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Fridrich P, Posel Z. Phase Behavior of Polydisperse Y-Shaped Polymer Brushes under Good Solvent Conditions. Polymers (Basel) 2024; 16:721. [PMID: 38475403 DOI: 10.3390/polym16050721] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2024] [Revised: 02/28/2024] [Accepted: 03/02/2024] [Indexed: 03/14/2024] Open
Abstract
Y-shaped polymer brushes represent a special class of binary mixed polymer brushes, in which a combination of different homopolymers leads to unique phase behavior. While most theoretical and simulation studies use monodisperse models, experimental systems are always polydisperse. This discrepancy hampers linking theoretical and experimental results. In this theoretical study, we employed dissipative particle dynamics to study the influence of polydispersity on the phase behavior of Y-shaped brushes grafted to flat surfaces under good solvent conditions. Polydispersity was kept within experimentally achievable values and was modeled via Schulz-Zimm distribution. In total, 10 systems were considered, thus covering the phase behavior of monodisperse, partially polydisperse and fully polydisperse systems. Using such generic representation of real polymers, we observed a rippled structure and aggregates in monodisperse systems. In addition, polydisperse brushes formed a stable perforated layer not observed previously in monodisperse studies, and influenced the stability of the remaining phases. Although the perforated layer was experimentally observed under good solvent conditions and in the melt state, further confirmation of its presence in systems under good solvent conditions required mapping real polymers onto mesoscale models that reflected, for example, different polymer rigidity, and excluded volume effects or direct influence of the surface, just to mention a few parameters. Finally, in this work, we show that mesoscale modeling successfully describes polydisperse models, which opens the way for rapid exploring of complex systems such as polydisperse Y-shaped brushes in selective or bad solvents or under non-equilibrium conditions.
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Affiliation(s)
- Petr Fridrich
- Department of Informatics, Faculty of Science, Jan Evangelista Purkyně University in Ústí nad Labem, 400 96 Ústí nad Labem, Czech Republic
| | - Zbyšek Posel
- Department of Informatics, Faculty of Science, Jan Evangelista Purkyně University in Ústí nad Labem, 400 96 Ústí nad Labem, Czech Republic
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2
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Šindelka K, Kowalski A, Cooke M, Mendoza C, Lísal M. Interactions of cationic surfactant-fatty alcohol monolayers with natural human hair surface: Insights from dissipative particle dynamics. J Mol Liq 2023. [DOI: 10.1016/j.molliq.2023.121385] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
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3
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Santo KP, Neimark AV. Dissipative particle dynamics simulations in colloid and Interface science: a review. Adv Colloid Interface Sci 2021; 298:102545. [PMID: 34757286 DOI: 10.1016/j.cis.2021.102545] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Revised: 10/07/2021] [Accepted: 10/08/2021] [Indexed: 12/31/2022]
Abstract
Dissipative particle dynamics (DPD) is one of the most efficient mesoscale coarse-grained methodologies for modeling soft matter systems. Here, we comprehensively review the progress in theoretical formulations, parametrization strategies, and applications of DPD over the last two decades. DPD bridges the gap between the microscopic atomistic and macroscopic continuum length and time scales. Numerous efforts have been performed to improve the computational efficiency and to develop advanced versions and modifications of the original DPD framework. The progress in the parametrization techniques that can reproduce the engineering properties of experimental systems attracted a lot of interest from the industrial community longing to use DPD to characterize, help design and optimize the practical products. While there are still areas for improvements, DPD has been efficiently applied to numerous colloidal and interfacial phenomena involving phase separations, self-assembly, and transport in polymeric, surfactant, nanoparticle, and biomolecules systems.
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Affiliation(s)
- Kolattukudy P Santo
- Department of Chemical and Biochemical Engineering, Rutgers, The State University of New Jersey, Piscataway, NJ 08854, United States
| | - Alexander V Neimark
- Department of Chemical and Biochemical Engineering, Rutgers, The State University of New Jersey, Piscataway, NJ 08854, United States.
