Following a previous study by de Courcy et al. (Interdiscip. Sci. Comput. Life Sci. 2009, 1, 55-60), we demonstrate in this contribution, using quantum chemistry, that metal cations exhibit a specific topological signature in the electron localization of their density interacting with ligands according to their “soft” or “hard” character. Introducing the concept of metal cation subvalence, we s...

ion molecules with general chemical formula as [li(h2o)] (n=1,2,3), have been chosen as model species toinvestigate the chemical properties of hydrated lithium cations. the rhf(scvs)/ugbs level of calculationhas been used for obtaining equilibrium geometries and rho(r) functions (electron density distributions). by theaid of fundamental physical theorems implemented in quantum theory of atoms i...

two bonding models i.e cumullenic and acetylenic models have been proposed to account for thebonding patterns in linear carbon clusters while the bonding patterns in cyclic and 3d geometries of theseclusters have remained ambiguous.this work presents the bonding patterns in various c4 and c5 pure clusters at mp2/aug-cc-pvtz level oftheory. this subject is studied in the light of modern bonding ...

The intrinsic dynamic and static nature of noncovalent Br-∗-Br interactions in neutral polybromine clusters is elucidated for Br4–Br12, applying QTAIM dual-functional analysis (QTAIM-DFA). asterisk (∗) emphasizes the existence bond critical point (BCP) on interaction question. Data from fully optimized structures correspond to interactions. originates those perturbed generated using coordinates...

С использованием «квантовой теории атомов в молекулах» (QTAIM) определены интегральные электронные характеристики (заряды и объемы) функциональных групп NH, C(O)H, SH, CH, OH, CHOH, CHCOOH, COOH, CHC(O)NH, CHS, СН, CH(CH)-OH C(O)NH десяти молекул α-аминокислот такого же количества α-аминоальдегидов. Показано, что преобразование структуры (замена СООН на C(O)H) снижает заряд заместителя аминогру...

Colchicine is a tropolone alkaloid from Colchicinum autumnale. It shows antifibrotic, antimitotic, and anti-inflammatory activities, and is used to treat gout and Mediterranean fever. In this work, complexes of colchicine with zinc(II) nitrate were synthesized and investigated using DFT, 1H and 13C NMR, FT IR, and ESI MS. The counterpoise-corrected and uncorrected interaction energies of these ...

in the present work, an extensive theoretical calculation study on histidine-histidine dipeptide in gas phase is done by using dft method with gaussian 98 program. through investigations on the molecular geometries of this molecule it is found that there is six rings in the molecules not two rings. the presence of four intramolecular hydrogen bonds is responsible for the formation of additional...

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 ...