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Is there Ornstein-Zernike equation in the canonical ensemble?

J. A. White·S. Velasco
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Abstract

A general density-functional formalism using an extended variable-space is presented for classical fluids in the canonical ensemble (CE). An exact equation is derived that plays the role of the Ornstein-Zernike (OZ) equation in the grand canonical ensemble (GCE). When applied to the ideal gas we obtain the exact result for the total correlation function h_N. For a homogeneous fluid with N particles the new equation only differs from OZ by 1/N and it allows to obtain an approximate expression for h_N in terms of its GCE counterpart that agrees with the expansion of h_N in powers of 1/N.

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J. A. White, S. Velasco. 2000-09-07. Is there Ornstein-Zernike equation in the canonical ensemble?. https://doi.org/10.1209/epl%2Fi2001-00270-x

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