor of 103 when compared under the same mobility-limited condition, while the other unobserved polymorphs are slower yet by at least 5 orders of magnitude. Similarly, of the six polymorphs of NIF, [Formula: see text]′ nucleates the fastest, [Formula: see text]′ is slower by a factor of 10, and the rest are slower yet by at least 5 decades. In both systems, the faster-nucleating polymorphs are not built from the lowest-energy conformers, while they tend to have higher energies and lower densities and thus greater similarity to the liquid phase by these measures. The temperature ranges of this study covered the glass transition temperature Tg of each system, and we find no evidence that the nucleation rate is sensitive to the passage of Tg. At the lowest temperatures investigated, the rates of nucleation and growth are proportional to each other, indicating that a similar kinetic barrier controls both processes. The classical nucleation theory provides an accurate description of the observed nucleation rates if the crystal growth rate is used to describe the kinetic barrier for nucleation. The quantitative rates of both nucleation and growth for the competing polymorphs enable prediction of the overall rate of crystallization and its polymorphic outcome.
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Affiliation(s)
- Yue Gui
- School of Pharmacy, University of Wisconsin-Madison, Madison, Wisconsin 53705, USA
| | - Chengbin Huang
- School of Pharmacy, University of Wisconsin-Madison, Madison, Wisconsin 53705, USA
| | - Chenyang Shi
- Drug Product Development, Research and Development, AbbVie, Inc., North Chicago, Illinois 60064, USA
| | - Torsten Stelzer
- Department of Pharmaceutical Sciences, University of Puerto Rico, Medical Sciences Campus, San Juan, Puerto Rico 00936, USA
- Crystallization Design Institute, Molecular Sciences Research Center, University of Puerto Rico, San Juan, Puerto Rico 00926, USA
| | - Geoff G. Z. Zhang
- Drug Product Development, Research and Development, AbbVie, Inc., North Chicago, Illinois 60064, USA
| | - Lian Yu
- School of Pharmacy, University of Wisconsin-Madison, Madison, Wisconsin 53705, USA
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20
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Becker S, Devijver E, Molinier R, Jakse N. Unsupervised topological learning for identification of atomic structures. Phys Rev E 2022; 105:045304. [PMID: 35590625 DOI: 10.1103/physreve.105.045304] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Accepted: 03/04/2022] [Indexed: 06/15/2023]
Abstract
We propose an unsupervised learning methodology with descriptors based on topological data analysis (TDA) concepts to describe the local structural properties of materials at the atomic scale. Based only on atomic positions and without a priori knowledge, our method allows for an autonomous identification of clusters of atomic structures through a Gaussian mixture model. We apply successfully this approach to the analysis of elemental Zr in the crystalline and liquid states as well as homogeneous nucleation events under deep undercooling conditions. This opens the way to deeper and autonomous study of complex phenomena in materials at the atomic scale.
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Affiliation(s)
- Sébastien Becker
- University of Grenoble Alpes, CNRS, Grenoble INP, SIMaP, F-38000 Grenoble, France
- University of Grenoble Alpes, CNRS, Grenoble INP, LIG, F-38000 Grenoble, France
| | - Emilie Devijver
- University of Grenoble Alpes, CNRS, Grenoble INP, LIG, F-38000 Grenoble, France
| | - Rémi Molinier
- University of Grenoble Alpes, CNRS, IF, F-38000 Grenoble, France
| | - Noël Jakse
- University of Grenoble Alpes, CNRS, Grenoble INP, SIMaP, F-38000 Grenoble, France
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21
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Holder J, Schmid R, Nielaba P. Two-step nucleation in confined geometry: Phase diagram of finite particles on a lattice gas model. J Chem Phys 2022; 156:124504. [DOI: 10.1063/5.0073043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
We use a degenerated Ising model to describe nucleation and crystallization from solution in a confined two-component system. The free energy is calculated using metadynamics simulation with coordination numbers as the reaction coordinates. We deploy nudged elastic band simulation to determine the minimum energy path and give properties of the crystallization path. In this confined system, depletion effects, which could also be caused by slow material transport in the solution, prevent the post-critical cluster from further growth, and the crystalline state would only be stable at larger cluster sizes. Fluctuation of the higher coupling strength of the crystalline state enables further growth until the crystalline cluster is in equilibrium with the solvent, and this way, a second barrier is crossed. From the parameters and setup, we find necessary conditions for the occurrence of two-step nucleation in our system. These findings can be adapted to real systems as biomineralization, colloidal crystallization, and the solidification of metals.
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Affiliation(s)
- Jacob Holder
- Department of Physics, University of Konstanz, 78464 Konstanz, Germany
| | - Ralf Schmid
- Department of Physics, University of Konstanz, 78464 Konstanz, Germany
| | - Peter Nielaba
- Department of Physics, University of Konstanz, 78464 Konstanz, Germany
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22
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Condensation and Crystal Nucleation in a Lattice Gas with a Realistic Phase Diagram. ENTROPY 2022; 24:e24030419. [PMID: 35327929 PMCID: PMC8953323 DOI: 10.3390/e24030419] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/20/2022] [Revised: 03/15/2022] [Accepted: 03/15/2022] [Indexed: 11/17/2022]
Abstract
We reconsider model II of Orban et al. (J. Chem. Phys. 1968, 49, 1778−1783), a two-dimensional lattice-gas system featuring a crystalline phase and two distinct fluid phases (liquid and vapor). In this system, a particle prevents other particles from occupying sites up to third neighbors on the square lattice, while attracting (with decreasing strength) particles sitting at fourth- or fifth-neighbor sites. To make the model more realistic, we assume a finite repulsion at third-neighbor distance, with the result that a second crystalline phase appears at higher pressures. However, the similarity with real-world substances is only partial: Upon closer inspection, the alleged liquid−vapor transition turns out to be a continuous (albeit sharp) crossover, even near the putative triple point. Closer to the standard picture is instead the freezing transition, as we show by computing the free-energy barrier relative to crystal nucleation from the “liquid”.
