Addendum to "Equation of state of classical Coulomb plasma mixtures"

Ioffe Physical-Technical Institute, St. Petersburg, Russia.
Physical Review E (Impact Factor: 2.29). 10/2009; 80(4 Pt 2):047401. DOI: 10.1103/PHYSREVE.80.047401
Source: PubMed


Recently developed analytic approximation for the equation of state of fully ionized nonideal electron-ion plasma mixtures [A. Y. Potekhin, G. Chabrier, and F. J. Rogers, Phys. Rev. E 79, 016411 (2009)], which covers the transition between the weak and strong Coulomb coupling regimes and reproduces numerical results obtained in the hypernetted-chain (HNC) approximation, is modified in order to fit the small deviations from the linear mixing in the strong-coupling regime, revealed by recent Monte Carlo simulations. In addition, a mixing rule is proposed for the regime of weak coupling, which generalizes post-Debye density corrections to the case of mixtures and numerically agrees with the HNC approximation in that regime.

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