Efficient calculation of bulk jellium electronic susceptibilities for use in the theory of metal surfaces

The authors present convenient expressions for both the unscreened static electronic Lindhard susceptibility, chi 0(q/sub ///,z), and for the screened chi (q/sub ///,z), within both the RPA (random-phase approximation) and the LDF (local density functional) theories. The efficient methods for calculating the bulk chi s presented here are useful because the bulk chi s, in (q/sub ///,z) representation, are the basic ingredients in a very accurate mimic function of the equivalent surface susceptibilities.