A plane-wave semiempirical pseudopotential method with nonlocal potentials and spin-orbit coupling is used to calculate the electronic structure of surface-passivated wurtzite CdSe quantum dots with up to 1000 atoms. The calculated optical absorption spectrum reproduces the features of the experimental results and the exciton energies agree to within ;0.1 eV over a range of dot sizes. The corre...

Determining excited state properties of atomic clusters is a challenging problem. In general, the ground state structural properties of clusters are unknown and not subject to direct experimental probes. Without knowledge of these properties, it is not possible to predict accurate optical excitations in clusters. Here we present a real-space-pseudopotential method to determine the structural pr...

We present pseudopotential coefficients for the first two rows of the Periodic Table. The pseudopotential is of an analytic form that gives optimal efficiency in numerical calculations using plane waves as a basis set. At most, seven coefficients are necessary to specify its analytic form. It is separable and has optimal decay properties in both real and Fourier space. Because of this property,...

The high pressure behavior of the structural and electronic properties of KC1 is studied with use of the density functional pseudopotential method within local-density approximation. Atzero pressure, the rocksalt phase is found to be lower in energy than CsCl structure. However, we predict a phase transition into CsCI structure at a pressure of about 1.5 GPa. The calculated ground state pro...

We have studied the diamond to -tin phase transition in Si using diffusion quantum Monte Carlo DMC methods. Slater-Jastrow-backflow trial wave functions give lower DMC energies than Slater-Jastrow ones, and backflow slightly favors the -tin phase with respect to the diamond phase. We have investigated the changes in the equation of state that result from the use of different pseudopotentials, t...

We present a joint implementation of dynamical-mean-field theory (DMFT) with the pseudopotential plane-wave approach, via Wannier functions, for the determination of the electronic properties of strongly correlated materials. The scheme uses, as input for the DMFT calculations, a tight-binding Hamiltonian obtained from the planewave calculations by projecting onto atomic-centered symmetry-const...

2014 The electronic band structure of magnesium fluoride is calculated by a combined tight binding and pseudopotential method in order to interpret the numerous experimental data. The gap anisotropy is clearly shown and the values of parallel and perpendicular gaps are in good agreement with the measured ones. A tentative interpretation of some other experimental transitions is given. LE JOURNA...