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P. Roura-Bas V. Vildosola A. M. Llois

Publications and source records attributed to P. Roura-Bas V. Vildosola A. M. Llois.

2 recordsLinked to original sources

Evolution of the crystal-field splittings in the compounds CeX (X=P, As, Sb, Bi), \\CeY (Y=S, Se, Te) and their alloys CeX$_{1-x}$Y$_{x}$}

The crystal-field splittings of the monopnictides and monochalcogenides of Cerium (CeX and CeY) and their alloys (CeX$_{1-x}$Y$_x$) are calculated by means of an \emph{ab initio} many-body combined technique. The hybridization functions of the 4f states of Cerium with the conduction band for each material are obtained from first principles within the local density approximation (LDA) and are used as input for the Anderson impurity model, which is solved within a multi-orbital Non-Crossing Approximation (NCA). This realistic theoretical approach (LDA-NCA) is able to reproduce the experimental results for the crystal-field splittings of the CeX and CeY series in agreement with previous theoretical calculations. It is also able to describe the non-linear evolution of the splittings in the CeX$_{1-x}$Y$_x$ alloys as a function of x. An analysis of the values of the crystal-field splittings in all the compounds can be done in depth in this contribution, due to a detailed knowledge of the band structure and crystal environment in combination with many-body physics.

cond-mat.str-el↗

Hybridization functions of intermetallic Ce compounds with group VI elements

Among the Cerium compounds, the heavier monochalcogenides CeY (Y=S,Se,Te) of cerium provide a class of compounds which together with the heavier monopnictides CeX (X=N,P,As,Sb,Bi) exhibit extremely interesting physical properties. The hybridization of the partially delocalized f-electrons seems to be responsible for the unusual properties, in particular the magnetic ones which show great chemical sensitivity. As compared to the monopnictides, the monochalcogenides have an additional anion p-electron which shifts the Fermi energy into the p-region of the Cerium 5d-derived density of states, and which should affect the hybridization function of the electrons in the conduction band. In this contribution we analyze the 4f-hybridization function and the crystal-field splittings of the compounds under study. KEY WORDS: Highly correlated systems, crystal fields, p-electron.

cond-mat.str-el↗