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4
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Svoboda M, Jiménez S MG, Kowalski A, Cooke M, Mendoza C, Lísal M. Structural properties of cationic surfactant-fatty alcohol bilayers: insights from dissipative particle dynamics. SOFT MATTER 2021; 17:9967-9984. [PMID: 34704992 DOI: 10.1039/d1sm00850a] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Bilayers, self-assembled by cationic surfactants and fatty alcohols in water, are the basic units of lamellar gel networks - creamy formulations extensively used in cosmetics and pharmaceutics. Mesoscopic modelling and study of the bilayers formed by single- or double-tail cationic surfactants (CTAC or DHDAC), and fatty alcohols (FAs) in the lamellar fluid and gel phases were employed. Fatty alcohols with alkyl tail equal to or greater than the surfactant alkyl tail, i.e., C16FA or C18FA and C22FA, were considered. A model formulation was explored with the FA concentration greater than that of the surfactant and the structure of the fluid and gel bilayers in tensionless state characterised via the density profiles across the bilayers, orientational order parameters of the surfactant and FA chains, intrinsic analysis of the bilayer interfaces, and bending rigidity. The intrinsic analysis allows identification and quantification of the coexistence of the interdigitated and non-interdigitated phases present within the gel bilayers. The FA chains were found to conform the primary scaffolding of the bilayers while the surfactant chains tessellate bilayer monolayers from their water-hydrophobic interface. Further, the overlap of the FA chains from the apposed monolayers of the fluid bilayers rises with increasing FA length. Finally, the prevalence of the non-interdigitated phase over the interdigitated phase within the gel bilayers becomes enhanced upon the FA length increase with a preference of the surfactant chains to reside in the non-interdigitated phase rather than the interdigitated phase.
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Affiliation(s)
- Martin Svoboda
- Department of Molecular and Mesoscopic Modelling, The Czech Academy of Sciences, Institute of Chemical Process Fundamentals, Rozvojová 135/1, Prague, Czech Republic.
- Department of Physics, Faculty of Science, Jan Evangelista Purkyně University in Úst nad Labem, Pasteurova 1, Úst nad Labem, Czech Republic
| | | | - Adam Kowalski
- Unilever R&D, Port Sunlight Laboratory, Quarry Road East, Bebington, Wirral CH63 3JW, UK
| | - Michael Cooke
- Unilever R&D, Port Sunlight Laboratory, Quarry Road East, Bebington, Wirral CH63 3JW, UK
| | - César Mendoza
- Unilever R&D, Port Sunlight Laboratory, Quarry Road East, Bebington, Wirral CH63 3JW, UK
| | - Martin Lísal
- Department of Molecular and Mesoscopic Modelling, The Czech Academy of Sciences, Institute of Chemical Process Fundamentals, Rozvojová 135/1, Prague, Czech Republic.
- Department of Physics, Faculty of Science, Jan Evangelista Purkyně University in Úst nad Labem, Pasteurova 1, Úst nad Labem, Czech Republic
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5
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van der Haven DLH, Köhler S, Schreiner E, In 't Veld PJ. Closed-Form Coexistence Equation for Phase Separation of Polymeric Mixtures in Dissipative Particle Dynamics. J Phys Chem B 2021; 125:7485-7498. [PMID: 34196184 DOI: 10.1021/acs.jpcb.0c11274] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
To date, no extensive study of the phase diagram for binary fluid mixtures in dissipative particle dynamics (DPD) has been published. This is especially pertinent for newer parameterization schemes where the self-self interaction, or the effective volume, of different particle types is varied. This work presents an exhaustive study of the parameter space concerning DPD particles with soft interaction potentials. Moreover, we propose a closed-form coexistence equation or binodal curve that is inspired by the Flory-Huggins model. This equation describes the phase diagram of all binary mixtures made up out of monomers, homopolymers, and the mixtures thereof when self-self interactions are varied. The mean absolute percentage error (MAPE) of the equation on simulated data, including validation simulations, is 1.02%. The equation can a priori predict the phase separation of mixtures using only DPD interaction parameters. The proposed coexistence equation can therefore be used to directly validate interaction parameters resulting from novel parameterization schemes, including coarse graining and equations of state, without the need for additional simulations. Finally, it is shown that the choice of bond potential markedly influences phase behavior.