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23
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Unsupervised topological learning approach of crystal nucleation. Sci Rep 2022; 12:3195. [PMID: 35210485 PMCID: PMC8873400 DOI: 10.1038/s41598-022-06963-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Accepted: 01/27/2022] [Indexed: 12/12/2022] Open
Abstract
Nucleation phenomena commonly observed in our every day life are of fundamental, technological and societal importance in many areas, but some of their most intimate mechanisms remain however to be unravelled. Crystal nucleation, the early stages where the liquid-to-solid transition occurs upon undercooling, initiates at the atomic level on nanometre length and sub-picoseconds time scales and involves complex multidimensional mechanisms with local symmetry breaking that can hardly be observed experimentally in the very details. To reveal their structural features in simulations without a priori, an unsupervised learning approach founded on topological descriptors loaned from persistent homology concepts is proposed. Applied here to monatomic metals, it shows that both translational and orientational ordering always come into play simultaneously as a result of the strong bonding when homogeneous nucleation starts in regions with low five-fold symmetry. It also reveals the specificity of the nucleation pathways depending on the element considered, with features beyond the hypothesis of Classical Nucleation Theory.
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24
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Kawak P, Banks DS, Tree DR. Semiflexible oligomers crystallize via a cooperative phase transition. J Chem Phys 2021; 155:214902. [PMID: 34879681 DOI: 10.1063/5.0067788] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Semicrystalline polymers are ubiquitous, yet despite their fundamental and industrial importance, the theory of homogeneous nucleation from a melt remains a subject of debate. A key component of the controversy is that polymer crystallization is a non-equilibrium process, making it difficult to distinguish between effects that are purely kinetic and those that arise from the underlying thermodynamics. Due to computational cost constraints, simulations of polymer crystallization typically employ non-equilibrium molecular dynamics techniques with large degrees of undercooling that further exacerbate the coupling between thermodynamics and kinetics. In a departure from this approach, in this study, we isolate the near-equilibrium nucleation behavior of a simple model of a melt of short, semiflexible oligomers. We employ several Monte Carlo methods and compute a phase diagram in the temperature-density plane along with two-dimensional free energy landscapes (FELs) that characterize the nucleation behavior. The phase diagram shows the existence of ordered nematic and crystalline phases in addition to the disordered melt phase. The minimum free energy path in the FEL for the melt-crystal transition shows a cooperative transition, where nematic order and monomer positional order move in tandem as the system crystallizes. This near-equilibrium phase transition mechanism broadly agrees with recent evidence that polymer stiffness plays an important role in crystallization but differs in the specifics of the mechanism from several recent theories. We conclude that the computation of multidimensional FELs for models that are larger and more fine-grained will be important for evaluating and refining theories of homogeneous nucleation for polymer crystallization.
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Affiliation(s)
- Pierre Kawak
- Department of Chemical Engineering, Brigham Young University, Provo, Utah 84602, USA
| | - Dakota S Banks
- Department of Chemical Engineering, Brigham Young University, Provo, Utah 84602, USA
| | - Douglas R Tree
- Department of Chemical Engineering, Brigham Young University, Provo, Utah 84602, USA
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25
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Schwarz J, Leiderer P, Palberg T. Salt-concentration-dependent nucleation rates in low-metastability colloidal charged sphere melts containing small amounts of doublets. Phys Rev E 2021; 104:064607. [PMID: 35030906 DOI: 10.1103/physreve.104.064607] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Accepted: 11/29/2021] [Indexed: 06/14/2023]
Abstract
We determined bulk crystal nucleation rates in aqueous suspensions of charged spheres at low metastability. Experiments were performed in dependence on electrolyte concentration and for two different particle number densities. The time-dependent nucleation rate shows a pronounced initial peak, while postsolidification crystal size distributions are skewed towards larger crystallite sizes. At each concentration, the nucleation rate density initially drops exponentially with increasing salt concentration. The full data set, however, shows an unexpected scaling of the nucleation rate densities with metastability times the number density of particles. Parameterization of our results in terms of classical nucleation theory reveals unusually low interfacial free energies of the nucleus surfaces and nucleation barriers well below the thermal energy. We tentatively attribute our observations to the presence of doublets introduced by the employed conditioning technique. We discuss the conditions under which such small seeds may induce nucleation.
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Affiliation(s)
- J Schwarz
- Institute of Physics, Johannes Gutenberg University, 55128 Mainz, Germany
| | - P Leiderer
- Fachbereicht Physik, University of Konstanz, 78457 Konstanz, Germany
| | - T Palberg
- Institute of Physics, Johannes Gutenberg University, 55128 Mainz, Germany
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26
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Gao Q, Ai J, Tang S, Li M, Chen Y, Huang J, Tong H, Xu L, Xu L, Tanaka H, Tan P. Fast crystal growth at ultra-low temperatures. NATURE MATERIALS 2021; 20:1431-1439. [PMID: 33958770 DOI: 10.1038/s41563-021-00993-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Accepted: 03/22/2021] [Indexed: 06/12/2023]
Abstract
It is believed that the slow liquid diffusion and geometric frustration brought by a rapid, deep quench inhibit fast crystallization and promote vitrification. Here we report fast crystal growth in charged colloidal systems under deep supercooling, where liquid diffusion is extremely low. By combining experiments and simulations, we show that this process occurs via wall-induced barrierless ordering consisting of two coupled steps: the step-like advancement of the rough interface that disintegrates frustration, followed by defect repairing inside the newly formed solid phase. The former is a diffusionless collective process, whereas the latter controls crystal quality. We further show that the intrinsic mechanical instability of a disordered glassy state subject to the crystal growth front allows for domino-like fast crystal growth even at ultra-low temperatures. These findings contribute to a deeper understanding of fast crystal growth and may be useful for applications related to vitrification prevention and crystal-quality control.
