Frequency-dependent local interactions and low-energy effective models from electronic structure calculations

Article

关键词: DENSITY-FUNCTIONAL CALCULATION;    RENORMALIZATION-GROUP METHOD;    RANDOM-PHASE-APPROXIMATION;    MEAN-FIELD THEORY;    GW METHOD;    SYSTEMS;    PARAMETERS;    SPECTRA;    NI;   

DOI  :  10.1103/PhysRevB.70.195104

来源: SCIE

【 摘 要 】

We propose a systematic procedure for constructing effective models of strongly correlated materials. The parameters, in particular the on-site screened Coulomb interaction U, are calculated from first principles, using the random-phase approximation. We derive an expression for the frequency-dependent U(omega) and show, for the case of nickel, that its high-frequency part has significant influence on the spectral functions. We propose a scheme for taking into account the energy dependence of U(omega), so that a model with an energy-independent local interaction can still be used for low-energy properties.

【 授权许可】

Free