We present a simple and efficient technique in ab initio electronic-structure calculation utilizing real-space double grid with high density of points the vicinity nuclei. This promises to greatly reduce overhead for performing integrals that involve nonlocal parts pseudopotentials, while keeping degree accuracy. Our procedure gives rise no Pulay forces, unlike other methods using adaptive coordinates. Moreover, we demonstrate potential power method by calculating several properties atoms molecules.

In this study, we present a theoretical and computational investigation of the atomic-scale structure heterointerface formed between (001) surface $L1_0$-ordered iron palladium (FePd) alloy graphene (Gr), namely, $L1_0$-FePd(001)/Gr. Using density functional theory (DFT) calculations, demonstrate that topmost layer consisting Pd (Pd-terminated surface) becomes more energetically stable than Fe, Pd-terminated surfaces are not conducive to Gr adsorption. On other hand, under oxygen atmosphere...

We present a set of efficient techniques in first-principles electronic-structure calculations utilizing the real-space finite-difference method. These greatly reduce overhead for performing integrals that involve norm-conserving pseudopotentials, solving Poisson equations, and treating models which have specific periodicities, while keeping high degree accuracy. Since methods are inherently local, they lot advantages applicability flexibility compared with conventional plane-wave approach...

Abstract In contrast to the current research on two-dimensional (2D) materials, which is mainly focused graphene and transition metal dichalcogenide-like structures, studies 2D oxides are rare. By using ab initio calculations along with Monte Carlo simulations nonequilibrium Green’s function method, we demonstrate that oxide monolayer (ML) of Cr 2 O 3 an ideal candidate for next-generation spintronics applications. has honeycomb-kagome lattice, where Dirac strongly correlated fermions...

The electron-conduction properties of fullerene-based nanostructures suspended between electrodes are examined by first-principles calculations based on the density functional theory. electron conductivity C60-dimer bridge is low owing to constraint junction molecules. When fullerenes doped electrons being inserted Li atoms into cages, unoccupied state around filled and can be significantly improved.

We have developed an efficient computational scheme utilizing the real-space finite-difference formalism and projector augmented-wave (PAW) method to perform precise first-principles electronic-structure simulations based on density-functional theory for systems containing transition metals with a modest effort. By combining advantages of time-saving double-grid technique Fourier-filtering procedure projectors pseudopotentials, we can overcome egg box effect in computations even first-row...

We present the evidence of low defect density at Ge/GeO$_2$ interfaces in terms first-principles total energy calculations. The advantages atom emission from interface to release stress due lattice mismatch are compared with those Si/SiO$_2$ interface. found be smaller than because high flexibility bonding networks GeO$_2$. Thus, suppression Ge-atom during oxidation process leads improved electrical properties interfaces.

Multishell helical gold nanowires (HGNs) suspended between semi-infinite electrodes are found to exhibit peculiar electron-conduction properties by first-principles calculations based on the density functional theory. Our results that numbers of conduction channels in HGNs and their conductances smaller than those expected from a single-atom row nanowire verify recent experiment. In addition, we obtained more striking result that, cases thin HGNs, distinct magnetic fields induced electronic...

Abstract Single‐molecule junctions exploit the internal structure of molecular orbitals to construct a new class functional quantum devices. The demonstration negative differential resistance (NDR) in single‐molecule is direct evidence mechanical tunneling through orbital. Here, pronounced NDR effect reported with peak‐to‐valley ratio 30.1 on junction π‐conjugated quinoidal‐fused oligosilole derivatives, Si2 × 2, embedded between unique electroless gold‐plated heteroepitaxial spherical Au/Pt...

We describe the anisotropic photoreaction of photoreactive side-chain liquid-crystalline polymers (SLCPs), containing biphenyl mesogen and cinnamoyl group, by irradiation with a linearly polarized (LP) UV light, alignment behavior low-molecular-weight (LMW) liquid crystal (LC) on them. The photo-crosslinked SLCP thin film photoreacted at room temperature showed very small negative dichroism, while that in LC range exhibited positive dichroism. can align LMW-LC director \tilde n both parallel...

Electron transport properties of C$_{20}$ molecules suspended between gold electrodes are investigated using first-principles calculations. Our study reveals that the conductances quite sensitive to number electrodes: monomers near 1 G$_{0}$, while those dimers markedly smaller, since incident electrons easily pass and predominantly scattered at C$_{20}$-C$_{20}$ junctions. Moreover, we find both channel currents locally circulating outermost carbon atoms.

