Collective Diffusion of Multi-Component Liquids

The collective diffusion of simple liquids is understood in terms of thermal diffusivity in the hydrodynamic limit. However, the collective diffusion of multi-component liquids has not been reported, especially at the local molecular length scales where the continuous and isotropic symmetries are broken. We studied the collective diffusion of a series of liquids with an increasing number of constituents. By analyzing the structural and dynamic correlation functions of the systems, we revealed the role of mixing entropy and elemental fluctuations in determining the collective diffusion of multi-component liquids.