Search

Incorporation of strong electron correlations into the density functional theory (DFT) for the electronic structure calculations of light lanthanides leads to a modification of interatomic forces and consequently the lattice dynamics. Using first-principles theory we demonstrate the substantial influence of the 4f electron correlations on the phonon dispersion relations of Nd. The calculations are verified by an inelastic x-ray scattering experiment performed on a single-crystalline Nd(0001) film. We show that very good agreement between the calculated and measured data is achieved when electron-electron interactions are treated by the DFT+U approach. [ABSTRACT FROM AUTHOR]

The phonon dispersion curves of the superconductor PuCoGa(5) were studied by inelastic x-ray scattering at room temperature. The experimental data agree well with ab initio lattice dynamics calculations. An accurate description of the phonon spectrum is obtained only when a local Coulomb repulsion U approximately equal 3 eV among 5f electrons is taken into account.