We demonstrate an efficient nonequilibrium Green's function transport calculation procedure based on the real-space finite-difference method. The direct inversion of matrices for obtaining self-energy terms electrodes is computationally demanding in method because matrix dimension corresponds to number grid points unit cell electrodes, which much larger than that sites tight-binding approach. using ratio overbridging boundary-matching technique [Phys. Rev. B {\bf 67}, 195315 (2003)], related...

The relationship between the position of oxygen vacancies in HfO2/SiO2/Si gate stacks and leakage current is studied by first-principles electronic-structure electron-conduction calculations. We find that increase due to creation HfO2 layer much larger than SiO2 interlayer. According previous total energy calculations, formation smaller interlayer under same conditions. Therefore, will be attracted from minimize energy, thermodynamically justifying scavenging technique. Thus, process...

We present the first-principles study of coherent relationship between optimized geometry and conductance a three-aluminum-atom wire during its elongation. Our simulation employs optimum model including semi-infinite crystalline electrodes using overbridging boundary-matching method [Phys. Rev. B 67, 195315 (2003)] extended to incorporate nonlocal pseudopotentials. The results that is $\ensuremath{\sim}1\phantom{\rule{0.3em}{0ex}}{G}_{0}$ trace as function electrode spacing shows convex...

We investigate the effect of SiC stacking and interfacial O defects on electronic structure 4H-SiC/SiO2 interface via first-principles calculations. find interlayer states along conduction band edge, whose location changes depending which two possible lattice sites, h or k, is at interface. Excess atoms lead to defect structures alter structure. Changes valence edge are same whether k sites On other hand, remove state between first second bilayers if an site interface, but have no when there...

Density functional theory calculations are carried out to investigate the atomic and electronic structures of $4H\text{-SiC}(0001)/{\mathrm{SiO}}_{2}$ interface. We find two characteristic interface in scanning transmission electron microscopy images: One is an which density atoms at first interfacial SiC bilayer greater than that substrate, while other where lower. reveal difference images a reflection these interfaces. In addition, it has been reported floating states, appear conduction...

The relationship between the presence of defects at stacking structure $\text{Si}/{\text{SiO}}_{2}$ interface and leakage current is theoretically studied by first-principles calculation. I found that through with dangling bonds 530 times larger than without any defects, which expected to lead dielectric breakdown. direction closely related performance oxide as an insulator. In addition, it proved termination hydrogen atoms effective for reducing current.

The effect of SiO2 layers during the thermal oxidation a 4H-SiC(0001) substrate is examined by performing first-principles total-energy calculations. Although it expected that CO molecule most preferable product oxidation, CO2 molecules are mainly emitted from SiC surface at initial stage oxidation. As proceeds, emission becomes less favorable and interface. We conclude interface stress due to lattice constant mismatch between responsible for removal C resulting in characteristic electronic...

We carry out the direct minimization of energy functional proposed by Mauri, Galli, and Car [Phys. Rev. B $47,$ 9973 (1993)] to derive correct self-consistent ground-state solution Kohn-Sham equation. Since this method completely avoids instability caused level crossing, one can determine electronic structure metallic systems a high degree accuracy without aid broadening Fermi-distribution function. The efficiency is illustrated calculating ${\mathrm{C}}_{2}$ ${\mathrm{Si}}_{2}$ molecules...

In our previous work, we synthesized a metal/2D material heterointerface consisting of L10-ordered iron–palladium (FePd) and graphene (Gr) called FePd(001)/Gr. This system has been explored by both experimental measurements theoretical calculations. this study, focus on heterojunction composed FePd multilayer referred to as FePd(001)/m-Gr/FePd(001), where m represents the number layers. We perform first-principles calculations predict their spin-dependent transport properties. The...

We have investigated in detail the dependence of scanning tunneling microscopy (STM) images Si(001)-p(2×2) surface on bias and tip-sample distance, based first-principles molecular-dynamics simulations. STM terrace are found to be similar those at SA-step edges Si(001) surface. The present theoretical calculations predict that strongly depend sample separations, π π∗ states contribute changes corrugation images.

We present a first-principles study on the dielectric properties of an NaCl crystal and ultrathin films under finite external electric field. Our results show that high-frequency constant is not affected by size effect from surfaces close to crystal, whereas static one sensitive thickness film due difference in atomic configurations between surface inside film.

We present a first-principles study of the electron conduction properties single-row nanowires suspended between semi-infinite electrodes. The sodium exhibit conductance oscillation and bunching high density with two atom lengths in channel distribution. relationship period length bunches is interpreted using simplified model. difference penetration parameters incident Bloch wave reflected one inside nanowire closely related to bunches.