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Chain Compounds (chain + compound)

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Chemistry100%

Selected Abstracts

Compressed Octahedral Coordination in Chain Compounds Containing Divalent Copper: Structure and Magnetic Properties of CuFAsF6 and CsCuAlF6

CHEMISTRY - A EUROPEAN JOURNAL, Issue 20 2004
Zoran Mazej Dr.
Abstract Crystal structures and magnetic investigations of CuFAsF6 and CsCuAlF6 are reported. Together with KCuAlF6, these appear to be the only examples of Jahn,Teller pure CuII compounds containing only one type of ligand that exhibits a compressed octahedral coordination geometry. The Rietveld method has been used for refining the CsCuAlF6 structure based on neutron powder diffraction data at 4 K. The compound crystallizes in space group Pnma (no. 62) with a=7.055(1), b=7.112(1), c=10.153(1) Å and Z=4 at 4 K. The structure is built from infinite [CuF5]n3n, chains of [CuF6]4, octahedra running along the [1,0,0] direction and (AlF6)3, octahedra connected by corners in the trans position, thus giving rise to chains oriented along the [0,1,0] direction. Single crystals of CuFAsF6 were prepared under solvothermal conditions in AsF5 above its critical temperature. The structure was determined from single-crystal data. CuFAsF6 crystallises in the orthorhombic space group Imma (No. 74) with a=10.732(5), b=6.941(3), c=6.814(3) Å and Z=4 at 200 K. The structure can also be described in terms of one-dimensional infinite [CuF5]n3n, chains of tilted [CuF6]4, octahedra linked by trans -vertices running along the b axis. The [CuF5]n3n, chains are connected through [AsF6], units sharing joint vertices. The compressed octahedral coordination of CuII atoms in CuFAsF6 and CsCuAlF6 compounds at room temperature is confirmed by Cu K-edge EXAFS (extended x-ray absorption fine structure) analysis. For both compounds strong antiferromagnetic interactions within the [CuF5]n3n, chains were observed (,p=,290±10 K and ,p=,390±10 K for CuFAsF6 and CsCuAlF6, respectively). The peculiar magnetic behaviour of chain compounds containing divalent copper at low temperature could be related to uncompensated magnetic moments in the one-dimensional network. [source]

Metal Aminocarboxylate Coordination Polymers with Chain and Layered Structures

CHEMISTRY - A EUROPEAN JOURNAL, Issue 23 2005
Meenakshi Dan
Abstract The synthesis and structures of metal aminocarboxylates prepared in acidic, neutral, or alkaline media have been explored with the purpose of isolating coordination polymers with linear chain and two-dimensional layered structures. Metal glycinates of the formulae [CoCl2(H2O)2(CO2CH2NH3)] (I), [MnCl2(CO2CH2NH3)2] (II), and [Cd3Cl6(CO2CH2NH3)4] (III) with one-dimensional chain structures have been obtained by the reaction of the metal salts with glycine in an acidic medium under hydro/solvothermal conditions. These chain compounds contain glycine in the zwitterionic form. 4-Aminobutyric acid transforms to a cyclic amide under such reaction conditions, and the amide forms a chain compound of the formula [CdBr2(C4H7NO)2] (IV). Glycine in the zwitterionic form also forms a two-dimensional layered compound of the formula [Mn(H2O)2(CO2CH2NH3)2]Br2 (V). 6-Aminocaproic acid under alkaline conditions forms layered compounds with metals at room temperature, the metal being coordinated both by the amino nitrogen and the carboxyl oxygen atoms. Of the two layered compounds [Cd{CO2(CH2)5NH2}2],2,H2O (VI) and [Cu{CO2(CH2)5NH2}2],2,H2O (VII), the latter has voids in which water molecules reside. [source]

One-dimensional Infinite Chain Organotin Compounds: Synthesis and Structural Characterization of Triphenyltin Thiazole-2-carboxylate and Triphenyltin 3-Pyridinylcarboxylate

CHINESE JOURNAL OF CHEMISTRY, Issue 10 2002
Han-Dong Yin
Abstract Triphenyltin thiazole-2-carboxylate (1) and triphenyltin 3-pyridinylcarboxylate (2) were synthesized by the reaction of sodium thiazole-2-carboxylate or sodium 3-pyridinylcarboxylate with the triphenyltin chloride and their crystal structures were determined by single crystal X-ray diffraction analysis. In the structure of 1, the tin atom is five-coordinated in a distorted trigonal bipyramidal structure. Due to the presence of a close intermolecular Sn,S interaction distance of 0.3666 nm, the structure can be described as a weakly-bridged one-dimensional chain compound. In the structure of 2, the tin atom is five-coordinated with bridging 3-pyridinylcarboxylate ligands N atom and resulting structure is one-dimensional chain compound. [source]