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Affiliation(s)
- Dingeman L H van der Haven
- Department of Chemical Engineering and Chemistry, Eindhoven University of Technology, Eindhoven 5600 MB, The Netherlands
| | - Stephan Köhler
- Polymer Physics, BASF SE, Ludwigshafen am Rhein 67056, Germany
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6
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Driven Transport of Dilute Polymer Solutions through Porous Media Comprising Interconnected Cavities. COLLOIDS AND INTERFACES 2021. [DOI: 10.3390/colloids5020022] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Driven transport of dilute polymer solutions through porous media has been simulated using a recently proposed novel dissipative particle dynamics method satisfying the no-penetration and no-slip boundary conditions. The porous media is an array of overlapping spherical cavities arranged in a simple cubic lattice. Simulations were performed for linear, ring, and star polymers with 12 arms for two cases with the external force acting on (I) both polymer and solvent beads to model a pressure-driven flow; (II) polymer beads only, similar to electrophoresis. When the external force is in the direction of a principal axis, the extent of change in the polymers’ conformation and their alignment with the driving force is more significant for case I. These effects are most pronounced for linear chains, followed by rings and stars at the same molecular weight. Moreover, the polymer mean velocity is affected by its molecular weight and architecture as well as the direction and strength of the imposed force.
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7
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Šindelka K, Lísal M. Interplay between surfactant self-assembly and adsorption at hydrophobic surfaces: insights from dissipative particle dynamics. Mol Phys 2020. [DOI: 10.1080/00268976.2020.1857863] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Affiliation(s)
- Karel Šindelka
- Department of Molecular and Mesoscopic Modelling, The Czech Academy of Sciences, Institute of Chemical Process Fundamentals, Prague, Czech Republic
| | - Martin Lísal
- Department of Molecular and Mesoscopic Modelling, The Czech Academy of Sciences, Institute of Chemical Process Fundamentals, Prague, Czech Republic
- Department of Physics, Faculty of Science, Jan Evangelista Purkyně University in Ústí nad Labem, Ústí nad Labem, Czech Republic
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8
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Beránek P, Posocco P, Posel Z. Phase Behavior of Gradient Copolymer Melts with Different Gradient Strengths Revealed by Mesoscale Simulations. Polymers (Basel) 2020; 12:E2462. [PMID: 33114271 PMCID: PMC7690882 DOI: 10.3390/polym12112462] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Revised: 10/19/2020] [Accepted: 10/21/2020] [Indexed: 11/16/2022] Open
Abstract
Design and preparation of functional nanomaterials with specific properties requires precise control over their microscopic structure. A prototypical example is the self-assembly of diblock copolymers, which generate highly ordered structures controlled by three parameters: the chemical incompatibility between blocks, block size ratio and chain length. Recent advances in polymer synthesis have allowed for the preparation of gradient copolymers with controlled sequence chemistry, thus providing additional parameters to tailor their assembly. These are polydisperse monomer sequence, block size distribution and gradient strength. Here, we employ dissipative particle dynamics to describe the self-assembly of gradient copolymer melts with strong, intermediate, and weak gradient strength and compare their phase behavior to that of corresponding diblock copolymers. Gradient melts behave similarly when copolymers with a strong gradient are considered. Decreasing the gradient strength leads to the widening of the gyroid phase window, at the expense of cylindrical domains, and a remarkable extension of the lamellar phase. Finally, we show that weak gradient strength enhances chain packing in gyroid structures much more than in lamellar and cylindrical morphologies. Importantly, this work also provides a link between gradient copolymers morphology and parameters such as chemical incompatibility, chain length and monomer sequence as support for the rational design of these nanomaterials.
