One and two-component hard core plasmas

Roland R. Netz; H. Orland

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arXiv · cond-mat/9902220

One and two-component hard core plasmas

Roland R. Netz·H. Orland

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Abstract

A field theory is presented for particles which interact via Coulomb and hard-core potentials. We apply the method to the one-component plasma (OCP) with hard cores, consisting of identical particles of fixed charge and diameter in a neutralizing background, and the symmetric two-component plasma (TCP) with hard cores, consisting of equal numbers of positively and negatively charged particles of identical size. We obtain exactly the first few coefficients of a systematic low-density expansion of the free energy for both models. The OCP coefficients go over to the classical Abe result in the high-charge (or small hard-core diameter) limit. The TCP, on the other hand, exhibits diverging coefficients in the high-charge limit, which is due to the formation of strongly bound ion-pairs.

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Roland R. Netz, H. Orland. 1999-02-16. One and two-component hard core plasmas. https://arxiv.org/abs/cond-mat/9902220

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