Evolution of correlated electrons in La3Ni2O7 at ambient pressure: a study of double-counting effect

We employ cluster extension of dynamical mean-field theory (CDMFT) to systematically investigate the impact of double counting corrections on the correlated electronic structure of La 3 Ni 2 O 7 under ambient pressure. By adjusting double-counting parameters, while maintaining a fixed Fermi surface, we observe a pronounced orbital-selective density of states change: the dz² d z 2 orbital undergoes significant variation near the Fermi level with increasing Edcᶻ E dc z , while the dx²-y² d x 2 - y 2 orbital remains essentially unchanged throughout the entire range. Analysis of renormalization factor show the monotonic dependence with double counting in both dz² d z 2 and dx²-y² d x 2 - y 2 orbital, and it also identifies an optimal double counting window in dz² d z 2 orbital aligns with experimental values. We also find the interlayer Matsubara self energy exhibits non-monotonic dependence on Edcᶻ E dc z , deviating from theoretical predictions. This anomaly is attributed to the metallization of oxygen-bridged pathways, which disrupts the prerequisite for charge transfer via apical oxygen. Our results establish Edc E dc as a critical control parameter for correlated electronic structure in La 3 Ni 2 O 7 and provide a computational framework for resolving orbital-dependent correlation effects in layered materials.