N - n -Alkyl N,N -dimethylammonioacetic acid bromides: the first complete series of crystal and molecular structure determinations of an ­amphiphilic compound with alkyl chain lengths n = 1,..., 16

ACTA CRYSTALLOGRAPHICA SECTION B, Issue 1 2000
Rainer Rudert
The molecular and crystal structures of 16 N - n -alkyl N,N -dimethylammonioacetic acid bromides with chain lengths between n = 1 and n = 16 have been determined. All compounds from n = 5 to n = 16 form bilayers with interdigitated chains. The even-numbered chains display the chain packing type M2II. The chain packing of the odd-numbered chain compounds is less regular. The head groups of all compounds are connected via electrostatic N+,Br, interactions, and by OH,Br, hydrogen bonds. The compounds with short chains are packed in different ways. Their molecular conformation depends on the crystal packing. [source]

Metal Aminocarboxylate Coordination Polymers with Chain and Layered Structures

CHEMISTRY - A EUROPEAN JOURNAL, Issue 23 2005
Meenakshi Dan
Abstract The synthesis and structures of metal aminocarboxylates prepared in acidic, neutral, or alkaline media have been explored with the purpose of isolating coordination polymers with linear chain and two-dimensional layered structures. Metal glycinates of the formulae [CoCl2(H2O)2(CO2CH2NH3)] (I), [MnCl2(CO2CH2NH3)2] (II), and [Cd3Cl6(CO2CH2NH3)4] (III) with one-dimensional chain structures have been obtained by the reaction of the metal salts with glycine in an acidic medium under hydro/solvothermal conditions. These chain compounds contain glycine in the zwitterionic form. 4-Aminobutyric acid transforms to a cyclic amide under such reaction conditions, and the amide forms a chain compound of the formula [CdBr2(C4H7NO)2] (IV). Glycine in the zwitterionic form also forms a two-dimensional layered compound of the formula [Mn(H2O)2(CO2CH2NH3)2]Br2 (V). 6-Aminocaproic acid under alkaline conditions forms layered compounds with metals at room temperature, the metal being coordinated both by the amino nitrogen and the carboxyl oxygen atoms. Of the two layered compounds [Cd{CO2(CH2)5NH2}2],2,H2O (VI) and [Cu{CO2(CH2)5NH2}2],2,H2O (VII), the latter has voids in which water molecules reside. [source]

Compressed Octahedral Coordination in Chain Compounds Containing Divalent Copper: Structure and Magnetic Properties of CuFAsF6 and CsCuAlF6

CHEMISTRY - A EUROPEAN JOURNAL, Issue 20 2004
Zoran Mazej Dr.
Abstract Crystal structures and magnetic investigations of CuFAsF6 and CsCuAlF6 are reported. Together with KCuAlF6, these appear to be the only examples of Jahn,Teller pure CuII compounds containing only one type of ligand that exhibits a compressed octahedral coordination geometry. The Rietveld method has been used for refining the CsCuAlF6 structure based on neutron powder diffraction data at 4 K. The compound crystallizes in space group Pnma (no. 62) with a=7.055(1), b=7.112(1), c=10.153(1) Å and Z=4 at 4 K. The structure is built from infinite [CuF5]n3n, chains of [CuF6]4, octahedra running along the [1,0,0] direction and (AlF6)3, octahedra connected by corners in the trans position, thus giving rise to chains oriented along the [0,1,0] direction. Single crystals of CuFAsF6 were prepared under solvothermal conditions in AsF5 above its critical temperature. The structure was determined from single-crystal data. CuFAsF6 crystallises in the orthorhombic space group Imma (No. 74) with a=10.732(5), b=6.941(3), c=6.814(3) Å and Z=4 at 200 K. The structure can also be described in terms of one-dimensional infinite [CuF5]n3n, chains of tilted [CuF6]4, octahedra linked by trans -vertices running along the b axis. The [CuF5]n3n, chains are connected through [AsF6], units sharing joint vertices. The compressed octahedral coordination of CuII atoms in CuFAsF6 and CsCuAlF6 compounds at room temperature is confirmed by Cu K-edge EXAFS (extended x-ray absorption fine structure) analysis. For both compounds strong antiferromagnetic interactions within the [CuF5]n3n, chains were observed (,p=,290±10 K and ,p=,390±10 K for CuFAsF6 and CsCuAlF6, respectively). The peculiar magnetic behaviour of chain compounds containing divalent copper at low temperature could be related to uncompensated magnetic moments in the one-dimensional network. [source]