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Ligand Arrangement (ligand + arrangement)

Distribution by Scientific Domains
Chemistry100%

Selected Abstracts

Surprising Coordination Geometry Differences in CeIV - and PuIV -Maltol Complexes,

EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 13 2008
Géza Szigethy
Abstract As part of a study to characterize the detailed coordination behavior of PuIV, single-crystal X-ray diffraction structures have been determined for PuIV and CeIV complexes with the naturally occurring ligand maltol (3-hydroxy-2-methylpyran-4-one) and its derivative bromomaltol (5-bromo-3-hydroxy-2-methylpyran-4-one). Although CeIV is generally accepted as a structural analog for PuIV, and the maltol complexes of these two metals are isostructural, the corresponding bromomaltol complexes are strikingly different with respect to ligand orientation about the metal ion: All complexes exhibit trigonal dodecahedral coordination geometry but the CeIV,bromomaltol complex displays an uncommon ligand arrangement not found in the PuIV complex.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) [source]

AgI and CuI binuclear macrocyclic complexes with 1-(3-pyridyl)­ethano­ne oxime

ACTA CRYSTALLOGRAPHICA SECTION C, Issue 1 2004
Ingrid Socorro
Bis­[,-1-(3-pyridyl)­ethanone oxime-,2N:N,]­bis­[nitrato­sil­ver(I)], [Ag2(NO3)2(C7H8N2O)2], crystallizes as a centrosymmetric binuclear macrocylic complex containing silver(I) ions bridged by the organic 1-(3-pyridyl)­ethanone oxime ligand. The ligand coordinates via the pyridine and the oxime N atoms. A similar metal,ligand arrangement was found in the copper(I) complex catena -poly­[[bis­[,-1-(3-pyridyl)­ethano­ne oxime-,2N:N,]­dicopper(I)]-di-,-iodo], [Cu2I2(C7H8N2O)2]n, but here the centrosymmetric macrocycles are connected by double anion bridges, resulting in the formation of a one-dimensional coordination polymer. [source]

(S)-Tricarbonyl[(1,2,3,4-,)-(5R,6S)-1-chloro-5,6-dimethoxycyclohexa-1,3-diene]iron(0)

ACTA CRYSTALLOGRAPHICA SECTION C, Issue 7 2000
Silvia Russi
The title compound, [Fe(C8H11ClO2)(CO)3], has been synthesized, isolated and characterized by single-crystal X-ray diffraction. The mol­ecule crystallizes in the orthorhombic space group P212121. The metal,ligand arrangement is typical of (1,3-diene)­tri­carbonyl­iron complexes. [source]

"Breathing" in Adsorbate-Responsive Metal Tetraphosphonate Hybrid Materials

CHEMISTRY - A EUROPEAN JOURNAL, Issue 27 2009
Rosario M.
Abstract Breathe easy: Reversible H2O and NH3 gas uptake by 2D calcium tetraphosphonates (see figure) is accompanied by framework structural changes similar to those previously reported for some carboxylate-based hybrids. This breathing mechanism is accompanied by a volume increase of 55,%, while maintaining the topology and crystallinity of the material. The structures of various layered calcium tetraphosphonates (CaH6DTMP; H8DTMP=hexamethylenediamine tetrakis(methylenephosphonic acid)), have been determined. Starting from CaH6DTMP,2H2O, thermal treatment and subsequent exposure to NH3 and/or H2O vapors led to four new compounds that showed high storage capacity of guest species between the layers (up to ten H2O/NH3 molecules) and a maximum volume increase of 55,%. The basic building block for these phosphonates consists of an eight-membered ring chelating Ca2+ through two phoshonate groups, and the organic ligand is located within the layers, which are held together by hydrogen bonds. The structural analysis revealed that the uptake/removal of guest species (H2O and NH3) induces significant changes in the framework not only by changing the interlayer distances but also through important conformational changes of the organic ligand. An anisotropic breathing motion could be quantified by the changes of the unit-cell dimensions and ligand arrangements in four crystalline derivatives. Complete characterization revealed the existence of interconversion reactions between the different phases upon gas uptake and release. The observed behavior represents, to the best of our knowledge, the first example of a breathing-like mechanism in metal phosphonates that possess a 2D topology. [source]