DIELECTRIC FUNCTION OF THE 2-DIMENSIONAL ELECTRON LIQUID - AN ANALYTICAL FITTING

For electron-electron interactions in two-dimensional electronic syste ms the technique proposed by Singwi, Tosi, Land, and Sjolander (STLS) has been very promising. In this work, after showing the asymptotic be havior of the STLS local held correction we propose a simple expressio n for the local-held correction that contains two fitting parameters w hich are smoothly varying functions of the electronic density. The agr eement of the fitting for the pair correlation function is remarkable. It further leads to an expression for the dielectric function which c an be useful for applications. Finally, to assess the accuracy of the STLS technique, especially at low electronic densities we compare the STLS results with the available quantum Monte Carlo data.