The electronic and optical properties of polythiophene (PT) for polymer light-emitting diodes (PLEDs) were calculated using density functional theory (DFT) time-dependent DFT. We the thiophene PT polymers with degrees polymerization (DP) from 2 to 30 monomers (T1–T30) their derivatives. associated highest occupied molecular orbital (HOMO) energy, lowest unoccupied (LUMO) band gaps, electron orb...

All-electron static and time-dependent DFT electronic calculations, with complete geometrical optimization, are performed on tubular molecules up to C(210)H(20) that are finite sections of the (5,5) metallic single wall carbon nanotube with hydrogen termination at the open ends. We find pronounced C-C bond reconstruction at the tube ends; this initiates bond alternation that propagates into the...

A new chiral perylene monoanhydride monoimide (1) with a sterically hindered chiral amine was successfully synthesized for further selective functionalization at terminal positions. At the same time, the chiral perylene diimide (2) with the same amine has been synthesized. The synthesized products were characterized using the data from NMR, IR, MS, UV-vis, DSC, TGA, elemental analysis and cycli...

We studied the adsorption of 4,4'-dithiodipyridine (PySSPy) on Au(111) under ultra-high vacuum conditions and at low-temperature both experimentally by means of scanning tunneling microscopy and spectroscopy (STM and STS), and theoretically by density functional theory (DFT). We find PySSPy molecules – characterized by their elongated appearance in STM – assembled in islands which reside exclus...

We report the results of a theoretical study of sequential oxidation of gallium oxide clusters from Ga3O4 to Ga3O8. These results, based on density functional theory calculations, find the ground state of the neutral clusters to be in the lowest spin state with nearly the same binding energy of 3.5 eV per atom. Electron affinity, ionization potential and HOMO–LUMO gap values of these oxygen-ric...

A recent improvement in the design of dyesensitized solar cells has been the combination of lightabsorbing, electron-donating, and electron-withdrawing groups within the same sensitizer molecule. This dye architecture has proven to increase the energy conversion efficiency of the cells, leading to record efficiency values. Here we investigate a zinc(II)-porphyrin-based dye with triphenylamine d...

Bacteriochlorophylls (BChls) play an important role as light harvesters in photosynthetic bacteria. Interestingly, bacteriochlorophylls (BChls) a, b, and g selectively tune their visible (Qx) and near IR (Qy) absorption bands by the substituent changes. In this paper, we theoretically study the mechanism for the selective control of the absorption bands. Density functional theory (DFT) and time...

Chemical stabilities of six low-energy isomers of C24 derived from global-minimum search are investigated. The six isomers include one classical fullerene (isomer 1) whose cage is composed of only five- and six-membered rings (56-MRs), three nonclassical fullerene structures whose cages contain at least one four-membered ring (4-MR), one plate, and one monocyclic ring. Chemical and electronic p...

In this research, the interactions of HCN gas with pristine, Ga-, N- and GaN-doped of boron phosphide nanotube (BPNTs) were investigated by using density function theory (DFT). The structure, electrical and NQR parameters, quantum descriptors involving energy gap, global hardness, global softness, electrophilicity, electronic chemical potential and electronegativity were calculated. The adsorpt...