Analytic fit to the one-component-plasma structure factor

Abstract

We use a nonlinear least-squares-fitting program to find an analytic fit to the one-component plasma fluid structure factor S(q,\ensuremath{\Gamma}) over the ranges 0\ensuremath{\le}q\ensuremath{\le}21.75 and 1\ensuremath{\le}\ensuremath{\Gamma}\ensuremath{\le}225. The S(q,\ensuremath{\Gamma}) function is generated as a table from the solution of the modified hypernetted chain integral equation. The table is fitted with polynomials in q and \ensuremath{\Gamma}, using a total of 175 coefficients. The overall fit is good, suggesting that the fitting method might be applied successfully to other distribution functions.