We examine the effects of vacancy defects on thermal conductivity in bulk crystalline silicon (c-Si) using nonequilibrium molecular dynamics simulations. While most vacancies are thought to remain in the form of clusters in bulk c-Si, recent theoretical studies have predicted that small vacancy clusters energetically prefer to be fourfold coordinated by nullifying dangling bonds. Hence, in this...

HRSEM analyses of copper/graphite interfaces are presented, showing a narrow solid solution zone. Atomistic simulations in the framework of the Generalized Simulated Annealing approach lead to very reasonable relaxed geometries around carbon interstitials and vacancy complexes of a Cu host, and for a Cu/graphite interface. Embedded Cluster Density Functional results indicate a charge transfer o...

1. Introduction The synthesis of nano–scale materials is a rapidly developing field of materials science. Recently, Sun et al. [1] have demonstrated the preparation of a number of hollow nanostructures of Au, Pd and Pt by a replacement reaction with Ag starting with solid Ag templates. Such structures have very considerable promise in a wide range of technological applications such as catalysis...

graphene sheet including single vacancy, double vacancy and stone-wales with armchair and zigzag structure was simulated using molecular dynamics simulation. the effect of defects on shear’s modulus, shear strength and fracture  strain was investigated. results showed that these shear properties reduce when the degrees of all kinds of defects increase. the dangling bond in sv and dv defected gr...

In this article, the important role of the intrinsic defects in size-controlled ZnO nanowires (NWs) which play a critical role in the properties of the NWs, was studied with a combined innovative experimental analysis. The NWs prepared by both the aqueous solution method and chemical vapour deposition process were of increasing length and decreasing size-to-volume (S/V) ratio. The combined appr...

ObjectivesA key criticism of applying the friction cost approach (FCA) to productivity estimation is its focus on a single period. A more accurate estimate worker absence requires consideration chain secondary vacancies arising from opening new primary vacancy. Currently, empirical evidence this almost absent. We suggest an original empirically costs that include vacancies.MethodsThe vacancy mu...

The oxygen vacancy-related polaron-like bound state migration in HfOx accounting for the observed transport properties in the high resistance state of resistive switching is investigated by the density functional theory with hybrid functional. The barrier of hopping among the threefold oxygen vacancies is strongly dependent on the direction of motion. Especially, the lowest barrier along the <0...

Within the framework of the GGA+U implementation of density functional theory, we investigate atomistic and electronic structures of Au adsorbed on the stoichiometric and the defective CeO(2){111} surfaces, in the latter of which either O or Ce vacancies are presented. We show that on the stoichiometric surface, the most stable adsorption site of Au is not on the top of the outermost O atoms, a...

As one of the most fascinating cathode candidates for Na-ion batteries (NIBs), P2-type Na layered oxides usually exhibit various single-phase domains accompanied by different Na+/vacancy-ordered superstructures, depending on the Na concentration when explored in a limited electrochemical window. Therefore, their Na+ kinetics and cycling stability at high rates are subjected to these superstruct...

Solid state lithium ion electrolytes are becoming increasingly important in batteries and related technologies. We have used first-principles modeling techniques based on density functional theory and the nudged elastic band method to examine possible Li ion diffusion mechanisms in idealized crystals of the electrolyte material Li3PO4. In modeling the Li ion vacancy diffusion, we find direct ho...