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Affiliation(s)
- Qiong Gao
- State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai, China
| | - Jingdong Ai
- International Centre for Quantum Materials and School of Physics, Peking University, Beijing, China
| | - Shixiang Tang
- State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai, China
| | - Minhuan Li
- State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai, China
| | - Yanshuang Chen
- State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai, China
| | - Jiping Huang
- State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai, China
| | - Hua Tong
- Department of Fundamental Engineering, Institute of Industrial Science, University of Tokyo, Tokyo, Japan
- School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai, China
- Department of Physics, University of Science and Technology of China, Hefei, China
| | - Lei Xu
- Department of Physics, The Chinese University of Hong Kong, Hong Kong, China
| | - Limei Xu
- International Centre for Quantum Materials and School of Physics, Peking University, Beijing, China.
- Collaborative Innovation Center of Quantum Matter, Beijing, China.
| | - Hajime Tanaka
- Department of Fundamental Engineering, Institute of Industrial Science, University of Tokyo, Tokyo, Japan.
- Research Center for Advanced Science and Technology, University of Tokyo, Tokyo, Japan.
| | - Peng Tan
- State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai, China.
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27
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Persch C, Müller MJ, Yadav A, Pries J, Honné N, Kerres P, Wei S, Tanaka H, Fantini P, Varesi E, Pellizzer F, Wuttig M. The potential of chemical bonding to design crystallization and vitrification kinetics. Nat Commun 2021; 12:4978. [PMID: 34404800 PMCID: PMC8371141 DOI: 10.1038/s41467-021-25258-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Accepted: 07/29/2021] [Indexed: 11/05/2022] Open
Abstract
Controlling a state of material between its crystalline and glassy phase has fostered many real-world applications. Nevertheless, design rules for crystallization and vitrification kinetics still lack predictive power. Here, we identify stoichiometry trends for these processes in phase change materials, i.e. along the GeTe-GeSe, GeTe-SnTe, and GeTe-Sb2Te3 pseudo-binary lines employing a pump-probe laser setup and calorimetry. We discover a clear stoichiometry dependence of crystallization speed along a line connecting regions characterized by two fundamental bonding types, metallic and covalent bonding. Increasing covalency slows down crystallization by six orders of magnitude and promotes vitrification. The stoichiometry dependence is correlated with material properties, such as the optical properties of the crystalline phase and a bond indicator, the number of electrons shared between adjacent atoms. A quantum-chemical map explains these trends and provides a blueprint to design crystallization kinetics. Tailoring the crystallization kinetics of materials is important for targeting applications. Here the authors observe a remarkable dependence of crystallization and vitrification kinetics and attribute it to systematic bonding changes for a class of materials between metallic and covalent bonding.
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Affiliation(s)
- Christoph Persch
- I. Institute of Physics, Physics of Novel Materials, RWTH Aachen University, Aachen, Germany
| | - Maximilian J Müller
- I. Institute of Physics, Physics of Novel Materials, RWTH Aachen University, Aachen, Germany
| | - Aakash Yadav
- I. Institute of Physics, Physics of Novel Materials, RWTH Aachen University, Aachen, Germany
| | - Julian Pries
- I. Institute of Physics, Physics of Novel Materials, RWTH Aachen University, Aachen, Germany
| | - Natalie Honné
- I. Institute of Physics, Physics of Novel Materials, RWTH Aachen University, Aachen, Germany
| | - Peter Kerres
- I. Institute of Physics, Physics of Novel Materials, RWTH Aachen University, Aachen, Germany
| | - Shuai Wei
- I. Institute of Physics, Physics of Novel Materials, RWTH Aachen University, Aachen, Germany.,Department of Chemistry, Aarhus University, Aarhus C, Denmark
| | - Hajime Tanaka
- Institute of Industrial Science, University of Tokyo, Meguro-ku, Tokyo, Japan.,Research Center for Advanced Science and Technology, University of Tokyo, Meguro-ku, Tokyo, Japan
| | | | | | | | - Matthias Wuttig
- I. Institute of Physics, Physics of Novel Materials, RWTH Aachen University, Aachen, Germany. .,Jülich-Aachen Research Alliance (JARA FIT and JARA HPC), RWTH Aachen University, Aachen, Germany. .,PGI 10 (Green IT), Forschungszentrum Jülich GmbH, Jülich, Germany.
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28
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Posey AE, Ruff KM, Lalmansingh JM, Kandola TS, Lange JJ, Halfmann R, Pappu RV. Mechanistic Inferences From Analysis of Measurements of Protein Phase Transitions in Live Cells. J Mol Biol 2021; 433:166848. [PMID: 33539877 PMCID: PMC8561728 DOI: 10.1016/j.jmb.2021.166848] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Revised: 01/10/2021] [Accepted: 01/25/2021] [Indexed: 02/07/2023]
Abstract
The combination of phase separation and disorder-to-order transitions can give rise to ordered, semi-crystalline fibrillar assemblies that underlie prion phenomena namely, the non-Mendelian transfer of information across cells. Recently, a method known as Distributed Amphifluoric Förster Resonance Energy Transfer (DAmFRET) was developed to study the convolution of phase separation and disorder-to-order transitions in live cells. In this assay, a protein of interest is expressed to a broad range of concentrations and the acquisition of local density and order, measured by changes in FRET, is used to map phase transitions for different proteins. The high-throughput nature of this assay affords the promise of uncovering sequence-to-phase behavior relationships in live cells. Here, we report the development of a supervised method to obtain automated and accurate classifications of phase transitions quantified using the DAmFRET assay. Systems that we classify as undergoing two-state discontinuous transitions are consistent with prion-like behaviors, although the converse is not always true. We uncover well-established and surprising new sequence features that contribute to two-state phase behavior of prion-like domains. Additionally, our method enables quantitative, comparative assessments of sequence-specific driving forces for phase transitions in live cells. Finally, we demonstrate that a modest augmentation of DAmFRET measurements, specifically time-dependent protein expression profiles, can allow one to apply classical nucleation theory to extract sequence-specific lower bounds on the probability of nucleating ordered assemblies. Taken together, our approaches lead to a useful analysis pipeline that enables the extraction of mechanistic inferences regarding phase transitions in live cells.
