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Diffusion and jump-length distribution in liquid and amorphous Cu$_{33}$Zr$_{67}$

M. Kluge·H. R. Schober
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Abstract

Using molecular dynamics simulation, we calculate the distribution of atomic jum ps in Cu$_{33}$Zr$_{67}$ in the liquid and glassy states. In both states the distribution of jump lengths can 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 dominates. No indication of an enhanced probability to jump over a nearest neighbor distance was found. We find a smooth transition from flow in the liquid to jumps in the g lass. The correlation factor of the diffusion constant decreases with decreasing temperature, causing a drop of diffusion below the Arrhenius value, despite an apparent Arrhenius law for the jump probability.

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M. Kluge, H. R. Schober. 2005-02-25. Diffusion and jump-length distribution in liquid and amorphous Cu$_{33}$Zr$_{67}$. https://doi.org/10.1103/physrevb.70.224209

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