in present study, the density functional theory (dft-b3lyp) method with svp basis set was used for optimizing and studying the electronic structural properties of cis and trans isomers of bis-(5-nitro-2h-tetrazolato-n2) tetraammine cobalt (iii) perchlorate (bncp) as powerful explosives at 298.15 k temperature and 1 atmosphere pressure. and also, natural bond orbital (nbo) population analysis an...

Resonance weights derived from the Natural Resonance Theory Ž . NRT , introduced in the preceding paper are used to calculate ‘‘natural bond order,’’ ‘‘natural atomic valency,’’ and other atomic and bond indices reflecting the resonance composition of the wave function. These indices are found to give Ž significantly better agreement with observed properties empirical valency, . bond lengths th...

Quantum chemical calculations have been performed to compute optimized molecular geometry, atomic charges and vibrational characteristics for 2-hydroxy-3-methoxy-N-(2-chloro-benzyl)-benzaldehyde-imine (C15H14O2NCl) in the ground state using restricted Hartree-Fock (RHF) and density functional theory (DFT) methods with 6-31+G** basis set. NBO analysis is also performed. The IR and Raman spectra ...

Having conducted fundamental projects, scientists have expressed their hope to develop the use of carbon nanotubes to release drugs. It is important to release drugs in cell without damaging healthy cells of tissues under study. Researchers have shown the fact that nanotubes can perform this function perfectly. To this objective, in the present study the interactions between four anti-cancer dr...

Molecular structure, isomerism, conformational stability and intramolecular hydrogen bonding (IHB) of cis-enol forms of 1-(n-pyridyl)butane-1,3-diones (nPBD) (n = 2, 3, or 4) have been investigated by means of density functional theory (DFT) calculations. Energy differences for all possible nPBD cis-enol forms of isomers with respect to the most stable form of the correspondin...

the character of the intermolecular interactions in cl2-hx (x =f, cl and br) complexes has been investigated by means of the second-order möller–plesset perturbation theory (mp2) and the density functional theory (dft) calculations. the results show that there are two types of lowest interaction potential equilibrium structures in the interactions between cl2 and hx: x∙∙∙cl type geometry and hy...

In this study interaction of phenothiazine sulfur dye with (5, 5) armchair open-end boron nitride nanotubes (BNNTs) in interaction (with a length of 7 Å) was investigated. The impacts of the estereoelectronic effect associated with donor-acceptor electron delocalizations, dipole-dipole interactions and total steric exchange energies on the structural and electronic properties and reactivity of ...

Having conducted fundamental projects, scientists have expressed their hope to develop the use of carbon nanotubes to release drugs. It is important to release drugs in cell without damaging healthy cells of tissues under study. Researchers have shown the fact that nanotubes can perform this function perfectly. To this objective, in the present study the interactions between four anti-cancer dr...

Beta-turns play an important role in peptide and protein chemistry, biophysics, and bioinformatics. The aim of this research was to study short linear peptides that have a high propensity to form beta-turn structures in solution. In particular, we examined conformational ensembles of beta-turn forming peptides with a general sequence CBz-L-Ala-L-Xaa-Gly-L-Ala-OtBu. These tetrapeptides, APGA, A(...

in this article, theoretical studies on the selective complexation of the halide ions (f¯, cl¯ and br¯) and ion pairs (na+f¯, na+cl¯ and na+br¯) with the cyclic nano-hexapeptide (cp) composed of l-proline have been performed in the gas phase. in order to calculate the dispersion interaction energies of the cp and ions, dft-d3 calculations at the m05-2x-d3/6-31g(d) level was employed. based on t...