6533b7d4fe1ef96bd1262981

RESEARCH PRODUCT

Scaling behavior in the $\beta$-relaxation regime of a supercooled Lennard-Jones mixture

Walter KobHans C. Andersen

subject

PhysicsMolecular dynamicsCondensed matter physicsExponentGeneral Physics and AstronomyThermodynamicsRelaxation (physics)Beta (velocity)Function (mathematics)Condensed MatterDiffusion (business)SupercoolingScaling

description

We report the results of a molecular dynamics simulation of a supercooled binary Lennard-Jones mixture. By plotting the self intermediate scattering functions vs. rescaled time, we find a master curve in the $\beta$-relaxation regime. This master curve can be fitted well by a power-law for almost three decades in rescaled time and the scaling time, or relaxation time, has a power-law dependence on temperature. Thus the predictions of mode-coupling-theory on the existence of a von Schweidler law are found to hold for this system; moreover, the exponents in these two power-laws are very close to satisfying the exponent relationship predicted by the mode-coupling-theory. At low temperatures, the diffusion constants also show a power-law behavior with the same critical temperature. However, the exponent for diffusion differs from that of the relaxation time, a result that is in disagreement with the theory.

10.1103/physrevlett.73.1376http://arxiv.org/abs/cond-mat/9407118