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Li+ Cation (li+ + cation)
Selected AbstractsLigand-Exchange Processes on Solvated Lithium Cations: Acetonitrile and Hydrogen Cyanide,EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 13 2007Ewa Pasgreta Abstract Solutions of LiClO4 in solvent mixtures of acetonitrile and water, or acetonitrile and nitromethane, were studied by 7Li NMR spectroscopy. Measured chemical shifts indicate that the Li+ cation is coordinated by four acetonitrile molecules. In the binary water/acetonitrile mixture, water coordinates more strongly to Li+ than acetonitrile such that addition of water immediately leads to the formation of [Li(H2O)4]+. The solvent-exchange mechanism for [Li(L)4]+ (L = CH3CN and HCN) was studied by using DFT calculations (RB3LYP/6-311+G**). This process was found to follow a limiting associative mechanism involving the formation of relatively stable five-coordinate intermediates. The suggested mechanisms are discussed with reference to available experimental and theoretical data. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007) [source] Coordination behaviour and two-dimensional-network formation in poly[[,-aqua-diaqua(,5 -propane-1,3-diyldinitrilotetraacetato)dilithium(I)cobalt(II)] dihydrate]: the first example of an MII,1,3-pdta complex with a monovalent metal counter-ionACTA CRYSTALLOGRAPHICA SECTION C, Issue 6 2008Urszula Rychlewska The title compound, {[CoLi2(C11H14N2O8)(H2O)3]·2H2O}n, constitutes the first example of a salt of the [MII(1,3-pdta)]2, complex (1,3-pdta is propane-1,3-diyldinitrilotetraacetate) with a monopositive cation as counter-ion. Insertion of the Li+ cation could only be achieved through application of the ion-exchange column technique which, however, appeared unsuccessful with other alkali metals and the ammonium cation. The structure contains two tetrahedrally coordinated Li+ cations, an octahedral [Co(1,3-pdta)]2, anion and five water molecules, two of which are uncoordinated, and is built of two-dimensional layers extending parallel to the (010) lattice plane, the constituents of which are connected by the coordinate bonds. O,Hwater...O hydrogen bonds operate both within and between these layers. The crystal investigated belongs to the enantiomeric space group P21 with only one (,) of two possible optical isomers of the [Co(1,3-pdta)]2, complex. A possible cause of enantiomer separation during crystallization might be the rigidification and polarization of the [M(1,3-pdta)]2, core, resulting from direct coordination of Li+ cations to three out of four carboxylate groups constituting the 1,3-pdta ligand. The structure of (I) differs considerably from those of the other [MII(1,3-pdta)]2, complexes, in which the charge compensation is realized by means of divalent hexaaqua complex cations. This finding demonstrates a significant structure-determining role of the counter-ions. [source] Tetra-,-chloro-1:2,4Cl;1:3,4Cl -bis(4,4,-dimethyl-2,2,-bipyridine)-2,2N,3,2N -lithium(I)dipalladium(II) tetrakis(pentafluorophenyl)borate dichloromethane 1.196-solvateACTA CRYSTALLOGRAPHICA SECTION C, Issue 10 2003Han Shen In the crystal structure of the title compound, [LiPd2Cl4(C12H12N2)2](C24F20B)·1.196CD2Cl2 or [{(Me2bipy)PdCl2}2(,-Li)]+·B(C6F5)4,·1.196CD2Cl2 (Me2bipy is 4,4,-dimethyl-2,2,-bipyridine), an Li+ cation is stabilized by complexation with two (Me2bipy)PdCl2 units through weak Li,Cl interactions. This compound is thus a rare example of a complex that exhibits an arrested Cl, abstraction. [source] Coordination behaviour and two-dimensional-network formation in poly[[,-aqua-diaqua(,5 -propane-1,3-diyldinitrilotetraacetato)dilithium(I)cobalt(II)] dihydrate]: the first example of an MII,1,3-pdta complex with a monovalent metal counter-ionACTA CRYSTALLOGRAPHICA SECTION C, Issue 6 2008Urszula Rychlewska The title compound, {[CoLi2(C11H14N2O8)(H2O)3]·2H2O}n, constitutes the first example of a salt of the [MII(1,3-pdta)]2, complex (1,3-pdta is propane-1,3-diyldinitrilotetraacetate) with a monopositive cation as counter-ion. Insertion of the Li+ cation could only be achieved through application of the ion-exchange column technique which, however, appeared unsuccessful with other alkali metals and the ammonium cation. The structure contains two tetrahedrally coordinated Li+ cations, an octahedral [Co(1,3-pdta)]2, anion and five water molecules, two of which are uncoordinated, and is built of two-dimensional layers extending parallel to the (010) lattice plane, the constituents of which are connected by the coordinate bonds. O,Hwater...O hydrogen bonds operate both within and between these layers. The crystal investigated belongs to the enantiomeric space group P21 with only one (,) of two possible optical isomers of the [Co(1,3-pdta)]2, complex. A possible cause of enantiomer separation during crystallization might be the rigidification and polarization of the [M(1,3-pdta)]2, core, resulting from direct coordination of Li+ cations to three out of four carboxylate groups constituting the 1,3-pdta ligand. The structure of (I) differs considerably from those of the other [MII(1,3-pdta)]2, complexes, in which the charge compensation is realized by means of divalent hexaaqua complex cations. This finding demonstrates a significant structure-determining role of the counter-ions. [source] | ||||||||||