Static electronic susceptibility, (q,z,z), of the Lang-Kohn jellium surface

We present the first accurate values of (q,z,z), the static susceptibility of a jellium surface, including (i) finite surface wave vector q; (ii) Friedel oscillations (from an exact kinetic energy functional); (iii) Kohn-Sham exchange-correlation effects (Wigner form); (iv) self-consistent screening; (v) realistic Lang-Kohn zero-order profile; and (vi) comparison, for rs=2.07, with a useful approximation.