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arXiv · 0903.3877

A branch-point approximant for the equation of state of hard spheres

Andrés Santos·Mariano López de Haro
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Abstract

Using the first seven known virial coefficients and forcing it to possess two branch-point singularities, a new equation of state for the hard-sphere fluid is proposed. This equation of state predicts accurate values of the higher virial coefficients, a radius of convergence smaller than the close-packing value, and it is as accurate as the rescaled virial expansion and better than the Padé [3/3] equations of state. Consequences regarding the convergence properties of the virial series and the use of similar equations of state for hard-core fluids in $d$ dimensions are also pointed out.

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Andrés Santos, Mariano López de Haro. 2009-06-26. A branch-point approximant for the equation of state of hard spheres. https://doi.org/10.1063/1.3147723

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