Mixing effects for the structural relaxation in binary hard-sphere liquids.
We report extensive molecular-dynamics-simulation results for binary mixtures of hard spheres for different size disparities and different mixing percentages, for packing fractions up to 0.605, and over a characteristic time interval spanning up to 5 orders in magnitude. We explore the changes in the evolution of glassy dynamics due to mixing and discover two opposite scenarios: For large size disparity, increasing the mixing percentage of small particles leads to a speed up of long-time dynamics, while small disparity leads to a slowing down. These results agree with predictions based on the mode-coupling theory for ideal-glass transitions.
Foffi
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Dipartimento di Fisica and INFM Center for Statistical Mechanics and Complexity, Università di Roma La Sapienza, Piazzale Aldo Moro 2, 00185 Rome, Italy.
Götze
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W
Sciortino
F
F
Tartaglia
P
P
Voigtmann
Th
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