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Affiliation(s)
- Ammon E Posey
- Department of Biomedical Engineering and Center for Science & Engineering of Living Systems, Washington University in St. Louis, St. Louis, MO 63130, USA.
| | - Kiersten M Ruff
- Department of Biomedical Engineering and Center for Science & Engineering of Living Systems, Washington University in St. Louis, St. Louis, MO 63130, USA
| | - Jared M Lalmansingh
- Department of Biomedical Engineering and Center for Science & Engineering of Living Systems, Washington University in St. Louis, St. Louis, MO 63130, USA; Department of Physics, Washington University in St. Louis, St. Louis, MO 63130, USA
| | - Tejbir S Kandola
- Stowers Institute for Medical Research, Kansas City, MO 64110, USA; The Open University, Milton Keynes MK7 6AA, United Kingdom
| | - Jeffrey J Lange
- Stowers Institute for Medical Research, Kansas City, MO 64110, USA
| | - Randal Halfmann
- Stowers Institute for Medical Research, Kansas City, MO 64110, USA; Department of Molecular and Integrative Physiology, University of Kansas Medical Center, Kansas City, KS 66160, USA
| | - Rohit V Pappu
- Department of Biomedical Engineering and Center for Science & Engineering of Living Systems, Washington University in St. Louis, St. Louis, MO 63130, USA.
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29
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A New Atomistic Mechanism for Heterogeneous Nucleation in the Systems with Negative Lattice Misfit: Creating a 2D Template for Crystal Growth. METALS 2021. [DOI: 10.3390/met11030478] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Heterogeneous nucleation is a widespread phenomenon in both nature and technology. However, our current understanding is largely confined to the classical nucleation theory (CNT) postulated over a century ago, in which heterogeneous nucleation occurs stochastically to form a spherical cap facilitated by a substrate. In this paper, we show that heterogeneous nucleation in systems with negative lattice misfit completes deterministically within three atomic layers by structural templating to form a two-dimentional template from which the new phase can grow. Using molecular dynamics (MD) simulations of a generic system containing metallic liquid (Al) and a substrate of variable lattice misfit (fcc lattice with fixed Al atoms), we found that heterogeneous nucleation proceeds layer-by-layer: the first layer accommodates misfit through a partial edge dislocation network; the second layer twists an angle through a partial screw dislocation network to reduce lattice distortion; and the third layer creates a crystal plane of the solid (the 2D nucleus) that templates further growth. The twist angle of the solid relative to the substrate as a signature of heterogeneous nucleation in the systems with negative lattice misfit has been validated by high resolution transmission electron microscopic (HRTEM) examination of TiB2/Al and TiB2/α-Al15(Fe, Mn)3Si2 interfaces in two different Al-alloys.
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30
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Goswami A, Singh JK. Homogeneous nucleation of sheared liquids: advances and insights from simulations and theory. Phys Chem Chem Phys 2021; 23:15402-15419. [PMID: 34279013 DOI: 10.1039/d1cp02617h] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
One of the most ubiquitous and technologically important phenomena in nature is the nucleation of homogeneous flowing systems. The microscopic effects of shear on a nucleating system are still imperfectly understood, although in recent years a consistent picture has emerged. The opposing effects of shear can be split into two major contributions for simple atomic and molecular liquids: increase of the energetic cost of nucleation, and enhancement of the kinetics. In this perspective, we describe the latest computational and theoretical techniques which have been developed over the past two decades. We collate and unify the overarching influences of shear, temperature, and supersaturation on the process of homogeneous nucleation. Experimental techniques and capabilities are discussed, against the backdrop of results from simulations and theory. Although we primarily focus on simple systems, we also touch upon the sheared nucleation of more complex systems, including glasses and polymer melts. We speculate on the promising directions and possible advances that could come to fruition in the future.
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Affiliation(s)
- Amrita Goswami
- Department of Chemical Engineering, Indian Institute of Technology Kanpur, Uttar Pradesh 208016, India.
| | - Jayant K Singh
- Department of Chemical Engineering, Indian Institute of Technology Kanpur, Uttar Pradesh 208016, India.
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31
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Nada H. Melt crystallization mechanism analyzed with dimensional reduction of high-dimensional data representing distribution function geometries. Sci Rep 2020; 10:15465. [PMID: 32963268 PMCID: PMC7508891 DOI: 10.1038/s41598-020-72455-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Accepted: 09/02/2020] [Indexed: 11/21/2022] Open
Abstract
Melt crystallization is essential to many industrial processes, including semiconductor, ice, and food manufacturing. Nevertheless, our understanding of the melt crystallization mechanism remains poor. This is because the molecular-scale structures of melts are difficult to clarify experimentally. Computer simulations, such as molecular dynamics (MD), are often used to investigate melt structures. However, the time evolution of the structural order in a melt during crystallization must be analyzed properly. In this study, dimensional reduction (DR), which is an unsupervised machine learning technique, is used to evaluate the time evolution of structural order. The DR is performed for high-dimensional data representing an atom–atom pair distribution function and the distribution function of the angle formed by three nearest neighboring atoms at each period during crystallization, which are obtained by an MD simulation of a supercooled Lennard–Jones melt. The results indicate that crystallization occurs via the following activation processes: nucleation of a crystal with a distorted structure and reconstruction of the crystal to a more stable structure. The time evolution of the local structures during crystallization is also evaluated with this method. The present method can be applied to studies of the mechanism of crystallization from a disordered system for real materials, even for complicated multicomponent materials.
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32
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Kirova EM, Pisarev VV. Morphological aspect of crystal nucleation in wall-confined supercooled metallic film. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2020; 33:034003. [PMID: 33078713 DOI: 10.1088/1361-648x/abba6b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Accepted: 09/21/2020] [Indexed: 06/11/2023]
Abstract
In this paper, we simulate the nucleation and growth of crystalline nuclei in a molybdenum film cooled at different rates confined between two amorphous walls. We also compare the results for the wall-confined and wall-free systems. We apply the same methodology as in the work (Kirova and Pisarev 2019J. Cryst. Growth528125266) which is based on reconstructing the probability density function for the largest crystalline nucleus in the system. The size of the nucleus and the asphericity parameter are considered as the reaction coordinates. We demonstrate that in both the free and confined systems there are two mechanisms of crystal growth: the attachment of atoms to the biggest crystal from the amorphous phase and the merging of the biggest crystal cluster with small ones (coalescence). We show that the attachment mechanism is dominant in the melt cooled down at a slower rate, and the mechanism gradually shifts to coalescence as cooling rate increases. We also observe the formation of long-lived crystal clusters and demonstrate that amorphous walls do not affect their geometric characteristics. However, system confined between walls demonstrates higher glass-forming ability.
