Self-consistent Screening in the alkali metals

Abstract

Abstract Systematic calculations of the screening of a pseudo-atom in the alkali metals are presented. These calculations are performed with and without the exchange, correlation and orthogonalization corrections. The results are compared with ‘experimental’ phase-shifts, and show that the Screened Uniform Charge Model and our self-consistent screening procedure can accurately predict band-structures. We also show that the correlation correction should not be used. The orthogonalization corrections m E(kF )) -1 are calculated and the nature of the depletion hole in lithium is discussed. The phase-shifts are used to calculate the sensitivities p of the liquid metals; the difference between the calculated and experimental values of p correlates both with the deviation from free-electron behaviour and with m E(kF )) -1 We conjecture that the form-factor in the S.U.C.M. needs modification to take into account the change, due to orthogonalization, in charge density in the interstitial regions.