The crystal structure of o-toluidinium chloranilate and m-toluidinium chloranilate, 2CH3C6H4NH3 · C6O4Cl22−, was determined by single crystal X-ray diffraction at room temperature. It was found that o-toluidinium chloranilate (I) is monoclinic, P21/n (#14), Z = 2, a = 5.2184(14), b = 7.825(2), c = 22.840(5) Å, and β = 92.015(19)◦ , and m-toluidinium chloranilate (II) is monoclinic, P21/c (#14),...

The structural saturation and stability, the energy gap, and the density of states of a series of small, siliconbased clusters have been studied by means of the PM3 and some ab initio ~HF/6-31G* and 6-31111G**, CIS/6-31G* and MP2/6-31G*! calculations. It is shown that in order to maintain a stable nanometric and tetrahedral silicon crystallite and remove the gap states, the saturation atom or s...

Abstract High-resolution (600 MHz) 1H and 13C chemical shift 2D HETCOR NMR spectra of [60]PCBM were recorded. Resonances from every carbon atom the ester, phenyl cyclo-fullerenyl groups, fully accounted. Assignments fullerene cyclopropa-ring, all ester carbons to their respective resonances based on a spectrum. Remaining assignments made high level confidence with aid an ωB97X hybrid HF/DFT sim...

In this study the hardness SWCT was calculated with B3LYP,HF method and 3-21G,6-31G,6-311G basis set .Then it was investigated with the best method(B3LYP) and basis set(6-31G) to study the adsorption effects CO2 on the hardness of SWCNT with gap HOMO-LUMO in two shape: Horizontal, Vertical and Top-Center-Bridge and We also provide the effects of CO2 adsorption on the elect...

The combination of Quantum Mechanics (QM) and Molecular Mechanics (MM) methods hasbecome alternative tool for many applications that pure QM and MM could not be suitable.The QM/MM method has been used for different type of problems, for example: structuralbiology, surface phenomena, and liquid phase. In this paper we have performed these methods forsome antibiotics and vitamins and then we comp...

In this paper, the quantum chemistry calculations related to the structural parameter of the three anions and the resulting complexes with glycine and alanine have been performed. The calculations were carried out using the HF and DFT method and in the base series 6-31G *. Natural Transplantation Orbital (NBO), hybrid capacity for bindings and is obtained. The ratio of the internal electrons, V...

Relative stabilities of rotamers of the N-acetyl-O-(2-acetamido-2-deoxy-alpha-D-galactopyranosyl)-L-seryl-N'-methyl amide (1) and eleven analogous molecules containing beta-galactose, alpha- and beta-mannose, alpha- and beta-glucose, and L-threonine were calculated to learn whether they could explain the natural preference for 1 in linkages between the carbohydrate and protein in glycoproteins....

Through-space isotropic NMR shielding values of a perpendicular diatomic hydrogen probe moved in a 0.5 Å grid 2.5 Å above several polycyclic aromatic/antiaromatic ring and aromatic/aromatic hydrocarbons were computed with Gaussian 03 at the GIAO HF/6-31G(d,p) level. Combinations of benzene fused with cyclobutadiene, with the tropylium ion, and with the cyclopentadienyl anion were investigated. ...