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Affiliation(s)
- E M Kirova
- National Research University Higher School of Economics, 20 Myasnitskaya str., 101000 Moscow, Russia
- Joint Institute for High Temperatures of RAS, 13/2 Izhorskaya str., 125412 Moscow, Russia
| | - V V Pisarev
- National Research University Higher School of Economics, 20 Myasnitskaya str., 101000 Moscow, Russia
- Joint Institute for High Temperatures of RAS, 13/2 Izhorskaya str., 125412 Moscow, Russia
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33
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Affiliation(s)
- Hajime Tanaka
- Department of Fundamental Engineering, Institute of Industrial Science, University of Tokyo, Meguro-ku, Tokyo 153-8505, Japan
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34
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Lehmkühler F, Hankiewicz B, Schroer MA, Müller L, Ruta B, Sheyfer D, Sprung M, Tono K, Katayama T, Yabashi M, Ishikawa T, Gutt C, Grübel G. Slowing down of dynamics and orientational order preceding crystallization in hard-sphere systems. SCIENCE ADVANCES 2020; 6:6/43/eabc5916. [PMID: 33087351 PMCID: PMC7577711 DOI: 10.1126/sciadv.abc5916] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2020] [Accepted: 09/04/2020] [Indexed: 05/27/2023]
Abstract
Despite intensive studies in the past decades, the local structure of disordered matter remains widely unknown. We show the results of a coherent x-ray scattering study revealing higher-order correlations in dense colloidal hard-sphere systems in the vicinity of their crystallization and glass transition. With increasing volume fraction, we observe a strong increase in correlations at both medium-range and next-neighbor distances in the supercooled state, both invisible to conventional scattering techniques. Next-neighbor correlations are indicative of ordered precursor clusters preceding crystallization. Furthermore, the increase in such correlations is accompanied by a marked slowing down of the dynamics, proving experimentally a direct relation between orientational order and sample dynamics in a soft matter system. In contrast, correlations continuously increase for nonequilibrated, glassy samples, suggesting that orientational order is reached before the sample slows down to reach (quasi-)equilibrium.
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Affiliation(s)
- Felix Lehmkühler
- Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany.
- The Hamburg Centre for Ultrafast Imaging, Luruper Chaussee 149, 22761 Hamburg, Germany
| | - Birgit Hankiewicz
- Institute of Physical Chemistry, Hamburg University, Grindelallee 117, 20146 Hamburg, Germany
| | - Martin A Schroer
- European Molecular Biology Laboratory (EMBL), Hamburg Outstation c/o DESY, Notkestr. 85, 22607 Hamburg, Germany
| | - Leonard Müller
- Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany
| | - Beatrice Ruta
- Université de Lyon, Université Claude Bernard Lyon 1, CNRS, Institut Lumière Matière, 69622 Villeurbanne, France
- ESRF-The European Synchrotron, 38043 Grenoble cedex, France
| | - Dina Sheyfer
- Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany
- The Hamburg Centre for Ultrafast Imaging, Luruper Chaussee 149, 22761 Hamburg, Germany
| | - Michael Sprung
- Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany
| | - Kensuke Tono
- Japan Synchrotron Radiation Research Institute, 1-1-1 Kuoto, Sayo-cho, Sayo-gun, Hyogo 679-5198, Japan
| | - Tetsuo Katayama
- Japan Synchrotron Radiation Research Institute, 1-1-1 Kuoto, Sayo-cho, Sayo-gun, Hyogo 679-5198, Japan
- RIKEN SPring-8 Center, 1-1-1 Kuoto, Sayo-cho, Sayo-gun, Hyogo 679-5148, Japan
| | - Makina Yabashi
- Japan Synchrotron Radiation Research Institute, 1-1-1 Kuoto, Sayo-cho, Sayo-gun, Hyogo 679-5198, Japan
- RIKEN SPring-8 Center, 1-1-1 Kuoto, Sayo-cho, Sayo-gun, Hyogo 679-5148, Japan
| | - Tetsuya Ishikawa
- RIKEN SPring-8 Center, 1-1-1 Kuoto, Sayo-cho, Sayo-gun, Hyogo 679-5148, Japan
| | - Christian Gutt
- Department of Physics, University of Siegen, Walter-Flex-Str. 3, 57072 Siegen, Germany
| | - Gerhard Grübel
- Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany
- The Hamburg Centre for Ultrafast Imaging, Luruper Chaussee 149, 22761 Hamburg, Germany
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35
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Menon S, Díaz Leines G, Drautz R, Rogal J. Role of pre-ordered liquid in the selection mechanism of crystal polymorphs during nucleation. J Chem Phys 2020; 153:104508. [DOI: 10.1063/5.0017575] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Sarath Menon
- Interdisciplinary Centre for Advanced Materials Simulation, Ruhr-Universität Bochum, 44801 Bochum, Germany
| | - Grisell Díaz Leines
- Interdisciplinary Centre for Advanced Materials Simulation, Ruhr-Universität Bochum, 44801 Bochum, Germany
| | - Ralf Drautz
- Interdisciplinary Centre for Advanced Materials Simulation, Ruhr-Universität Bochum, 44801 Bochum, Germany
| | - Jutta Rogal
- Interdisciplinary Centre for Advanced Materials Simulation, Ruhr-Universität Bochum, 44801 Bochum, Germany
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36
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Li M, Chen Y, Tanaka H, Tan P. Revealing roles of competing local structural orderings in crystallization of polymorphic systems. SCIENCE ADVANCES 2020; 6:eaaw8938. [PMID: 32656336 PMCID: PMC7329355 DOI: 10.1126/sciadv.aaw8938] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2019] [Accepted: 05/15/2020] [Indexed: 05/27/2023]
Abstract
Most systems have more than two stable crystalline states in the phase diagram, which is known as polymorphism. Crystallization in such a system is often under strong influence of competing orderings linked to those crystals. However, how such competition affects crystal nucleation and ordering toward the final crystalline state is largely unknown. This is primarily because the competition takes place locally and thus is masked by large positional fluctuations. We develop a unique method to correctly identify local symmetries by removing their distortions due to positional fluctuations. This allows us to experimentally access the spatiotemporal fluctuations of local symmetries at a single-particle level in crystallization of a charged colloidal system near the body-centered cubic-face-centered cubic border. Thus, we successfully reveal the crucial roles of competing ordering in the initial selection of polymorphs and the final grain boundary motion toward the most stable state from a microscopic perspective.
