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 are known to mispredict the Ga positional parameters. The extended AMF functional together with an onsite Coulomb interaction of U-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. (C) 2011 American Institute of Physics. [doi:10.1063/1.3599532]