An ab initio method for calculating electron-phonon coupling parameters is presented. The method is an extension of the plane-wave-based linearresponse method for the calculation of lattice dynamics. Results for the mass enhancement parameter λ and the electron-phonon spectral function αF (ω) for Al, Pb and Li are presented. Comparisons are made to available experimental data. PACS numbers: 63....

pKa values are estimated independently, by two entirely different methods, for the ionizations of the apical and equatorial OH groups of two representative hydroxyphosphoranes. A bond length-pKa correlation based on crystal structures of cyclohexanol derivatives gives values of 13.5 +/- 1.5 and 8.62 +/- 1.87, respectively, for the apical and equatorial OH groups of tetracyclohexyloxyhydroxyphos...

The Peierls stress for a [111]-screw dislocation in bcc Tantalum is calculated using an embedded atom potential. More importantly, a method is presented which allows accurate calculations of the Peierls stress in the smallest periodic cells. This method can be easily applied to ab initio calculations, where only the smallest unit cells capable of containing a dislocation can be conviently used....

To reach the goal of prediction of electrochemical behavior from first principles, it appears increasingly evident that an intermediate stage, between ab initio calculation and Monte Carlo or classical molecular dynamics, will be required. Here we report progress on the development of such an intermediate computational method, using a self consistent tight binding approach, and report some prel...

We present approaches using stochastic processes for the calculation of line broadening in plasmas. The derivation of model microfield methods (MMM) based on analytic formulations is recalled, as well as an approach using a simulation of the stochastic process. We discuss the possibility of an improvement of the stochastic process by comparing our first results to ab initio particle simulations...

Species of arsenic and selenium thought to be present in coal combustion flue gases were studied using density functional theory and a broad range of ab initio methods. At each level of theory, the calculated geometries and vibrational frequencies of each species as well as the reaction enthalpies of anticipated reactions were compared with experimental data where available. Comparisons between...

We report the inclusion of electron-electron correlation in the calculation of transport properties within an ab initio scheme. A key step is the reformulation of Landauer's approach in terms of an effective transmittance for the interacting electron system. We apply this framework to analyze the effect of short-range interactions on Pt atomic wires and discuss the coherent and incoherent corre...

Lattice yield to tension within practical time and temperatures is determined by the probability of defect formation. Its rate in nanotubes depends in turn on the transition state and activation barrier for the Stone-Wales bond rotations. Systematic ab initio computations of the barriers for the tubes of various symmetries and radii led to accurate calculation of plastic yield strain as a funct...

An ab initio calculation of a secondary isotope effect on a bond length has been carried out for the first time. Single determinant molecular orbital computations indicate that the mean C-C bond length at O"K is longer in C,H6 than in C,D6 by 0.0015 A. A comparison with model calculations supports a steric interpretation in which H atoms act as if they are bulkier than 0 atoms owing to their la...

The Peierls stress for a [111]-screw dislocation in bcc Tantalum is calculated using an embedded atom potential. More importantly, a method is presented which allows accurate calculations of the Peierls stress in the smallest periodic cells. This method can be easily applied to ab initio calculations, where only the smallest unit cells capable of containing a dislocation can be conviently used....