Different thermodynamic pathways to the solvation free energy of a spherical cavity in a hard sphere fluid

Yng-gwei Chen; John D. Weeks

doi:10.1063/1.1563592

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Different thermodynamic pathways to the solvation free energy of a spherical cavity in a hard sphere fluid

Yng-gwei Chen·John D. Weeks

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Abstract

This paper determines the excess free energy associated with the formation of a spherical cavity in a hard sphere fluid. The solvation free energy can be calculated by integration of the structural changes induced by inserting the cavity using a number of different exact thermodynamic pathways. We consider three such pathways, including a new density route derived here. Structural information about the nonuniform hard sphere fluid in the presence of a general external field is given by the recently developed hydrostatic linear response (HLR) integral equation. Use of the HLR results in the different pathways gives a generally accurate determination of the solvation free energy for cavities over a wide range of sizes, from zero to infinity. Results for a related method, the Gaussian Field Model, are also discussed.

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Yng-gwei Chen, John D. Weeks. 2003-01-19. Different thermodynamic pathways to the solvation free energy of a spherical cavity in a hard sphere fluid. https://doi.org/10.1063/1.1563592

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