The geometries of a series of nine 4-substituted nitrophenols and 4-substituted nitrophenolates (X = H, CONH2, CHO, COOH, COCH3, COCl, CN, NO2, NO) and of their conformers, where the nitro group rotates by 10o from  = 0° to  = 90°, were optimized at the B3LYP/6-311+G** DFT level. These data were used to analyse the effect of rotating of the nitro group on -electron delocalization in the ring...

The conformations of a series of benziporphyrins, naphthiporphyrins, oxybenziporphyrins, and related structures were minimized using DFT-B3LYP/6-311++G(d,p). The relative stabilities of the tautomers for each series were calculated using M06-2X and B3LYP-D functionals, and bond lengths were obtained. The diatropic properties of each species were assessed by calculating nucleus independent chemi...

We have studied the topological and local aromaticity of BN-substituted benzene, pyrene, chrysene, triphenylene and tetracene molecules. The nucleus-independent chemical shielding (NICS), harmonic oscillator model of aromaticity (HOMA), para-delocalization index (PDI) and aromatic fluctuation index (FLU) have been calculated to quantify aromaticity in terms of magnetic and structural criteria. ...

The synthesis of heteroatom analogues of the cyclopentadienyl anion Cp- is a fascinating and challenging field of research. The replacement of methine moieties by phosphorus is well investigated for the synthesis of mono-, tri- and pentaphospholyl ligands. On the other hand, arsenic derivatives are rare and 1,2,4-triarsolyl and tetraarsolyl salts are unknown. Herein, we report on the synthesis ...

In this study, B12N12 Nano ring has been selected because it consist of four 6-side rings and polar bonds B-N which in comparison with non-polar bonds C-C, is more suitable for the study of the absorption of other compounds. So reactivity and stability of Benzene alone and in the presence B12N12 nano ring field checked. To determine the non-bonded interaction energies between Benzene and B12N12...

NICS methodology has been applied to study the change in aromaticity in several aromatic rings (benzene, pyrrol, triazine, hexafluorobenzene) on complexation with several ions (Li, Na, K. F, Cl). For this purpose all the isolated and complexed rings have been optimized at the MP2/6-31++G(d,p) level of theory. Using GIAO method to calculate NICS values, the change in aromaticity on complexation ...

The spin blocker capacity of borazine is investigated. Specifically, meta-B-B, meta-N-N and para-B-N connected borazines are used as spin-blocker couplers comprised of a pair of radicals: two iminonitroxides (IN); IN and tetrathiafulvalene radical cations (TTF); or two TTFs. Density functional theory (DFT) is used to elucidate the spin blocker capacity of the linkage-specific (meta or para) bor...

Electronic structure calculations (B3LYP/6-311+G**) predict that nucleophilic attack of the aromatic cycloCu4(μ)4 ring yields ligand-stabilized tetranuclear Cu4 clusters formulated as cyclo-Cu4(μ)4Nucn (n = 1-4; Nuc = N2, CO, H2O, NH3 and PH3). Depending on the number of added nucleophiles, the tetranuclear Cu4 clusters adopt planar, bent or 3D tetrahedral geometries. These molecules exhibit ar...

Octachloronaphthalene (OCN), a serious environmental pollutant, has been investigated by charge density analysis to unravel several unexplored factors responsible for steric overcrowding. The topological features of the enigmatic peri interactions contributing to steric overcrowding are qualified and quantified from experimental and theoretical charge-density studies. A new facet in the fundame...

Prior to installation of a large harmonic load it is necessary to conduct a harmonic analysis using computer simulation in order to pr"iirt possible negative effects of harmonics' The 'problem is that many parameters are unknown and need to be assumed. One of these are existing or background harmonic levels. Tthe paper describes the resubs of harmonic measurements as Qn inclication of existing ...