Search results for "Premelting"

showing 5 items of 5 documents

Molecular dynamics investigation of the premelting effects of Lennard-Jones (111) surfaces

1987

Molecular dynamics simulations have been performed to study the premelting effects of noble-gas surfaces (argon) close to but below the bulk melting temperature. In particular, the increase of disorder as a function of temperature at (111) surface has been considered. The truncated Lennard-Jones (6-12) potential is used to describe the interactions between particles. Surface premelting has been analyzed by means of total energies, trajectory plots, mean sequare displacement functions, diffusion coefficients, vacancy concentrations and two-dimensional order parameters. The (111) surface starts to disorder by vacancy formation, which leads to the premelting of the surface layer far below the …

Materials scienceArgonDiffusionThermodynamicschemistry.chemical_elementCondensed Matter PhysicsAtomic and Molecular Physics and OpticsPremeltingMolecular dynamicsSphere packingchemistryVacancy defectPhysics::Atomic and Molecular ClustersSurface layerDisplacement (fluid)Mathematical PhysicsPhysica Scripta
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Interfacial premelting of ice in nano composite materials

2018

Physical chemistry, chemical physics 21, 3734 - 3741 (2019). doi:10.1039/C8CP05604H

Materials scienceGeneral Physics and AstronomyThermodynamics02 engineering and technologyAtmospheric temperature rangeVermiculite540010402 general chemistry021001 nanoscience & nanotechnologyPermafrost01 natural sciences0104 chemical sciencesPremeltingSoil waterddc:540Melting pointIce nucleusPhysical and Theoretical Chemistry0210 nano-technologyClay minerals
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Computer simulation of disordering and premelting of low-index faces of copper.

1992

Molecular dynamics and the effective-medium theory have been applied to investigate the structure and dynamics of (110), (100), and (111) faces of copper in the whole temperature range from 0 K up to the bulk melting point, which has been determined to be 1240\ifmmode\pm\else\textpm\fi{}25 K. The observed order in the surface stability follows the order in the packing density. (110) disorders first via anharmonic effects (up to 700 K), then by vacancy-adatom formation and finally by premelting of the surface at about 1200 K. The (110) solid-melt interface is anisotropic and broadened, having a tendency to form small fluctuating (111) facets in equilibrium, which is suggested to be the atomi…

SuperheatingMolecular dynamicsMaterials sciencechemistryAnharmonicityMelting pointchemistry.chemical_elementThermodynamicsAtmospheric temperature rangeAnisotropyCopperPremeltingPhysical review. B, Condensed matter
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Molecular Dynamics Study of Disordering and Premelting of the Pb(110) Surface

1994

Molecular dynamics simulations incorporating a many-body (glue) potential have been used to investigate the atomic structure and dynamics of the Pb(110) surface in the range from room temperature up to the bulk melting point. The Pb (110) surface starts to disorder approximately at 360 K via the generation of vacancies and the formation of an adlayer. At about 520 K we observe the onset of a quasiliquid region at the surface, which exhibits liquid-like energetic, structural and surface properties. The disordering is enhanced in the direction parallel to the close-packed rows. While losing long range order, the two outermost quasiliquid layers retain a considerable degree of short range orde…

Surface (mathematics)Range (particle radiation)Molecular dynamicsMaterials scienceCondensed matter physicsShort range orderMelting pointDegree (temperature)PremeltingMRS Proceedings
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DISORDERING MECHANISMS OF THE Cu(110) SURFACE

1994

We review recent theoretical work on the various disordering mechanisms of the Cu(110) surface. In these studies the properties of the surface, from the onset of enhanced anharmonicity in surface vibrations up to bulk melting point T M , have been studied using molecular dynamics and lattice-gas Monte Carlo methods with many-body interactions derived from the effective medium theory. Well after the onset of enhanced out-of-plane surface vibrations, clustering of surface defects is found to induce a roughening transition at T≈0.81T M , and surface premelting is found to occur at T≈0.97T M . These results suggest, that these transitions can both appear at Cu(110). The general picture of diso…

Work (thermodynamics)Materials scienceCondensed matter physicsAnharmonicitychemistry.chemical_elementStatistical and Nonlinear Physics02 engineering and technologyCrystal structure021001 nanoscience & nanotechnologyCondensed Matter Physics01 natural sciencesCopperCrystallographic defectPremeltingMolecular dynamicschemistry0103 physical sciencesMelting point010306 general physics0210 nano-technologyInternational Journal of Modern Physics B
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