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Analytical expressions for the charge-charge local-field factor and the exchange-correlation kernel of a two-dimensional electron gas

B. Davoudi·M. Polini·G. F. Giuliani·M. P. Tosi
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Abstract

We present an analytical expression for the static many-body local field factor $G_{+}(q)$ of a homogeneous two-dimensional electron gas, which reproduces Diffusion Monte Carlo data and embodies the exact asymptotic behaviors at both small and large wave number $q$. This allows us to also provide a closed-form expression for the exchange and correlation kernel $K_{xc}(r)$, which represents a key input for density functional studies of inhomogeneous systems.

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B. Davoudi, M. Polini, G. F. Giuliani, M. P. Tosi. 2001-06-10. Analytical expressions for the charge-charge local-field factor and the exchange-correlation kernel of a two-dimensional electron gas. https://doi.org/10.1103/physrevb.64.153101

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