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Two hard spheres in a spherical pore: Exact analytic results in two and three dimensions

Ignacio Urrutia
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Abstract

The partition function and the one- and two-body distribution functions are evaluated for two hard spheres with different sizes constrained into a spherical pore. The equivalent problem for hard disks is addressed too. We establish a relation valid for any dimension between these partition functions, second virial coefficient for inhomogeneous systems in a spherical pore, and third virial coefficients for polydisperse hard spheres mixtures. Using the established relation we were able to evaluate the cluster integral $b_{2}(V)$ related with the second virial coefficient for the Hard Disc system into a circular pore. Finally, we analyse the behaviour of the obtained expressions near the maximum density.

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Ignacio Urrutia. 2008-04-28. Two hard spheres in a spherical pore: Exact analytic results in two and three dimensions. https://doi.org/10.1007/s10955-088-9513-3

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