In this work, we have calculated ab initio the equation of state, the principal phonon modes, the effective charges and the temperature dependence of the specific heat for the III-Nitrides, by using the density-functional theory within the local density approximation, plane wave expansions and the pseudopotential method. A good agreement with the experiment and other calculations is obtained, w...

We reformulate the strong-interaction limit of electronic density functional theory in terms of a classical problem with a degenerate minimum. This allows us to clarify many aspects of this limit, and to write a general solution, which is explicitly calculated for spherical densities. We then compare our results with previous approximate solutions and discuss the implications for density-functi...

The screening of a He+ ion embedded in a paramagnetic electron gas is studied using density functional theory within the local spin density approximation. We calculate the induced electron density and the induced density of states for each spin orientation, parallel and antiparallel to that of the electron bound to the He+ ion. Our results show that the screening is preferably due to parallel s...

The electronic structure of V2O3 thin films is studied by means of the augmented spherical wave method as based on density functional theory and the local density approximation. We establish that the effects of charge redistribution, induced by the vacuum interface, in such films are restricted to a very narrow surface layer of ≈15Å thickness. As a consequence, charge redistribution can be rule...

We report the results of a comprehensive study on the structural, electronic, and optical properties of Ga2O3 in its ambient, monoclinic and high-pressure, hexagonal phases in the framework of all-electron density functional theory. In both phases, the conduction band minimum is at the zone center while the valance band maximum is rather flat in the k space. The calculated electron effective ma...

In this work, by using the density-functional theory within the local density approximation, plane wave expansions and the pseudopotential method, we present our preliminary results for the strain-induced shifts of the zone center phonon modes and of the effective charges on the III-Nitrides. Our results are in good agreement with the experiment as well as with other calculations, whenever a co...

The purpose of this short essay is to introduce students and other newcomers to the basic ideas and uses of modern electronic density functional theory, including what kinds of approximations are in current use, and how well they work (or not). The complete newcomer should find it orients them well, while even longtime users and aficionados might find something new outside their area. Important...

The reactivity between lithium and the Al13 cluster is studied using the density functional theory and the local density approximation (LDA) for exchange and correlation. The effects caused by the addition of two Li atoms on the structural and electronic properties of the Al cluster are analyzed by calculating equilibrium geometries, binding energies and ionization potentials. The corresponding...