Configuration space formulation and implications for approximation schemes for strongly coupled plasmas

An approximation formulated in terms of equations in the configuration space has been developed to describe strongly-coupled plasmas. The Singwi, Tosi, Land and Sjolander (1968) and Totsuji and Ichimaru (1973) equations, transformed to r-space, appear as Poisson equations for the direct correlation function, with distinctive source terms involving the pair correlation function. The source structure of this approximation is compared with those of other approximation schemes. It is shown that the source equation and the Ornstein-Zernike relation connecting the direct and the pair correlation functions can be solved simultaneously for certain simple cases. A method for determining the small-r behavior of the correlation functions is presented various schemes are found to have anomalous small-r behavior