the effects of substituents on the symmetry and the nature of halogen bonds in [n∙∙∙x∙∙∙n]+-type systems are presented for the yc5h4n∙∙∙x∙∙∙nc5h5 (y = no2, cn, h, ch3, och3, oh, nh2, x = cl, br, i) complexes. some structural parameters, energy data and electronic properties were explored with the density functional theory (dft) calculations. in addition, electrostatic potentials were used in es...

mp2 calculations with cc-pvtz basis set were used to analyze intermolecular interactions in f3cx···yli···nccn and f3cx···nccn···liy triads (x = cl, br; y = cn, nc) which are connected via halogen and lithium bonds. those complexes with the role of liy as halogen acceptor and lithium donor show cooperativity with energy values ranging between -1.97 and -2.92 kj mol-1. those complexes with simult...

Unsurprisingly, education research shows that students engage better when an instructional storyline begins with a surprising claim about topic important in their own lives. Today, everyone understands the importance of immune response to lives, and most find it paradoxical be told some bonds strengthen under applied pulling force. So recent discovery catch-bond behavior T-cell activation is ve...

the molecular geometry of complex of adenine with 8 water molecules was calculated with hartree-fock (hf). the standard 6-31g(d) basis set has been employed. the existence of c-h…o hydrogen bonds between the water molecules and the hydrophobic part of nucleobase is stablished. we optimized structures and computed interaction energies of all complexes of adenine with water molecules step by step...

a quantum chemical investigation was carried out to study the properties of intermolecular f•••f, br•••br and br•••o interactions in crystalline 1-bromo-2,3,5,6-tetrafluoro-nitrobenzene (bfnb). this system was selected to mimic the halogen-halogen as well as halogen bonding interactions found within crystal structures as well as within biological systems. we found that fluorine atoms have weak ...

this study aims to have a sociological explanation of the different forms of participation among khalkhal citizens and the factors affecting it. in this study, the important issue is attention to dimensions of participation. the theoretical framework and model were presented by using the theory of talcott parsons, lipset, habermas, de tocqueville, lerner, and rostow. this research was a survey ...

h6-benzne, h6-garphyne) was studied with MPW1PW91 quantum chemical computations. Quantumtheory of atoms in molecules (QTAIM) was applied to elucidate these complexes Cr-CO bonds. Theellipticity (e) and h values of the Cr-CO bonds were calculated. The amount of pp-dp back-donation ofCr-CO bonds were illustrated by calculation of the magnitude of the quadrupole polarization of c...