Eleven-coordinate compounds

Earlandite structure, 6,849 Edge-coalesced icosahedra eleven-coordinate compounds, 1, 99 repulsion energy coefficients, 1,33,34 Edta — see Acetic acid, ethylenediaminetetra-Effective atomic number concept, 1,16 Effective bond length ratios non-bonding electron pairs, 1,37 Effective d-orbital set, 1,222 Egta — see Acetic acid,... 

There are no known compounds [M(unidentate)u] and it does not appear likely that any could be prepared. However, the geometry of these hypothetical compounds is a useful starting point to the stereochemistries of eleven-coordinate complexes containing chelate groups, such as [Th(N03)4(H20)3]-2H20417 418 and [La(N03)3(H20)5]H20.419... 

The structure of this compound, inferred from nB NMR spectroscopy (26) is shown in Fig. 19. The metal resides at the high-coordinate vertex, while the 2 polyhedral carbon atoms occupy the two low-coordinate positions in the closed eleven-vertex geometry. The analogous Fe(III) compound was formed using Fe(II) in the polyhedral expansion reaction (24). 

The two parts of the present volume contain seventeen chapters written by experts from eleven countries. They cover computational chemistry, structural chemistry by spectroscopic methods, luminescence, thermochemistry, synthesis, various aspect of chemical behavior such as application as synthons, acid-base properties, coordination chemistry, redox behavior, electrochemistry, analytical chemistry and biological aspects of the metal enolates. Chapters are devoted to special families of compounds, such as the metal ynolates and 1,2-thiolenes and, besides their use as synthons in organic and inorganic chemistry, chapters appear on applications of metal enolates in structural analysis as NMR shift reagents, catalysis, polymerization, electronic devices and deposition of metals and their oxides. 

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