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Affiliation(s)
- Minhuan Li
- State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai 200433, China
| | - Yanshuang Chen
- State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai 200433, China
| | - Hajime Tanaka
- Department of Fundamental Engineering, Institute of Industrial Science, University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8505, Japan
| | - Peng Tan
- State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai 200433, China
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37
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Liang Y, Díaz Leines G, Drautz R, Rogal J. Identification of a multi-dimensional reaction coordinate for crystal nucleation in Ni3Al. J Chem Phys 2020; 152:224504. [DOI: 10.1063/5.0010074] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Affiliation(s)
- Yanyan Liang
- Interdisciplinary Centre for Advanced Materials Simulation, Ruhr-Universität Bochum, 44780 Bochum, Germany
| | - Grisell Díaz Leines
- Interdisciplinary Centre for Advanced Materials Simulation, Ruhr-Universität Bochum, 44780 Bochum, Germany
| | - Ralf Drautz
- Interdisciplinary Centre for Advanced Materials Simulation, Ruhr-Universität Bochum, 44780 Bochum, Germany
| | - Jutta Rogal
- Interdisciplinary Centre for Advanced Materials Simulation, Ruhr-Universität Bochum, 44780 Bochum, Germany
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38
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Ouyang W, Sun B, Sun Z, Xu S. Entire crystallization process of Lennard-Jones liquids: A large-scale molecular dynamics study. J Chem Phys 2020; 152:054903. [DOI: 10.1063/1.5139574] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Affiliation(s)
- Wenze Ouyang
- Key Laboratory of Microgravity (National Microgravity Laboratory), Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190, China
| | - Bin Sun
- School of Materials and Chemical Engineering, Zhongyuan University of Technology, Zhengzhou 450007, China
| | - Zhiwei Sun
- Key Laboratory of Microgravity (National Microgravity Laboratory), Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190, China
| | - Shenghua Xu
- Key Laboratory of Microgravity (National Microgravity Laboratory), Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190, China
- School of Engineering Science, University of Chinese Academy of Sciences, Beijing 100049, China
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39
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Seo B, Ha MY, Yu JW, Lee WB. Enhanced sampling of cylindrical microphase separation via a shell-averaged bond-orientational order parameter. SOFT MATTER 2020; 16:659-667. [PMID: 31803899 DOI: 10.1039/c9sm01603a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The formation of a hexagonal phase from disordered phase is one of the typical order-disorder transitions (ODTs) observed in asymmetric diblock copolymer systems. In order to drive this transition in a particle-based simulation, we introduce a shell-based bond-orientational order parameter that selectively responds to the mesoscopic order of the hexagonal cylinder phase. From metadynamics simulations in a bond-free particle model system, the characteristic pathway involved with the underlying free energy surface is deduced for the disordered-to-hexagonal transition. It is shown consecutively that the transition pathway and the metastable state are reproduced in dissipative particle dynamics simulations for the corresponding transition in a bulk asymmetric block copolymer melt system. These agreements suggest that efficient strategies for enhanced sampling with particle-based simulations of block copolymer systems can be devised using coarse-grained pictures of the mesoscopic order.
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Affiliation(s)
- Bumjoon Seo
- School of Chemical and Biological Engineering, Institute of Chemical Processes, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea.
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40
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Tateno M, Yanagishima T, Russo J, Tanaka H. Influence of Hydrodynamic Interactions on Colloidal Crystallization. PHYSICAL REVIEW LETTERS 2019; 123:258002. [PMID: 31922768 DOI: 10.1103/physrevlett.123.258002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Indexed: 06/10/2023]
Abstract
One of the biggest unresolved problems in crystallization phenomena is the significant discrepancy in the nucleation rate between experiments and simulations even for the simplest liquid, i.e., the hard-sphere system. A popular explanation for this discrepancy is the neglect of hydrodynamic interactions (HI) in simulation studies. By comparing simulations with and without HI, we show that the long-time diffusive dynamics of the colloids is slowed down more rapidly by hydrodynamic lubrication effects with increasing volume fraction. We find that the kinetics of both nucleation and growth are controlled by this long-time diffusion and that it is possible to account for most of the effects of HI by rescaling with this timescale. Therefore, we conclude that HI is not the primary cause of the accelerated nucleation rates observed in experiments.
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Affiliation(s)
- Michio Tateno
- Department of Fundamental Engineering, Institute of Industrial Science, University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8505, Japan
| | - Taiki Yanagishima
- Department of Chemistry, University of Oxford, Oxford OX1 3QZ, United Kingdom
| | - John Russo
- Department of Physics, Sapienza University, P.le Aldo Moro 5, 00185 Rome, Italy
| | - Hajime Tanaka
- Department of Fundamental Engineering, Institute of Industrial Science, University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8505, Japan
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41
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Shao M, Zhang C, Qi C, Wang C, Wang J, Ye F, Zhou X. Hydrogen polarity of interfacial water regulates heterogeneous ice nucleation. Phys Chem Chem Phys 2019; 22:258-264. [PMID: 31808477 DOI: 10.1039/c9cp04867g] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Using all-atomic molecular dynamics (MD) simulations, we show that the structure of interfacial water (IW) induced by substrates characterizes the ability of a substrate to nucleate ice. We probe the shape and structure of ice nuclei and the corresponding supercooling temperatures to measure the ability of IW with various hydrogen polarities for ice nucleation, and find that the hydrogen polarization of IW even with the ice-like oxygen lattice increases the contact angle of the ice nucleus on IW, thus lifting the free energy barrier of heterogeneous ice nucleation. The results show that not only the oxygen lattice order but the hydrogen disorder of IW on substrates are required to effectively facilitate the freezing of top water.
