A tight-binding procedure is presented for fitting electronic band structures of crystals. It is based on a fully automated method of determining all possible independent matrix elements for arbitrary crystal structures. A fit, using this method, for the band structure of hexagonal close-packed Tc is more than an order of magnitude better than previous fits. A practical procedure for optimizing...

We report a hybrid approach for photonic systems that combines chemically synthesized single nanowire emitters with lithographically defined photonic crystal and racetrack microresonator structures. Finite-difference time-domain calculations were used to design nanowire photonic crystal structures where the photonic band gap overlaps the electronic band gap of the nanowire. Photoluminescence (P...

A general method is presented to unfold band structures of first-principles supercell calculations with proper spectral weight, allowing easier visualization of the electronic structure and the degree of broken translational symmetry. The resulting unfolded band structures contain additional rich information from the Kohn-Sham orbitals, and absorb the structure factor that makes them ideal for ...

Adsorption of NO2 molecule on pristine and N-doped TiO2 anatase nanoparticles have been studied using the density functional theory (DFT) technique. The structural properties (such as bond lengths and bond angles) and the electronic properties (such as density of states, band structures and atomic partial charges) have been computed for considered nanoparticles. The result...

Silicon is the most popular material used in electronic devices. However, its poor optical properties owing to its indirect band gap nature limit its usage in optoelectronic devices. Here we present the discovery of super-stable pure-silicon superlattice structures that can serve as promising materials for solar cell applications and can lead to the realization of pure Si-based optoelectronic d...

Ground-state structures and other experimentally relevant isomers of Au(15) (-) to Au(24) (-) clusters are determined through joint first-principles density functional theory and photoelectron spectroscopy measurements. Subsequent calculations of molecular O(2) adsorption to the optimal cluster structures reveal a size-dependent reactivity pattern that agrees well with earlier experiments. A de...

Magnetically driven actuator materials, such as the ternary and intermetallic Heusler alloys with composition X2YM, are studied within the density-functional theory (DFT) with the generalized gradient approximation (GGA) for the electronic exchange and correlation. The geometrical and electronic structures for the magnetic L21 structure are calculated. The structures and magnetic moments at equ...

ZnO/GaN alloys have exceptional photocatalytic applications owing to their suitable band gaps corresponding to the range of visible light wavelength and thus have attracted extensive attention over the past few years. In this study, the structural stabilities and electronic properties of core/shell, biaxial, and super-lattice ZnO/GaN heterostructured nanowires have been investigated by means of...

In this work we investigate the thermal conductivity of graphene-based antidot lattices. A third nearest-neighbor tight-binding model and a forth nearest-neighbor force constant model are employed to study the electronic and phononic band structures of graphene-based antidot lattices. Ballistic transport models are used to evaluate the electronic and the thermal conductivities. Methods to reduc...

Density functional theory was used to performed a survey of transition metal oxide (MO2 = ZrO2, HfO2) ordered molecular adsorbate bonding configurations on the Ge(100)-4 2 surface. Surface binding geometries of metal-down (O–M–Ge) and oxygen-down (M– O–Ge) were considered, including both adsorbate and displacement geometries of M–O–Ge. Calculated enthalpies of adsorption show that bonding geome...