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Molecular Planarity (molecular + planarity)

Distribution by Scientific Domains
Chemistry100%

Selected Abstracts

Coherent superposition of resonance wave function in terms of weighted orthogonalized natural localized configurations

INTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY, Issue 2 2008
A. H. Pakiari
Abstract In this research, the projection technique has been applied in order to decompose the electronic wave function into its weighted orthogonalized resonance components. These components have been constructed by determinants whose orbitals are selected among natural bond orbitals. However, the procedure is general and any other localized orbitals can be used as well. Both , and , delocalize systems have been considered in order to check the reliability of the calculated resonance weights. For ,-systems, the presented procedure could predict significant decrease of weight of certain resonance structures when the molecular planarity was destroyed. Water cyclic clusters were also tested and the results confirmed the existence of strong ,-delocalization in the clusters. © 2007 Wiley Periodicals, Inc. Int J Quantum Chem, 2008 [source]

The effect of molecular planarity on crystal non-centrosymmetry in benzyl­idene,aniline derivatives

ACTA CRYSTALLOGRAPHICA SECTION C, Issue 6 2002
De-Chun Zhang
In the title compound, N -(2-methoxy­phenyl)-4-nitro­benzyli­deneamine, C14H12N2O3, the two phenyl rings make a dihedral angle of 48.0,(2)° and the nitro group is at an angle of 6.5,(1)° with respect to its attached phenyl ring. In the crystal structure, mol­ecules are related as centrosymmetric pairs through ,,, interactions and are further connected through strong C,H,O hydrogen bonds [C,O 3.4259,(17),Å and C,H,O 167°], forming molecular stacks along [100]. These stacks associate further through longer C,H,O interactions, forming two-dimensional networks. In the c direction, there are only weak van der Waals interactions. The relationship between the molecular planarity and its centrosymmetry is also briefly described. [source]

Red, orange and yellow crystals of 4,5-­bis(4-methoxy­phenyl)-2-(3-nitro­phenyl)-1H -imidazole

ACTA CRYSTALLOGRAPHICA SECTION C, Issue 7 2000
Yoshinobu Inouye
Red non-solvate crystals of the title compound from ethanol, C23H19N3O4, orange solvate crystals from tert -butanol, C23H19N3O4·C4H10O, yellow solvate crystals from dioxane,water, C23H19N3O4·0.5C4H8O2, and intense yellow solvate crystals from benzene,N,N,-dimethylformamide, C23H19N3O4·C6H6, differ from each other in their molecular conformation and hydrogen-bonding scheme. The bathochromic shifts of the crystal color are explained by the molecular planarity and charge-transfer effect among the imidazole mol­ecules. [source]