Using molecular-dynamics simulations, calculations were made of the distribution of atomic jumps in Cu33Zr67 in the liquid and glassy states. In both states, the distribution of jump lengths could be described by a temperature-independent exponential of the length and an effective activation energy plus a contribution of elastic displacements at short distances. Upon cooling, the contribution of shorter jumps predominated. No indication of an enhanced probability of jumping over a nearest-neighbor distance was found. A smooth transition from flow in the liquid to jumps in the glass was found. The correlation factor of the diffusion constant decreased with decreasing temperature, causing a drop in diffusion below the Arrhenius value, in spite of an apparent Arrhenius law for the jump probability.

Diffusion and Jump-Length Distribution in Liquid and Amorphous Cu33Zr67. M.Kluge, H.R.Schober: Physical Review B, 2004, 70[22], 224209 (12pp)