Equivalence between Wolf and Yukawa non-homogeneous fluids in a gravitational field

Abstract

A density functional description for a charged fluid immersed in a gravitational field is presented, using a local density approximation. The screened pair electrostatic interaction between particles is described with the Wolf potential model, and a thermodynamic perturbation theory is used to obtain the homogeneous free energy required by the local density approximation. Density profiles behaviour is explored for the Wolf fluid as a function of the potential range, temperature and bulk density. An approximate equivalence based on kinetic theory is applied to relate the range parameters of Wolf and Yukawa potentials. Through a detailed comparison among the local density profiles of both fluid descriptions, a precise correspondence relationship between Yukawa and Wolf non-homogeneous fluids can be established.