Role of electronic correlations in Ga

Zhiyong Zhu; Xuhui Wang; Udo Schwingenschlögl

doi:10.1063/1.3599532

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arXiv · 1111.1895

Role of electronic correlations in Ga

Zhiyong Zhu·Xuhui Wang·Udo Schwingenschlögl

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Abstract

An extended around mean field (AMF) functional for less localized $p$ electrons is developed to quantify the influence of electronic correlations in $\alpha$-Ga. Both the local density approximation (LDA) and generalized gradient approximation (GGA) are known to mispredict the Ga positional parameters. The extended AMF functional together with an onsite Coulomb interaction of $U_{\rm eff}=1.1$ eV, as obtained from constraint LDA calculations, reduces the deviations by about 20%. The symmetry lowering coming along with the electronic correlations turns out to be in line with the Ga phase diagram.

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Zhiyong Zhu, Xuhui Wang, Udo Schwingenschlögl. 2011-11-08. Role of electronic correlations in Ga. https://doi.org/10.1063/1.3599532

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