Scaling Behavior in the<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mi>β</mml:mi></mml:math>-Relaxation Regime of a Supercooled Lennard-Jones Mixture

Abstract

We have performed molecular dynamics simulations of a supercooled atomic liquid. The self-intermediate-scattering function in the $\ensuremath{\beta}$-relaxation regime has a power-law time dependence and temperature dependence consistent with the mode-coupling-theory prediction of a von Schweidler law, with exponents that are very close to satisfying the exponent relationship predicted by the theory. The diffusion constants have a power-law dependence on temperature with the same critical temperature. The exponents for diffusion differ from those of the relaxtion time, a result that is in disagreement with the theory.