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arXiv · 2012.05594

Fluctuation profiles in inhomogeneous fluids

Tobias Eckert·Nex C. X. Stuhlmüller·Florian Sammüller·Matthias Schmidt
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Abstract

Three one-body profiles that correspond to local fluctuations in energy, in entropy, and in particle number are used to describe the equilibrium properties of inhomogeneous classical many-body systems. Local fluctuations are obtained from thermodynamic differentiation of the density profile or equivalently from average microscopic covariances. The fluctuation profiles follow from functional generators and they satisfy Ornstein-Zernike relations. Computer simulations reveal markedly different fluctuations in confined fluids with Lennard-Jones, hard sphere, and Gaussian core interactions.

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Tobias Eckert, Nex C. X. Stuhlmüller, Florian Sammüller, Matthias Schmidt. 2020-12-10. Fluctuation profiles in inhomogeneous fluids. https://doi.org/10.1103/physrevlett.125.268004

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