Excitation spectra of the Ce monopnictides within dynamical mean-field theory

The excitation spectra of the Ce monopnictides CeN, CeP, and CeAs are calcu lated using a lattice tight binding model including the local Coulomb repul sion U on the Ce 4f orbitals. The model is treated within the dynamical mea n-field theory, whereby the problem is mapped onto an effective Anderson im purity model. This is solved in a finite-Li extension of the noncrossing ap proximation, including lowest-order crossing diagrams. The lattice model is parametrized by means of ab initio calculations. The calculated spectra ar e in good agreement with experiment. In particular, dispersive quasiparticl e peak positions are found close to the Fermi edge in CeP. CeN shows metall ic Fermi-liquid behavior with a correlation-induced mass enhancement factor of similar to 5 around the Fermi level. [S0163-1829(98)09843-9].