0000000000659137

AUTHOR

J. Baschnagel

showing 3 related works from this author

Anomalous diffusion of polymers in supercooled melts near the glass transition

2007

Two coarse-grained models for polymer chains in dense melts near the glass transition are investigated: the bond fluctuation lattice model, where long bonds are energetically favored, is studied by dynamic Monte Carlo simulation, and an off-lattice bead-spring model with Lennard-Jones forces between the beads is treated by Molecular Dynamics. We compare the time-dependence of the mean square displacements of both models, and show that they become very similar on mesoscopic scales (i.e., displacements larger than a bond length). The slowing down of motions near the glass transition is discussed in terms of the mode coupling theory and other concepts.

Condensed Matter::Soft Condensed MatterPhysicsBond lengthQuantitative Biology::BiomoleculesMesoscopic physicsMolecular dynamicsCondensed matter physicsAnomalous diffusionMonte Carlo methodSupercoolingGlass transitionLattice model (physics)
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Computer simulation of models for the structural glass transition

2008

In order to test theoretical concepts on the glass transition, we investigate several models of glassy materials by means of Monte Carlo (MC) and Molecular Dynamics (MD) computer simulations. It is shown that also simplified models exhibit a glass transition which is in qualitative agreement with experiment and that thus such models are useful to study this phenomenon. However, the glass transition temperture as well as the structural properties of the frozen-in glassy phase depend strongly on the cooling history, and the extrapolation to the limit of infinitely slow cooling velocity is nontrivial, which makes the identification of the (possible) underlying equilibrium transition very diffi…

PhysicsMolecular dynamicsSlow coolingPhase (matter)Monte Carlo methodEnthalpyExtrapolationThermodynamicsLimit (mathematics)Statistical physicsGlass transitionCondensed Matter::Disordered Systems and Neural Networks
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Monte-Carlo Simulation of 3-Dimensional Glassy Polymer Melts: Reptation Versus Single Monomer Dynamics

1995

A polymer melt is simulated at finite temperature by the Monte-Carlo method. We use a coarse-grained model for the polymer system, the bond-fluctuation model. Static properties of the melt can be obtained by generating configurations not with single-monomer- dynamics which moves individual monomers locally, but reptation-dynamics which allows collec- tive motion of the chains. This algorithm can produce equilibrated configurations much faster. It is demonstrated that static properties do not differ from those obtained by single-monomer- dynamics. Values of the radius of gyration, the mean square bond length and similar quantities for different temperatures and densities are presented.

chemistry.chemical_classificationQuantitative Biology::BiomoleculesPhysics and Astronomy (miscellaneous)Dynamics (mechanics)Monte Carlo methodGeneral EngineeringThermodynamicsPolymerAtomic and Molecular Physics and OpticsCondensed Matter::Soft Condensed MatterBond lengthchemistry.chemical_compoundReptationMonomerchemistryRadius of gyrationStatistical physicsPolymer meltJournal de Physique II
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