نتایج جستجو برای: quantum theory of atoms in molecules qtaim

تعداد نتایج: 24511444  

2009
Zvonimir Maksić Sławomir Janusz Grabowski

Interactions classified as intermolecular resonance assisted hydrogen bonds (RAHBs) are analyzed here. Hence the MP2/6-311++G(d,p) calculations for dimers of formic, acetic and pyrrole-2carboxylic acid (PCA) were performed. The similar calculations were carried out for formamide and its fluorine derivatives’ dimers as well as the tautomeric forms of the latter species. The Quantum theory of Ato...

Oyebamiji Abel Kolawole Semire Banjo

In this paper, quantum chemical parameters at density functional theory (DFT) B3LYP/6-31G** (d,p) level of theory were calculated for three organic corrosion inhibitors [N-benzoyl-N-(p-aminophenyl) thiourea, N-benzoyl-N-(thiazole) thiourea and N-acetyl-N-(dibenzyl) thiourea. The calculated molecular descriptors such as the HOMO, LUMO, dipole moment, chemical potential (μ), chemical hardness (ղ)...

Journal: :Baghdad Science Journal 2023

Numerous integral and local electron density’s topological parameters of significant metal-metal metal-ligand bonding interactions in a trinuclear tetrahydrido cluster [(Cp* Ir) (Cp Ru)2 (μ3-H) (μ-H)3]1 = η5 -C5Me5), (Cp* -C5Me4Et) were calculated interpreted by using the quantum theory atoms molecules (QTAIM). The properties bond critical points such as delocalization indices δ (A, B), density...

Mehdi Esrafili, Mohammad Solimannejad

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 ...

2015
Sławomir J. Grabowski Helmut Cölfen

A search through the Cambridge Structural Database (CSD) for crystal structures containing the [FHF] ́ anion was carried out. Forty five hydrogen bifluoride structures were found mainly with the H-atom moved from the mid-point of the F . . . F distance. However several [FHF] ́ systems characterized by D8h symmetry were found, the same as this anion possesses in the gas phase. The analysis of CSD ...

2012
Anna Krawczuk-Pantula Daniel Pérez Katarzyna Stadnicka Piero Macchi

In this paper, the distributed atomic polarizabilities computed within the Quantum Theory of Atoms in Molecules are discussed. Methods are presented to calculate and visualize symmetric atomic polarizability tensors, with proved additivity to molecular polarizabilities. The analysis of QTAIM bond polarizabilities is also presented for some simple molecules and potential applications in material...

پایان نامه :دانشگاه آزاد اسلامی - دانشگاه آزاد اسلامی واحد تهران مرکزی - دانشکده علوم پایه 1390

abstract the cr(iii) and zn(ii) complexes with 2-((9,10-dihydro-1-hydroxy-9,10-dioxaanthracen-4-yloxy)carbonyl)benzoic acid as ligand have been prepared by reacting cr(no3) and zn(no3)2 and ligand in cloroform. the cr and zn complexes with 2-((9,10-dihydro-1-hydroxy-9,10-dioxaanthracen-4-yloxy)carbonyl) were also prepared in chloroform and aceton solutions. the uv-visible and ft-ir spectra of...

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...

Journal: :Physical chemistry chemical physics : PCCP 2013
Sławomir J Grabowski

Hydrogen and halogen bonds are compared on the basis of ab initio calculations performed for complexes linked through these interactions. The Quantum Theory of Atoms in Molecules (QTAIM) and the Natural Bond Orbitals (NBO) method are applied for a deeper understanding of the nature of interactions. Both interactions are ruled by the same effects of hyperconjugation and rehybridization. In gener...

Journal: :journal of physical & theoretical chemistry 2009
a. kazemi babaheydari k. zare f. mollaamin

this study concerns about quantum chemical modeling behavior of 02 on cr (100)surface by using density functional theory (dft) by lanl2dz and 6 — 31g* basissets, we presented the results of our first principles electronic structure calculationson the 02 molecules and their interface with cr (100) surface. the chromium metalhas the body-centered cubic structure, and chromium cluster has five cr ...

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