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Affiliation(s)
- Pavel Beránek
- Department of Informatics, Faculty of Science, Jan Evangelista Purkyně University in Ústí nad Labem, 40096 Ústí nad Labem, Czech Republic;
| | - Paola Posocco
- Department of Engineering and Architecture, University of Trieste, 34127 Trieste, Italy;
| | - Zbyšek Posel
- Department of Informatics, Faculty of Science, Jan Evangelista Purkyně University in Ústí nad Labem, 40096 Ústí nad Labem, Czech Republic;
- Department of Engineering and Architecture, University of Trieste, 34127 Trieste, Italy;
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9
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Raya RK, Štěpánek M, Limpouchová Z, Procházka K, Svoboda M, Lísal M, Pavlova E, Skandalis A, Pispas S. Onion Micelles with an Interpolyelectrolyte Complex Middle Layer: Experimental Motivation and Computer Study. Macromolecules 2020. [DOI: 10.1021/acs.macromol.0c00560] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Rahul Kumar Raya
- Department of Physical and Macromolecular Chemistry, Faculty of Science, Charles University in Prague, Hlavova 2030, 12840 Prague 2, Czech Republic
| | - Miroslav Štěpánek
- Department of Physical and Macromolecular Chemistry, Faculty of Science, Charles University in Prague, Hlavova 2030, 12840 Prague 2, Czech Republic
| | - Zuzana Limpouchová
- Department of Physical and Macromolecular Chemistry, Faculty of Science, Charles University in Prague, Hlavova 2030, 12840 Prague 2, Czech Republic
| | - Karel Procházka
- Department of Physical and Macromolecular Chemistry, Faculty of Science, Charles University in Prague, Hlavova 2030, 12840 Prague 2, Czech Republic
| | - Martin Svoboda
- Department of Physics, Faculty of Science, J. E. Purkinje University, České mládeže 8, 400 96 Ústí n. Lab., Czech Republic
- Department of Molecular and Mesoscopic Modelling, Institute of Chemical Process Fundamentals of the CAS, Rozvojová 135/1, 165 02 Prague 6, Suchdol, Czech Republic
| | - Martin Lísal
- Department of Physics, Faculty of Science, J. E. Purkinje University, České mládeže 8, 400 96 Ústí n. Lab., Czech Republic
- Department of Molecular and Mesoscopic Modelling, Institute of Chemical Process Fundamentals of the CAS, Rozvojová 135/1, 165 02 Prague 6, Suchdol, Czech Republic
| | - Ewa Pavlova
- Department of Polymer Morphology, Institute of Macromolecular Chemistry of the CAS, Heyrovský Square 2, 160 00 Prague 6, Czech Republic
| | - Athanasios Skandalis
- Theoretical & Physical Chemistry Institute, National Hellenic Research Foundation, 48 Vassileos Constantinou Avenue, 11635 Athens, Greece
| | - Stergios Pispas
- Theoretical & Physical Chemistry Institute, National Hellenic Research Foundation, 48 Vassileos Constantinou Avenue, 11635 Athens, Greece
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10
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Speyer K, Pastorino C. Pressure responsive gating in nanochannels coated by semiflexible polymer brushes. SOFT MATTER 2019; 15:937-946. [PMID: 30644495 DOI: 10.1039/c8sm02388c] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
We study by coarse-grained molecular-dynamics simulations the liquid flow in a slit channel with the inner walls coated by semiflexible polymer brushes. The distance between walls is close enough such that polymers grafted to opposing walls interact among each other and form bundles across the channel in poor solvent conditions. The solvent is simulated explicitly, including particles that fill the interior of the channel. The system is studied in equilibrium and under flow, by applying a constant body force on each particle of the system. A non-linear relation between external force and flow rate is observed, for a particular set of parameters. This non-linear response is linked to a morphological change of the polymer brushes. For large enough forces, the bundle structures formed across the channel break as the chains lean in the direction of the flow, and clear the middle of the channel. This morphological alteration of the polymer configurations translates in a sudden increase in the flow rate, acting as a pressure-responsive gate. The relation between flow and external force is investigated for various parameters, such as grafting density, quality of the solvent and polymer bending rigidity. We observe a non-monotonic dependence of the flow as a function of the polymer rigidity, and find an optimum value for the persistence length. We also find that the force threshold at which the morphological changes happen in the polymer brush, depends linearly on the grafting density. These findings can lead to new flow control techniques in micro and nano-fluidic devices.
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Affiliation(s)
- K Speyer
- Departamento de Física de la Materia Condensada, Centro Atómico Constituyentes, CNEA, Av. Gral. Paz 1499, 1650 Pcia. de Buenos Aires, Argentina.
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11
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Seaton MA. DL_MESO_DPD: development and use of mesoscale modelling software. MOLECULAR SIMULATION 2018. [DOI: 10.1080/08927022.2018.1524143] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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13
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Hideo D, Koji O, Takamitsu N, Sona S, Yuji M. A portable code for dissipative particle dynamics (DPD) simulations with additional specific interactions. CHEM-BIO INFORMATICS JOURNAL 2018. [DOI: 10.1273/cbij.18.70] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- Doi Hideo
- Department of Chemistry and Research Center for Smart Molecules, Faculty of Science, Rikkyo University
| | - Okuwaki Koji
- Department of Chemistry and Research Center for Smart Molecules, Faculty of Science, Rikkyo University
| | - Naito Takamitsu
- Department of Chemistry and Research Center for Smart Molecules, Faculty of Science, Rikkyo University
| | - Saitou Sona
- Department of Chemistry and Research Center for Smart Molecules, Faculty of Science, Rikkyo University
| | - Mochizuki Yuji
- Department of Chemistry and Research Center for Smart Molecules, Faculty of Science, Rikkyo University
- Institute of Industrial Science, The University of Tokyo
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14
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Posel Z, Svoboda M, Limpouchová Z, Lísal M, Procházka K. Adsorption of amphiphilic graft copolymers in solvents selective for the grafts on a lyophobic surface: a coarse-grained simulation study. Phys Chem Chem Phys 2018; 20:6533-6547. [DOI: 10.1039/c7cp08327k] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The sorption of graft copolymers on surfaces attractive only for the backbone and its effect on the conformational behavior of adsorbed/desorbed chains in solvents good for the grafts and poor for the backbone was studied by coarse-grained computer simulations.
