Self-healing mechanisms of vacancy defects in graphene and silicene are studied using first-principles calculations. We investigated host adatom adsorption, diffusion, formation, revealed atomistic the healing single, double, triple vacancies single-layer silicene. Silicon adatom, which is adsorbed to at top site forms a dumbbell-like structure by pushing one Si atom underneath. The asymmetric reconstruction single induced magnetization through rebonding two dangling bonds acquiring...

Using first-principles density functional theory calculations, we showed that electronic and magnetic properties of bare Ti adatom adsorbed single-layer silicene germanene, which are charged or subjected to a perpendicular electric field, can be modified attain new functionalities. In particular, when buckled atoms have the symmetry between their planes broken, opening gap at Dirac points. The occupation 3d orbitals atom changes with charging applied inducing significant in moment. We...

We present a first-principles study of various effects charging and electric field on the oxidation/deoxidation graphene oxide consisting only epoxy groups. first determined proper basis set, which hinders spurious spilling electrons when negatively charged or exerted by perpendicular field, treated with periodic boundary conditions. then showed that perpendicularly applied to surface provide side-specific functionalization. found bonds between oxygen are weakened under field. For specific...

We study the interaction of H$_2$, O$_2$, CO, H$_2$O and OH molecules with vacancy defects graphene silicene. Atoms around bare reconstruct specific chemically active sites are created. While O$_2$ CO remain intact on both pristine silicene, these can dissociate when they placed at close proximity nucleate centers for hydrogenation oxygenation. Saturation dangling bonds defect by constituent atoms dissociated gives rise to significant modification electronic magnetic properties. analyzed...

Graphene is a 2D material that has attracted much attention due to its outstanding properties. Because of high surface area and unique chemical physical properties, graphene good candidate for biological applications. For this reason, deep understanding the mechanism interaction with biomolecules required. In study, theoretical investigation van der Waals effects been conducted using density functional theory. Here we show order binding energies five nucleobases G > A T C U. This trend in...

We present a first-principles study of the effects charging and perpendicular electric fields on hydroxyl groups, both which mediate reduction graphene oxide through formation H2O H2O2. Starting with an investigation interaction between groups graphene, we determine equilibrium binding geometry, energy, diffusion path minimum energy barrier show that those properties are strongly affected by external agents. While co-adsorbed H O form bound OH, OH in close proximity almost no barrier. When...

Over the last decade, we have been witnessing rise of two-dimensional (2D) materials. Several 2D materials with outstanding properties theoretically predicted and experimentally synthesized. are good candidates for sensing detecting various biomolecules because their extraordinary properties, such as a high surface-to-volume ratio. Silicene germanene monolayer honeycomb structures silicon germanium, respectively. Quantum simulations very effective in understanding interaction mechanism may...

Dopamine (DA) is a crucial molecule for the central nervous system, and ability to detect it in samples containing molecules such as Ascorbic Acid (AA) Uric (UA) could facilitate early diagnosis of related disorders. In this work, interaction DA, UA, AA with InBi Graphene (GR) monolayers under charging was investigated using Density Functional Theory (DFT) calculations van der Waals (vdW) correction nonequilibrium Green’s function method first time. According our calculations, most...

Titanium atoms are adsorbed to graphene with a significant binding energy and render diverse functionalities it. Carrying out first-principles calculations, we investigated the effects of charging static electric field on physical chemical properties covered by Ti adatoms. When uniformly is charged positively, its antiferromagnetic ground state changes ferromagnetic metal attains permanent magnetic moment. Static applied perpendicularly causes charge transfer between graphene, can induce...

Semiconducting selenium and tellurium in their 3D bulk trigonal structures consist of parallel weakly interacting helical chains atoms display a number peculiarities. We predict that thermal excitations, 2D compressive strain excess charge positive negative polarity mediate metal-insulator transitions by transforming these semiconductors into different metallic crystal structures. When heated to high temperature, or compressed, charged positively, they change simple cubic structure with...

In this paper we investigated the interaction between a graphene nanoflake anchored to 2D monolayer. This is attractive but weak and capable of setting well defined registry in equilibrium. Rotational linear displacements from equilibrium generate restoring forces, which can be controlled by external agents. Similar flakes self-assembled also execute simple harmonic motion as if physical pendulum. Oscillation about their registries resulting characteristic libration frequency predicted....

Abstract We present a second nearest neighbor semi‐empirical sp 3 s * tight binding model to calculate the electronic band structure of nitride/arsenide or phosphide heterostructures. The Hamiltonian includes spin‐orbit coupling p‐states, (2NN) atomic interactions. Atomic energy levels and bond lengths ternary semi‐ conductors are taken as nonlinear function alloy com‐ position. findings for InAsN/InAs, GaPN/GaP GaAsN/GaAs structures in excellent agreement with experiment gaps at Γ, L X...

In this work, we present a first principles study of the adsorption Adenine which is nucleobases, Histide and Leucine molecules, are amino acids, on vacancy defected single layer materials such as graphene phosphorene. Among these materials, graphene, honeycomb structure carbon. Also, phosphorene recently synthesized by mechanical exfoliation black phosphorus. Phosphorene forming puckered similar to silicene. However, unlike zero-bandgap silicene, direct band gap semiconductor, makes it very...

After the discovery of Graphene, new two dimensional (2D) materials has been found out. Among them, Phosphorene, a significant advantage over semimetallic graphene and other typical 2D semiconductors. are also usually good candidates for gas sensors thanks to their large surface-to-volume ratio associated charge transfer between molecules substrates. Theoretical efforts have devoted study interactions this material with different molecules(CO, H2O, CH4 NH3). But such blue phosphorene lack....

We studied the electronic structure of group III-V nitride ternary/binary heterostructures by using a semi-empirical sp(3)s* tight binding theory, parametrized to provide accurate description both valence and conductions bands. It is shown that basis, along with second nearest neighbor (2NN) interactions, spin-orbit splitting cation anion atoms, nonlinear composition variations atomic energy levels bond length ternary, sufficient describe heterostructures. Comparison experiment shows theory...