COORDINATE SPACE FORM OF INTERACTING REFERENCE RESPONSE FUNCTION OF JELLIUM MODEL OF AN ELECTRON LIQUID

The interacting reference response function chi(I)(k) of jellium in k space is defined, according to Niklasson (1974), in terms of the momen tum distribution n(p) of the interacting electron liquid in a similar way as the Lindhard function chi(I)(k) in terms of the Fermi distribut ion n(O)(p). Here the Fourier transform F-I(f) of chi(I)(k) is investi gated. Using the known analytic behaviour of n(p), the small and large r forms of F-I are exhibited explicitly. In an Appendix, it is shown that a suitable model of n(p) can be constructed which interpolates be tween these limits. Some brief comments are added concerning the repre sentation of F-I(r) in terms of the Green function.