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Affiliation(s)
- Mingzhe Shao
- College of Light Industry Science and Engineering, Tianjin University of Science and Technology, Tianjin, China
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42
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Drastic enhancement of crystal nucleation in a molecular liquid by its liquid-liquid transition. Proc Natl Acad Sci U S A 2019; 116:24949-24955. [PMID: 31767771 DOI: 10.1073/pnas.1909660116] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Crystallization is one of the most familiar and fundamental phase transition phenomena. There is a possibility that crystallization may be enhanced by critical-like fluctuations associated with another nearby phase transition if the order parameter of the former is coupled to that of the latter; however, the mechanism of such order parameter coupling and its generality remain elusive due to the lack of experimental studies. Here we report experimental evidence for a nontrivial coupling between crystallization and liquid-liquid transition (LLT) for a molecular liquid, triphenyl phosphite. We find that the crystal nucleation frequency is drastically enhanced by short-time preannealing near but above the spinodal temperature of LLT. By successfully separating the thermodynamic and kinetic factors governing crystal nucleation, we show that this enhancement is induced by the lowering of the crystal-liquid interfacial energy due to the presence of critical-like order parameter fluctuations. This finding may be regarded as a fingerprint of the presence of LLT below the melting point. Thus, it may allow us not only to control the crystal nucleation frequency by LLT but also to unveil LLT hidden behind crystallization. This enhancement of nucleation frequency by critical-like fluctuations of another ordering phenomenon may be general to a variety of combinations of phase transitions. It would provide a way to control a crystal grain structure, which is a crucial control factor of mechanical and thermal properties of crystalline materials.
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43
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Adorf CS, Moore TC, Melle YJU, Glotzer SC. Analysis of Self-Assembly Pathways with Unsupervised Machine Learning Algorithms. J Phys Chem B 2019; 124:69-78. [DOI: 10.1021/acs.jpcb.9b09621] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Carl S. Adorf
- Department of Chemical Engineering, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Timothy C. Moore
- Department of Chemical Engineering, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Yannah J. U. Melle
- Department of Chemical Engineering, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Sharon C. Glotzer
- Department of Chemical Engineering, University of Michigan, Ann Arbor, Michigan 48109, United States
- Department of Materials Science and Engineering, University of Michigan, Ann Arbor, Michigan 48109, United States
- Biointerfaces Institute, University of Michigan, Ann Arbor, Michigan 48109, United States
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44
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Leoni F, Shi R, Tanaka H, Russo J. Crystalline clusters in mW water: Stability, growth, and grain boundaries. J Chem Phys 2019; 151:044505. [DOI: 10.1063/1.5100812] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Fabio Leoni
- School of Mathematics, University of Bristol, Bristol BS8 1TW, United Kingdom
| | - Rui Shi
- Department of Fundamental Engineering, Institute of Industrial Science, University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8505, Japan
| | - Hajime Tanaka
- Department of Fundamental Engineering, Institute of Industrial Science, University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8505, Japan
| | - John Russo
- School of Mathematics, University of Bristol, Bristol BS8 1TW, United Kingdom
- Department of Fundamental Engineering, Institute of Industrial Science, University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8505, Japan
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45
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Shi R, Tanaka H. Homogeneous nucleation of ferroelectric ice crystal driven by spontaneous dipolar ordering in supercooled TIP5P water. J Chem Phys 2019; 151:024501. [DOI: 10.1063/1.5100634] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Rui Shi
- Department of Fundamental Engineering, Institute of Industrial Science, University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8505, Japan
| | - Hajime Tanaka
- Department of Fundamental Engineering, Institute of Industrial Science, University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8505, Japan
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46
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Hall KW, Sirk TW, Klein ML, Shinoda W. A coarse-grain model for entangled polyethylene melts and polyethylene crystallization. J Chem Phys 2019; 150:244901. [PMID: 31255065 DOI: 10.1063/1.5092229] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
The Shinoda-DeVane-Klein (SDK) model is herein demonstrated to be a viable coarse-grain model for performing molecular simulations of polyethylene (PE), affording new opportunities to advance molecular-level, scientific understanding of PE materials and processes. Both structural and dynamical properties of entangled PE melts are captured by the SDK model, which also recovers important aspects of PE crystallization phenomenology. Importantly, the SDK model can be used to represent a variety of materials beyond PE and has a simple functional form, making it unique among coarse-grain PE models. This study expands the suite of tools for studying PE in silico and paves the way for future work probing PE and PE-based composites at the molecular level.
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Affiliation(s)
- Kyle Wm Hall
- Department of Materials Chemistry, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan
| | - Timothy W Sirk
- U.S. Army Research Laboratory, Aberdeen Proving Ground, Maryland 21005, USA
| | - Michael L Klein
- Department of Chemistry, Temple University, Philadelphia, Pennsylvania 19122, USA
| | - Wataru Shinoda
- Department of Materials Chemistry, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan
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47
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Qiao Z, Zhao Y, Gao YQ. Ice Nucleation of Confined Monolayer Water Conforms to Classical Nucleation Theory. J Phys Chem Lett 2019; 10:3115-3121. [PMID: 31117689 DOI: 10.1021/acs.jpclett.9b01169] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
We confirmed that monolayer water confined by parallel graphene sheets spontaneously crystallizes from a structurally and dynamically heterogeneous liquid phase under moderate supercooling via direct molecular dynamics simulation. Square-lattice-like geometric order is observed at the early stage of nucleation and is preserved during the entire nucleus growth process. The diffusion coefficient and free energy profile in the cluster space extracted from a Bayesian trajectory analysis agree well with the classical nucleation theory (CNT) prediction and yield thermodynamic quantities exhibiting linear temperature dependence. The effectiveness of maximum cluster size as the descriptor of ice nucleation dynamics in the CNT framework can be attributed to the dynamical time scale decoupling and strong structural pattern dependence of density fluctuation in the liquid phase.
