The antiaromaticity of a series of dianions of p-substituted benzylidene dibenzo[a,d]cycloheptenes was examined through calculated measures of antiaromaticity. The nucleus-independent chemical shifts (NICS) and magnetic susceptibility exaltation both showed substantial antiaromatic character in the benzannulated tropylium anion. When the antiaromaticity was normalized for the area of the ring, ...

the density functional theory (dft) and the natural bond orbital (nbo) calculations basedmethod b3lyp/6-31g* were carried out to study the interaction of carbon nanotube (8,0) withnitrobenzene in two situations perpendicular and parallel. formation energies of compounds,charges, the highest occupied molecular orbital (homo) and the lowest unoccupied molecular'orbital (lumo) and the homo-lumo ba...

abstract: electrical sensitivity of a beryllium oxide nanotube (beont) was examined toward (c5h5n) molecule by using density functional theory (dft) calculations at the b3lyp/6-31(d) level, and it was found that the adsorption energy (ead) of pyridine on the pristine nanotubes is   a bout -73.29kcal/mol. but when nanotubes has been doped with s and p atomes , the adsorption energy changed . cal...

in this work, the effects of as-doped on the adsorption of oxygen gas on the outer and inner surface ofboron nitride nanotube (bnnts) is investigated. the structural parameters, quantum properties involving:bond length, bond angle, homo-lumo orbital, gapenergy, electron affinity, electronegativity, chemicalpotential, global hardness, global softness and nmr parameters of bnnts are calculated at...

Quantum mechanical calculations are performed on 116 conformers of the protein ubiquitin (Lange et al., Science 2008, 320, 1471–1475). The results indicate that the heat of formation (HOF), dipole moment, energy of the frontier orbitals HOMO and LUMO, and HOMO-LUMO gap fluctuate within their corresponding ranges. This study thus provides a link between the conformational dynamics of a protein a...

the density functional theory (dft) and the natural bond orbital (nbo) calculations basedmethod b3lyp/6-31g were carried out to study the interaction of dopamine with carbon nanotube.the nanotube used in this study, includes 60 c atoms (6, 6) type. relative and formation energies ofcompounds, muliken charges, occupancy, the highest occupied molecular orbital (homo) and thelowest unoccupied mole...

At the present theoretical study, DFT calculations were performed for elucidating thereaction, absorption energy and the quantum molecular descriptors including electronic chemical potential, chemical hardness, Homo, Lumo, band gap energy (Eg) and finding the most active nitrogen-doped graphene sheet (N-G) for absorption H2S, CH4, N2 and CO2 gases. Finally it found that nitrogen-doped gra...

In this paper and in order to guide the synthesis of novels materials with low band gaps, Theoretical study by using DFT method on six conjugated compound containing based on thiadiazolothienopyazine is reported. Different electron side groups were introduced to investigate their effects on the electronic structure. The theoretical knowledge of the HOMO and LUMO energy levels of the components ...

We investigate the electronic structure of the fullerenes encapsulated inside carbon nanotubes, the so-called nanopeapods, using the first-principles study. The orbital hybridization of LUMO+1 (the state above the lowest unoccupied molecular orbital) of C60, rather than LUMO as previously proposed, with the nanotube states explains the peak at approximately 1 eV in recent scanning-tunneling-spe...

The energy position of the lowest unoccupied molecular orbital (LUMO) in 3,4,9,10-perylene-tetracarboxylic dianhydride (PTCDA) and dimethyl-3,4,9,10-perylenetetracarboxilic diimide (DiMePTCDI) was determined by investigating the energy level alignment at molecular semiconductor/GaAs(100) interfaces. Interface dipoles are found to form at the interfaces of both organic materials and consequently...