DFT – Page 3 – TechConnect Briefs

Study of the ferroelectric properties for PVDF using DFT Theory

Ortíz E., Cuán A., Badillo C., Wang Q., Noreña L., Universidad Autonoma Metropolitana-Azcapotzalco, MX

Polyvinylidene fluoride (PVDF) exhibits piezoelectricity effect. In this work, it is presented a theoretical study of some properties of this material which were calculated by Density Functional Theory (DFT). Among those properties are: polarizability, dipolar [...]

An Embedded Atom Method for Alloy Nanoparticles

Shan B., Hyun J., Wang L., Yang S., Kapur N., Nicholas J.B., Nanostellar Inc., US

We present the development and application of a high-accuracy embedded atom method (EAM) potential for the simulation of metal alloy nanoparticles. The potential was parametrized by a large set of density functional theory (DFT) calculations [...]

Electronic structure of single wall carbon nanotubes under transverse external electric fields, radial deformations and defects

Shtogun Y.V., Woods L.M., University of South Florida, US

Our tight-binding results show that energy gap modulations of radially deformed carbon nanotubes by external electric field can be achieved using various field amplitudes and field orientations, and deformation strengths, thus proving many more capabilities [...]

The binding site interactions between 7-chloro-tetracycline and the Tet Repressor

de Bruin P.H.S., Flores M.Z.S., Caetano E.W.S., Cavada B.S., Freire V.N., Universidade Federal do Ceará, BR

Tetracyclines are a class of broad spectrum antibiotics whose use has been limited by the emergence of bacterial resistance. The most common mechanism of resistance is regulated by the repressor protein, TetR. The structure of [...]

Dielectric Response in Silicon Nanostructures from first principles

Hamel S., Williamson A., Wilson H., Gygi F., Galli G., Ratner E., Wack D., Lawrence Livermore National Laboratory, US

In the next few years, the typical size of finFET devices used in the microchip industry is expected to be of the order of a few nanometers. This poses formidable challenges, including for optical metrology, [...]

Conduction Properties of BN-doped Fullerene Chain Obtained by Density Functional Calculations

Krainara N., Luksirikul P., Sirijaraensre J., Pantu P., Limtrakul J., Kasetsart University, TH

Carbon-based molecules such as fullerenes and carbon nanotubes, have attracted the attention of researchers because of their unique mechanical, and electronic properties and potential applications in a wide variety of areas of nanotechnology. The substitution [...]

Scanning Tunneling Microscopy Images of Au Adsorbed on GaAs(111)B surface

Yi H., Kratzer P., Hilner E., Mikkelsen A., KISTI, KR

We have studied the GaAs(111)B surface with Au deposited either homogeneously or as nanoparticles, and found the presence of Au in either form to give rise to a $(sqrt{3} !times! sqrt{3} )$ Au-induced surface reconstruction. [...]

Structure and Electronic Properties of “DNA-Gold-Nanotube” Systems: A Quantum Chemical Analysis

Pannopard P., Sirijaraensre J., Nokbin S., Khongpracha P., Limtrakul J., Kasetsart University, TH

The idea of chemical sensing based on molecular recognition is known as one of the most promising concepts for single-molecule detection, even though it still remains in an early developmental stage. The approach requires probes [...]

Ab initio calculation of tunneling current through ultra-thin SiO2 gate dielectric of MOS Structure, including the influence of oxygen vacancies on the tunneling current

Nadimi E., Janisch R., Radehaus C., TU Chemnitz, DE

We used a first-principle atomistic scale method, based on density functional theory and non-equilibrium Green’s function to study the electron tunneling current through ultra thin silicon oxide films. The Si/SiO2 model interface has been constructed [...]

Wall Functions for Incorporation of Atomistic Physics into Continuum Modeling of Electrokinetic Flow

Nilson R.H., Griffiths S.K., Sandia National Laboratories, US

The atomistic physics of fluid/solid interfacial layers may substantially influence liquid flow and ion transport, particularly in nanoscale channels. Previous studies addressing non-continuum fluid mechanics have been largely based on Molecular Dynamics (MD) simulations that [...]