Showing papers by "Paolo Giannozzi published in 1987"
TL;DR: Proposition d'une nouvelle methode, basee sur the theorie des perturbations dans laquelle la reponse au potentiel total est obtenue par iteration jusqu'a l'autocoherence, la sommation sur les bandes de conduction evitee grâce a une technique a fonction de Green.
Abstract: We present a new scheme to study the linear response of crystals which combines the advantages of the dielectric-matrix and supercell (``direct'') approaches yet avoids many of their drawbacks. The numerical complexity of the algorithm is of the same order as that of a self-consistent calculation for the unperturbed system. The method is not restricted to local perturbations as the dielectric-matrix one nor to short wavelengths as the direct one. As an application, we calculate the long-wavelength optical phonons in Si and GaAs, both transverse and longitudinal, using norm-conserving pseudopotentials, and without any use of supercells.
1,532 citations
TL;DR: In this article, the elastic constants of solids are given directly by a single self-consistent calculation (i.e., they are not obtained by numerical differentiation of total energies or stresses).
Abstract: We propose a new scheme to calculate the elastic constants of solids which is based on linear-response theory. Elastic constants are given directly by a single self-consistent calculation (i.e., they are not obtained by numerical differentiation of total energies or stresses). As an illustration, we apply our procedure to the determination of the equilibrium lattice constant, bulk modulus, and pressure derivative of the bulk modulus of silicon.
74 citations
TL;DR: In this paper, the magnetic properties of UO2 are reexamined by taking into account the recent observation of a 3-k structure in the ordered phase, based on effective quadrupole-quadrupole interaction mediated by virtual optical phonons.
33 citations
8 citations