A Quantum Chemistry Plus Dynamical Mean Field Approach for Correlated Insulators: Application to La₂CuO₄

الأصل · EN

While the traditional local-density approximation (LDA) cannot describe Mott insulators, ab-initio determination of the Hubbard U, for example, limits LDA-plus dynamical mean field theory (DMFT) approaches. Here, we attempt to overcome these bottlenecks by achieving fusion of the quantum chemistry (QC) approach with DMFT. QC+DMFT supplants the LDA bandstructure by its QC counterpart as an input to DMFT. Using QC+DMFT, we show that undoped La₂CuO₄ is a d-Mott insulator, and qualitatively discuss the circulating current- and incoherent metal phase, at small but finite hole doping. Very good quantitative agreement with experimental photoemission- and optical spectra constitutes strong support for efficacy of QC+DMFT. Our work thus opens a new avenue for truly ab-initio correlation-based approaches to describe correlated electronic systems in general.