Computation of the Hydrodynamic Radius of Charged Nanoparticles from Nonequilibrium Molecular Dynamics
| Autor: | Vincent Dahirel, Virginie Marry, Lisa B. Weiss, Marie Jardat |
|---|---|
| Přispěvatelé: | PHysicochimie des Electrolytes et Nanosystèmes InterfaciauX (PHENIX), Université Pierre et Marie Curie - Paris 6 (UPMC)-Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), Liquides Ioniques et Interfaces Chargées (LI2C), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS) |
| Rok vydání: | 2018 |
| Předmět: |
Hydrodynamic radius
Materials science FOS: Physical sciences Non-equilibrium thermodynamics Nanoparticle 02 engineering and technology Condensed Matter - Soft Condensed Matter 010402 general chemistry 01 natural sciences Atomic units Ion law.invention law Materials Chemistry Physical and Theoretical Chemistry ComputingMilieux_MISCELLANEOUS Condensed Matter - Statistical Mechanics Statistical Mechanics (cond-mat.stat-mech) Mechanics [CHIM.MATE]Chemical Sciences/Material chemistry 021001 nanoscience & nanotechnology Thermostat Symmetry (physics) 0104 chemical sciences Surfaces Coatings and Films Flow (mathematics) Soft Condensed Matter (cond-mat.soft) 0210 nano-technology |
| Zdroj: | J. Phys. Chem. B Journal of Physical Chemistry B Journal of Physical Chemistry B, American Chemical Society, 2018, 122 (22), pp.5940-5950 |
| ISSN: | 1520-5207 1520-6106 |
| Popis: | We have used non-equilibrium molecular dynamics to simulate the flow of water molecules around a charged nanoparticle described at the atomic scale. These non-equilibrium simulations allowed us to compute the friction coefficient of the nanoparticle and then to deduce its hydrodynamic radius. We have compared two different strategies to thermostat the simulation box, since the low symmetry of the flow field renders the control of temperature non trivial. We show that both lead to an adequate control of the temperature of the system. To deduce the hydrodynamic radius of the nanoparticle we have employed a partial thermostat, which exploits the cylindrical symmetry of the flow field. Thereby, only a part of the simulation box far from the nanoparticle is thermostated. We have taken into account the finite concentration of the nanoparticle by using the result of Hasimoto (J. Fluid. Mech. {\bf 1959}, {\it 5}, 317-328 ) for the friction force in a periodic cubic array of spheres. We have focused on the case of polyoxometalate ions, which are inorganic charged nanoparticles. It appears that, for a given structure of the nanoparticle at the atomic level, the hydrodynamic radius significantly increases with the nanoparticle's charge, a phenomenon that had not been quantified so far using molecular dynamics. The presence of an added salt only slightly modifies the hydrodynamic radius. submitted to J. Phys. Chem. B |
| Databáze: | OpenAIRE |
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