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Grid Complex (grid + complex)

Distribution by Scientific Domains
Chemistry100%

Selected Abstracts

Charge-induced modulation of magnetic interactions in a [2 × 2] metal-organic grid complex,

INTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY, Issue 4 2006
C. Romeike
Abstract We investigate the magnetic state of a recently synthesized [2 × 2]-metal-organic grid complex as a function of its redox state. Our analysis of a phenomenological model for the relevant molecular orbitals reveals that additional electrons on the ligands can couple their spins via the bridging metal sites. We find that at certain stages of the reduction of the complex cation, a maximal total spin ground state of the complex (S = 3/2) can be stabilized by the Nagaoka mechanism. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2006 [source]

Cobalt Antiferromagnetic Ring and Grid Single-Molecule Magnet

CHEMISTRY - AN ASIAN JOURNAL, Issue 11 2009
Takuya Shiga Dr.
Grid magnet: A Co8 ring and a Co9 grid complex are synthesized using a multidentate polypyridine-type ligand and are shown to exhibit all antiferromagnetic interactions between metal centers, with the grid complex displaying SMM properties as a result of alternating high spin/low spin metal centers in the outer 8-membered ring. [source]

Self-Assembly, Structure and Solution Dynamics of Tetranuclear Zn2+ Hydrazone [2×2] Grid-Type Complexes

EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 4 2006
Mihail Barboiu
Abstract We describe the self-assembly processes as well as the structural and physico-chemical properties of [2×2]Zn2+4 grid complexes involving the bis-tridentate ligands 7,12, based on bis(hydrazone)pyrimidine complexation subunits and octahedrally coordinated Zn2+ ions. The NMR spectroscopic data and the X-ray crystal structure results indicate that in solution and in the solid state the complexes 13,18 adopt a very compact arrangement providing stable [2×2] hydrazone-grid arrays. The ,,, stacking between the phenyl ring and the hydrazone units of the perpendicular ligands in the complexes induces a perfect orthogonal arrangement suitable for applications in self-organized metallosupramolecular systems. Zinc complexes provide an opportunity to study the acid,base chemistry without the added effects due to paramagnetism or redox chemistry. The intermediate protonated grids undergo relatively rapid proton exchange on the NMR timescale, the presence of a sharp pyrimidine proton resonance suggesting that there is significant delocalization of the negative charge along the backbone of the ligand. Rotation of the phenyl ring is observed. It involves probably a mechanism in which one of the ligands partially dissociates allowing the initially intercalated phenyl group to rotate, before recoordination of the terminal pyridine. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006) [source]