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Affiliation(s)
- Zhuoran Qiao
- Institute of Theoretical and Computational Chemistry, College of Chemistry and Molecular Engineering, Peking National Laboratory for Molecular Science , Peking University , Beijing 100871 , China
| | - Yuheng Zhao
- Institute of Theoretical and Computational Chemistry, College of Chemistry and Molecular Engineering, Peking National Laboratory for Molecular Science , Peking University , Beijing 100871 , China
| | - Yi Qin Gao
- Institute of Theoretical and Computational Chemistry, College of Chemistry and Molecular Engineering, Peking National Laboratory for Molecular Science , Peking University , Beijing 100871 , China
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48
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Liang S, Hall KW, Laaksonen A, Zhang Z, Kusalik PG. Characterizing key features in the formation of ice and gas hydrate systems. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2019; 377:20180167. [PMID: 30982452 PMCID: PMC6501917 DOI: 10.1098/rsta.2018.0167] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 02/26/2019] [Indexed: 05/16/2023]
Abstract
Crystallization in liquids is critical to a range of important processes occurring in physics, chemistry and life sciences. In this article, we review our efforts towards understanding the crystallization mechanisms, where we focus on theoretical modelling and molecular simulations applied to ice and gas hydrate systems. We discuss the order parameters used to characterize molecular ordering processes and how different order parameters offer different perspectives of the underlying mechanisms of crystallization. With extensive simulations of water and gas hydrate systems, we have revealed unexpected defective structures and demonstrated their important roles in crystallization processes. Nucleation of gas hydrates can in most cases be characterized to take place in a two-step mechanism where the nucleation occurs via intermediate metastable precursors, which gradually reorganizes to a stable crystalline phase. We have examined the potential energy landscapes explored by systems during nucleation, and have shown that these landscapes are rugged and funnel-shaped. These insights provide a new framework for understanding nucleation phenomena that has not been addressed in classical nucleation theory. This article is part of the theme issue 'The physics and chemistry of ice: scaffolding across scales, from the viability of life to the formation of planets'.
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Affiliation(s)
- Shuai Liang
- Key Laboratory of Gas Hydrate, Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangdong Key Laboratory of New and Renewable Energy Research and Development, Guangzhou, People's Republic of China
| | - Kyle Wm. Hall
- Department of Chemistry, Temple University, Philadelphia, PA, USA
| | - Aatto Laaksonen
- Department of Materials and Environmental Chemistry, Arrhenius Laboratory, Stockholm University, Stockholm, Sweden
- Department of Chemistry-Ångström Laboratory, Uppsala University, 75121 Uppsala, Sweden
- Centre of Advanced Research in Bionanoconjugates and Biopolymers, Petru Poni Institute of Macromolecular Chemistry, Aleea Grigore Ghica-Voda, 41A, 700487 Iasi, Romania
| | - Zhengcai Zhang
- Department of Chemistry, University of Calgary, Calgary, Canada
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49
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Zhang TH, Zhang ZC, Cao JS, Liu XY. Can the pathway of stepwise nucleation be predicted and controlled? Phys Chem Chem Phys 2019; 21:7398-7405. [PMID: 30912550 DOI: 10.1039/c9cp00822e] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Predicting the critical nucleus size and the nucleation barrier is of central importance in controlling the dynamics of nucleation. However, as the nucleation of a crystal involves intermediate states, the prediction becomes inaccessible with currently available models. Here, we show that based on single-particle level observations, the properties of crystal nuclei in a microscopic stepwise nucleation (MSN) can be well-quantified by incorporating the size and structure order parameter into the formula of free energy without prior knowledge of interfacial tension. The quantified free energy reveals that the intermediate structures arise from thermodynamics rather than kinetics. Precritical and postcritical nuclei are distinct not only in structure but also in the mechanism of crystalline ordering. The relative stability of intermediate structures and the pathway of nucleation can be well-controlled by supercooling. Our studies offer a successful approach to quantify MSN and shed new light on resolving the long-standing discrepancies between simulations and experiments.
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Affiliation(s)
- Tian Hui Zhang
- Center for Soft Condensed Matter Physics and Interdisciplinary Research & School of Physical Science and Technology, Soochow University, Suzhou, P. R. China.
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50
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Hall KW, Percec S, Klein ML. Polymer nucleation under high-driving force, long-chain conditions: Heat release and the separation of time scales. J Chem Phys 2019; 150:114901. [PMID: 30902014 DOI: 10.1063/1.5084773] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
This study reveals important features of polymer crystal formation at high-driving forces in entangled polymer melts based on simulations of polyethylene. First and in contrast to small-molecule crystallization, the heat released during polymer crystallization does not appreciably influence structural details of early-stage, crystalline clusters (crystal nuclei). Second, early-stage polymer crystallization (crystal nucleation) can occur without substantial chain-level relaxation and conformational changes. This study's results indicate that local structures and environments guide crystal nucleation in entangled polymer melts under high-driving force conditions. Given that such conditions are often used to process polyethylene, local structures and the separation of time scales associated with crystallization and chain-level processes are anticipated to be of substantial importance to processing strategies. This study highlights new research directions for understanding polymer crystallization.
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Affiliation(s)
- Kyle Wm Hall
- Department of Chemistry, Temple University, Philadelphia, Pennsylvania 19122, USA
| | - Simona Percec
- Department of Chemistry, Temple University, Philadelphia, Pennsylvania 19122, USA
| | - Michael L Klein
- Department of Chemistry, Temple University, Philadelphia, Pennsylvania 19122, USA
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