Trends of hybridization-induced magnetism in cerium monochalcogenides

A synthesis of ab initio linear-muffin-tin-orbital (LMTO) electronic structure calculations and a phenomenological model of orbitally .driven magnetic ordering has been applied to investigate trends of the effect of hybridization of moderately delocalized f electrons with band electrons on the diverse magnetic behavior across the cerium monochalcogenide series. The parameters entering the Anderson lattice model Hamiltonian are determined from total-energy supercell warped-muffin-tin LMTO calculations with zero, one, and two electrons in the cerium 4f core state. The origins, in the electronic structure, of the variation of the density of states at the Fermi energy, the f-state resonance width, the hybridization potential, the hybridization-dressed crystal-field splitting, and the hybridization-mediated exchange interactions with the chemical environment (anion size) on going down the chalcogen column have been investigated systematically, increasing thus the degree of f-electron localization as the cerium-cerium separation increases.