Assigning bond orders is a necessary and essential step for characterizing a chemical structure correctly in force field based simulations. Several methods have been developed to do this. They all have advantages but with limitations too. Here, an automatic algorithm for assigning chemical connectivity and bond order regardless of hydrogen for organic molecules is provided, and only three dimen...

he aromatic behavior of the azo-linked cyclopentadienide derivatives have been revealed in various natural compounds. In Tthis research, density functional theory (DFT) calculations at the B3LYP level are used to optimize the geometry of the compounds. In addition, we were interested in the evaluation of the aromaticity of the selected compounds using nucleus independent chemical shifts NIC...

Ab initio HF/6-31G* Methode was employed to calculate the bond length in 2- phosphinanes when electronegative groups was at C-2 tend axial and equatorial positions. The magnitude of the anomeric effect depends on the nature of the substituent, the effect of the substituent can be seen by comparing the bond length in 2-chloro and 2- boromo substituented phosphinanes. The effect of anomeric effec...

Ab initio HF/6-31G* Methode was employed to calculate  the bond length in 2- phosphinanes  when electronegative groups was at C-2 tend axial and equatorial positions. The magnitude of  the anomeric effect depends on the nature of the substituent, the effect of the substituent can be seen by comparing the bond length in 2-chloro and 2-boromo substituented phosphinanes. The effect of anomeric eff...

The crystal structure of the ®rst reported non-substituted N-methyldioxazaborocane con®rms that the presence of a methyl group attached to the N atom introduces an N!B bond length that is longer than that in a simple dioxazaborocane ring. The presence of more N atoms in the vicinity of the B atom in the title compound [systematic name: 6a-(6bromopyridin-2-yl)-3a-methyl-2,3,4,5-tetrahydro-1,6-di...

the aim of this research is studying the effects of ge-doped on co adsorption on the outer and inner surfaces of (6, 0) zigzag model of boron nitride nanotube (bnnts) by using dft theory. for this purpose, eight models of co adsorption on the surfaces of bnnts are considered. at first step, all structures were optimized at b3lyp and 6-31g (d) standard base set and then the electronic structure,...

The complete molecule of title compound, C(58)H(58)P(4), is generated by a crystallographic twofold rotation axis that passes through the center of the C(methine)-C(methine) bond of length 1.582 (4) Å. The C-P bond lengths are 1.8824 (19) and 1.8991 (19) Å. The P-C-P angle of 109.69 (9)° is essentially equal to the expected value of 109.5° for a tetra-hedral C atom. Although the C(methine)-P-C(...

carbon nanotubes (cnts) are specific structures with valuable characteristics. in general, the structure of each nanotube is defined by a unique chiral vector. in this paper, different structures of short single-walled cnts are simulated and their mechanical properties are determined using finite element method. for this aim, a simple algorithm is presented which is able to model the geometry o...

Ab initio HF/6-31G* Methode was employed to calculate  the bond length in 2- phosphinanes  when electronegative groups was at C-2 tend axial and equatorial positions. The magnitude of  the anomeric effect depends on the nature of the substituent, the effect of the substituent can be seen by comparing the bond length in 2-chloro and 2-boromo substituented phosphinanes. The effect of anomeric eff...

In the present work, the sensitivity to the moisture (hygroscopisity) is studied for 3,4-dinitropyrazole (DNP) as a famous energetic molecule. All of the DNP-H2O complex systems (1-3) as well as individual molecules were optimized and bond lengths, bond angles, dihedral angles, charge transfer and stability via NBO analysis, corrected interaction energies with ZPE + BSSE and hydrogen bonds anal...