Coordination complexes cluster structures

Hg7(SCeHu)i2Br2] Complex cluster structure with central octahedrally coordinated Br 104... 

COORDINATION COMPLEXES AS STRUCTURAL AND FUNCTIONAL MODELS OF THE Mn4 CLUSTER... 

These and many similar examples resulted in a highly successful general picture of transition-metal ions M coordinated by closed-shell ligands L (anionic or neutral) to form complex cluster ions [ML ]9 in solution. The characteristic coordination shell of each M corresponds to a specific number of sites, with idealized geometry that dictates the possible number of distinct [M(Li) (L2)m. .. ]q structural isomers. Each cluster ion is subject to equilibria with other cluster ions or dissociated ligands in solution,... 

Polyrotaxene complexes, 46 271-273 Polysilanes, mass spectra of, 18 251 Polysilazanes, preparation of, 6 265-272 Polysiloxanes, 42 149-150 Polysulfide metal complexes, 31 89-122 cluster structures, 31 96 compound types, 31 91-103 with coordinated polysulfide ligands, 31 91-97... 

In a difference from above, the nickel and copper ICC 874 (X = O) with coordination unit MN202 evidently have tetrahedral structure, which is also characteristic for analogous cobalt and zinc complexes [169], as proved for a zinc complex by x-ray diffraction. In this respect we note a nonstandard behavior of manganese. As a result of the interaction of the ligand 873 (X = 0, R = H, N02 Ar = C6H4R, R =H, OMe, N02) and the acetate of the metal in methanol, together with an expected ICC of type 874 (X = O, M = Mn) [17], tetrameric cluster structures are formed (4.46) [171] ... 

Under anhydrous conditions, tetranuclear vanadium clusters such as [V404 (0CH2)3CCH3 3(0C2H5)3] can be generated in alcoholic solutions with l,l,l-tris(hydroxymethyl)ethane. The coordination does vary somewhat with the alcohol utilized in the preparation, but all retain the tetranuclear structure. Each vanadium nucleus in the complex has octahedral coordination. The clusters are not stable to hydrolysis and decompose in chloroform solution in the presence of just a few equivalents of water [5],... 

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