Surface properties of simple metals via inhomogeneous linear electronic response. I. Theory

This paper is the first of a series addressing the macroscopic surface properties of the simple metals (the alkalis, Mg, Zn, Al, Pb) using pseudopotential perturbation theory to include the effects of discrete ions beyond the first-order Lang-Kohn jellium calculation. Here the authors give explicit formulae for the self-consistently screened inhomogeneous electron susceptibility chi (q//, z, z') calculated around the jellium surface results of Lang and Kohn (1970). In terms of chi they then give explicit formulae, up to second order in the ionic pseudopotentials, for: (i) the energy of a bounded metal; (ii) the effective ion and ion-ion potentials near a surface; (iii) the unreconstructed surface formation energy sigma at T=0K; (iv) the surface dynamical matrix; (v) the relaxation of ionic layer positions due to the surface; (vi) approximate T not=0K contributions to the surface free energy in the solid phase. As tested on face-dependent surface energies, their second-order method is a decided improvement on first-order theories, and on one-dimensional variational theories. It has a further advantage over variational approaches in that expressions for (iv), (v) and (vi) can be given in analytic form.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/48998/2/jcv15i36p7429.pd