%0 Journal Article
%A Seth, Priyanka
%A Peil, Oleg E.
%A Pourovskii, Leonid
%A Betzinger, Markus
%A Friedrich, Christoph
%A Parcollet, Olivier
%A Biermann, Silke
%A Aryasetiawan, Ferdi
%A Georges, Antoine
%T Renormalization of effective interactions in a negative charge transfer insulator
%J Physical review / B
%V 96
%N 20
%@ 2469-9950
%C Woodbury, NY
%I Inst.
%M FZJ-2017-08362
%P 205139
%D 2017
%X We compute from first principles the effective interaction parameters appropriate for a low-energy description of the rare-earth nickelate LuNiO3 involving the partially occupied eg states only. The calculation uses the constrained random-phase approximation and reveals that the effective on-site Coulomb repulsion is strongly reduced by screening effects involving the oxygen-p and nickel-t2g states. The long-range component of the effective low-energy interaction is also found to be sizable. As a result, the effective on-site interaction between parallel-spin electrons is reduced down to a small negative value. This validates effective low-energy theories of these materials that were proposed earlier. Electronic structure methods combined with dynamical mean-field theory are used to construct and solve an appropriate low-energy model and explore its phase diagram as a function of the on-site repulsion and Hund's coupling. For the calculated values of these effective interactions, we find that in agreement with experiments, LuNiO3 is a metal without disproportionation of the eg occupancy when considered in its orthorhombic structure, while the monoclinic phase is a disproportionated insulator.
%F PUB:(DE-HGF)16
%9 Journal Article
%U <Go to ISI:>//WOS:000415889800002
%R 10.1103/PhysRevB.96.205139
%U https://juser.fz-juelich.de/record/841270