Abstract We present an accurate first-principles study of the electronic structure and absorption spectrum six elemental metals (aluminium, gold, silver, copper, palladium, platinum) using density functional theory in all-electron full-potential framework. calculate dielectric function spectra plasma frequency, compare with experimental data obtained from photo-emission, absorption, electron en...

the oil-paper insulation is a type of an inexpensive combination insulation system in oil-filled power transformers. in this study the dielectric and strength properties of canola oil and mineral oil impregnated hand-sheet papers were investigated. all hand sheets were made of unbleached bagasse soda pulp with two different freeness levels of 200 ± 25 ml, csf and 400± 25 ml,csf. after drying th...

The electronic, and optical properties of rhombohedral Na0.5Bi0.5TiO3nanostructured thin film have been studied by the first–principle approach. Densityfunctional theory (DFT) has been employed to calculate the fundamental properties ofthe layers using full–potential linearized augmented plane–wave (FPLAPW) method. A2×2×1 supercell was constructed with two vacuum slabs o...

We calculate and model the microscopic dielectric response function for quantum dots using first principle methods. We find that the response is bulklike inside the quantum dots, and the reduction of the macroscopic dielectric constants is a surface effect. We present a model for the microscopic dielectric function which reproduces well the directly calculated results and can be used to solve t...

We systematically measure the dielectric function of atomically thin MoS2 films with different layer numbers and demonstrate that excitonic effects play a dominant role in the dielectric function when the films are less than 5-7 layers thick. The dielectric function shows an anomalous dependence on the layer number. It decreases with the layer number increasing when the films are less than 5-7 ...