A previous theory of separation of motions of core and valence fractions of electrons in a molecule [J. R. Mohallem et al., Chem. Phys. Lett. 501, 575 (2011)] is invoked as basis for the useful concept of Atoms-in-Molecules (AIM) in the stockholder scheme. The output is a new tool for the analysis of the chemical bond that identifies core and valence electron density fractions (core-valence sto...

In the present work, the structural and electronic properties, and conductivity of (5,5) and (6,6) Single Walled Carbon Nanotubes in the ground state have done by using the Hartree-Fock and density functional theory DFT-B3LYP/6-31G* level. Delocalization of charge density between the bonding or lone pair and antibonding orbitals calculated by NBO (natural bond orbital) analysis. These methods a...

It is shown that the response of molecular properties of diatomics such as the total energy, the bond length, and the vibrational Stark shift to an external homogenous electric field (EF) can be predicted from field-free observable properties such as the equilibrium bond length, the bond dissociation energy, the polarizability and dipole moment functions, and the vibrational frequency. Delley [...

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...

ION REACTIONS The technique for estimation of activation energies for simple atom transfer reactions was developed by Johnston and coworkers (1963, 1966). The method is based upon the concept of conservation of bond order during the reaction process. Here bond order is defined as a number which is related to the strength of the chemical bond, hence bond energy-bond order (BEBO). In this notatio...

In the present paper we have theoretically predicted the physical parameters viz. coordination number, constraints, molar volume, fraction of floppy modes, number of lone pair electrons, bond energy, cohesive energy, heat of atomization and mean bond energy for Ge20Te80-xBix (x = 0, 5, 10, 15, 20, 25) glassy alloys. It has been found that average number of constraints, cohesive energy and mean ...

Electronic energy (chemical bond energy) is the exclusive source of utilizable energy in biological systems. The release of this energy is mediated enzymically. The energy required to rupture a single covalent or ionic bond is prohibitively high under physiological conditions [in the range of 80-200 kcal/mol (1 kcal = 4.18 kJ)]. By the technique of the pairing of bond rupture (two juxtaposed bo...

In dynamic force spectroscopy, a (bio-)molecular complex is subjected to a steadily increasing force until the chemical bond breaks. Repeating the same experiment many times results in a broad distribution of rupture forces, whose quantitative interpretation represents a formidable theoretical challenge. In this study we address the situation that more than a single molecular bond is involved i...

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...

The chemical bond and structural features for the most important classes of solid products obtained by reacting chalcogen donors with dihalogens and interhalogens are reviewed. Particular attention is paid to the information the FT-Raman spectroscopy can confidently give about each structural motif considered in the absence of X-ray structural analyses.