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Affiliation(s)
- Zbyšek Posel
- Department of Informatics, Faculty of Science, J. E. Purkinje University
- Czech Republic
- Department of Molecular and Mesoscale Modelling, Institute of Chemical Process Fundamentals of CAS, v. v. i
- 165 02 Prague 6-Suchdol
- Czech Republic
| | - Martin Svoboda
- Department of Molecular and Mesoscale Modelling, Institute of Chemical Process Fundamentals of CAS, v. v. i
- 165 02 Prague 6-Suchdol
- Czech Republic
- Department of Physics, Faculty of Science, J. E. Purkinje University
- Czech Republic
| | - Zuzana Limpouchová
- Department of Physical and Macromolecular Chemistry, Faculty of Science, Charles University in Prague
- Prague 2
- Czech Republic
| | - Martin Lísal
- Department of Molecular and Mesoscale Modelling, Institute of Chemical Process Fundamentals of CAS, v. v. i
- 165 02 Prague 6-Suchdol
- Czech Republic
- Department of Physics, Faculty of Science, J. E. Purkinje University
- Czech Republic
| | - Karel Procházka
- Department of Physical and Macromolecular Chemistry, Faculty of Science, Charles University in Prague
- Prague 2
- Czech Republic
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15
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Shang X, Kröger M, Leimkuhler B. Assessing numerical methods for molecular and particle simulation. SOFT MATTER 2017; 13:8565-8578. [PMID: 29099134 DOI: 10.1039/c7sm01526g] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
We discuss the design of state-of-the-art numerical methods for molecular dynamics, focusing on the demands of soft matter simulation, where the purposes include sampling and dynamics calculations both in and out of equilibrium. We discuss the characteristics of different algorithms, including their essential conservation properties, the convergence of averages, and the accuracy of numerical discretizations. Formulations of the equations of motion which are suited to both equilibrium and nonequilibrium simulation include Langevin dynamics, dissipative particle dynamics (DPD), and the more recently proposed "pairwise adaptive Langevin" (PAdL) method, which, like DPD but unlike Langevin dynamics, conserves momentum and better matches the relaxation rate of orientational degrees of freedom. PAdL is easy to code and suitable for a variety of problems in nonequilibrium soft matter modeling; our simulations of polymer melts indicate that this method can also provide dramatic improvements in computational efficiency. Moreover we show that PAdL gives excellent control of the relaxation rate to equilibrium. In the nonequilibrium setting, we further demonstrate that while PAdL allows the recovery of accurate shear viscosities at higher shear rates than are possible using the DPD method at identical timestep, it also outperforms Langevin dynamics in terms of stability and accuracy at higher shear rates.
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Affiliation(s)
- Xiaocheng Shang
- Department of Materials, Polymer Physics, ETH Zürich, CH-8093 Zürich, Switzerland.
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16
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Liu YT, Li YR, Wang X. Dynamic evolution of a vesicle formed by comb-like block copolymer-tethered nanoparticles: a dissipative particle dynamics simulation study. Phys Chem Chem Phys 2017; 19:27313-27319. [DOI: 10.1039/c7cp05196d] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Vesicles are well-sealed capsules that can store or transport substances.
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Affiliation(s)
- Ying-Tao Liu
- School of Chemistry and Chemical Engineering
- Ningxia University
- Yinchuan
- China
| | - Yan-Rong Li
- School of Chemistry and Chemical Engineering
- Ningxia University
- Yinchuan
- China
| | - Xin Wang
- School of Chemistry and Chemical Engineering
- Ningxia University
- Yinchuan
- China
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