We analyse the experimental particle current auto correlation function (CAF) of suspensions of hard spheres. Interactions between the particles are mediated by thermally activated acoustic excitations in the solvent. Those acoustic modes are tantamount to the systems (energy) microstates and by their orthogonality, each of those modes can be identified with an independent Brownian particle current. Accordingly, partitioning of the systems energy states is impressed on the CAF. This impression provides a novel measure of the entropy and location of a partitioning/entropy limit at a packing fraction that coincides with that of the observed suspensions first order freezing transition.
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