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Systematic density functional theory (DFT) calculations have been performed to explore the interaction energetics, and electronic properties of Te8 cluster adsorbed on the h-BN surface. The interaction of Te8 cluster with BN sheet is due to weak Van-der-Waals forces at a distance of 4.33Å. The h-BN exhibits a wide band gap semiconducting nature with tuneability of band gap from 4.78 to 1.96 eV, with adsorption of Te8 cluster. HOMO-LUMO gap, density of states (DOS), projected density of states (PDOS) plots and electron charge density difference are also reported. [ABSTRACT FROM AUTHOR]

Using first principles density functional theoretical calculations, the present paper reports a systematic study of phonon dispersion curves in pristine carbon (CNT) and silicon nanotubes (SiNT) having chirality (6,6) in the armchair configuration . Some of the phonon modes are found to have negative frequencies which leads to instability of the systems under study. The number of phonon branches has been found to be thrice as much as the number of atoms. The frequency of the higher optical bands varies from 1690 to 1957 cm-1 for CNT(6,6) while it is 596 to 658 cm-1 for SiNT. [ABSTRACT FROM AUTHOR]

First principle calculations based on DFT have been performed to study the interaction of monoatomically thin Cu wire with silicon nanotube in armchair configuration having chirality (6, 6) both by placing it inside (encapsulation) and outside (functionalisation) the tube. The lowest energy for positioning monoatomically thin Cu wire inside and outside surfaces of SiNT were found to possess cohesive energies of 4.03 eV and 4.02 eV respectively and hence the stability of both SiNTs is found to be almost same. However, From the electronic band structures study, the conductance in case of SiNT for the encapsulated and functionalized positioning of the Cu wire have been found to be 2G0 and 4G0 respectively showing enhanced conductance for the functionalized SiNT. [ABSTRACT FROM AUTHOR]

First principle calculations based on density functional theory have been used to study the structural, electronic and optical properties of infinite armchair (6,6) silicon nanotube. The cohesive energy of the studied SiNT has been found to be 4.45 eV/atom in comparison to cohesive energy 5.22 eV/atom of its bulk counterpart. Contrary to some published results in literature, the SiNT with (6,6) chirality does not appear to have zero band gap semiconductor since it shows band gap of 0.18 eV. Also the absorption egde of SiNT shifts towards the lower energy as compared to bulk and lies in the infrared region, as a consequence of decrease in dimensionality. [ABSTRACT FROM AUTHOR]

We present first principal investigations on structural and electronic properties of in-plane phase engineered WSe2 with armchair type interface. The 2H and 1T phases of WSe2, joined along x-direction is a natural metal-semiconductor heterostructure and therefore shows potential for applications in 2D electronics and opto-electronics. The electronic properties transit towards metallic 1T region. No inflections across interface shows negligible mismatch strain which is unlike what has been reported for MoS2. Charge density analysis shows charge accumulation on 1T domain. This can lead to reduction of Schottky barrier heights at the metal-semiconductor junction. STM analysis confirms transition of 1T phase towards distorted 1T’ structure. The present results provide essential insights for nano-devices using 2D hybrid materials. [ABSTRACT FROM AUTHOR]