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تسجيل مستخدم جديدAb initio many-body GW correlations in the electronic structure of LaNiO$_2$
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We present an ab initio $GW$ self-energy calculation of the electronic structure of LaNiO$_2$. With respect to density-functional theory we find that in $GW$ the La 4$f$ states undergo an important $+$2 eV upward shift from the Fermi level, while the O 2$p$ states are pulled down by $-$1.5 eV, thus reinforcing the charge-transfer character of this material. However, $GW$ many-body effects leave the $d$-like bands at the Fermi level almost unaffected, so that the Fermi-surface topology is preserved, unlike in cuprates.
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