Interpolation scheme for dynamic electron correlations in the electron gas

Abstract

An analytical interpolation scheme is proposed to include correlation effects in the local-field correction G( q, ω) of the electron gas. Rigorous asymptotic limits of G( q, ω) for large and small wave vectors and frequencies are combined with the known frequency dependent behaviour of G( q, ω), as revealed by the time-dependent HF-approximation. The correct interpretation of the known sum rules in the limits of small and large wave vectors and frequencies is of crucial importance for estimating the correlation contributions.