We have evaluated the NMR shielding tensors for A:T,G:C,A:U in Watson-crick, and U-quartet. We have computed NMR shielding tensors at B31YP level by using 6-31G(d) basis set. We have compute anisotropy and asymmetry in A:T,G:C,A:U and U-quartet. The NMR shielding tensors were calculated using the GIAO method. The natural bonding orbital analysis (NBO) were performed. NBO calculation have been ...

In this research work at The first compounds [C60- 2-(naftalin-1-ilmetil)-4,5-dihidro-1H-imidazol-C65-2X]+ (X=F,Cl,Br) were optimized. Then the calculation of natural bond orbitals was performed with the NBO technique. All calculations using Hartree- fock  the 6-31G * basis set using Gaussian 98 software and in gas phase has been done. The results showed that the energy levels of mol...

The complexes formed by H2CO, CH3CHO, and (CH3)2CO with 1, 2, and 3 molecules of CO2 are studied by ab initio calculations. Three different types of heterodimers are observed, most containing a tetrel bond to the C atom of CO2, and some supplemented by a CH⋅⋅O H-bond. One type of heterodimer is stabilized by an anti-parallel arrangement of the C=O bonds of the two molecules. The binding energie...

Vibrational Spectroscopic, Electronic Structure, Natural Bond Orbital Analysis and Quantum Chemical Investigations of 4-Methoxy-4-Methyl2-Pentanone A JAYAPRAKASH*1, V ARJUNAN2 and S MOHAN3 1Department of Physics, Rajiv Gandhi College of Engineering and Technology, Puducherry 607 402, India 2Department of Chemistry, Kanchi Mamunivar Centre for Post-Graduate Studies, Puducherry 605 008, India 3De...

The asymmetric unit of the title compound,  Contains two independent molecules. The Cu atoms are four coordinated in distorted tetrahedral configuration by two atoms from 5,5`-dimethyl-2,2`- bipyridine and two terminal atoms. In the Cuystal structure, inter molecular hydrogen bonds link the molecules. The are  contacts between the methyl groups and the pyridine and five member rings containing ...

The influence of cation-π interactions on the strength and nature of intramolecular O...H hydrogen bond has been investigated by quantum chemical calculations in orthohydroxy benzaldehyde (HBA) compound. Ab initio calculations have been performed at MP2/6-311++G** level of theory. Vibrational frequencies and physical properties such as chemical potential and chemical hardness of these compounds...

in this study, kinetics and mechanism of the sulfur dioxide adsorption on the single-walled carbon nanotubes (cnt) are investigated. three single-walled carbon nanotubes, including the armchair (6,6), chiral (6,5) and zigzag (6,0) cnts were chosen as the models and the different orientations of so2 molecule relative to the cnt axis were considered. the b3lyp functional within the 6-31g(d) basis...

In this study, paraphenylenediamine was first bonded to the fullerene and was optimized geometrically by Using the quantum chemistry methods. paraphenylenediamine was examined in the isolated state and in the fullerene-bonded state via carbon atoms. In the theoretical research, the simulation was done by the Gauss View software. Then, the bonding orbital calculation was done by using the NBO me...