SCALING BEHAVIOR IN THE BETA-RELAXATION REGIME OF A SUPERCOOLED LENNARD-JONES MIXTURE

We have performed molecular dynamics simulations of a supercooled atomic liquid. The self-intermediate-scattering function in the 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 relaxation time, a result that is in disagreement with the theory.