Ligands coordination number and

NMR-active " Cd ions were employed as a surrogate probe for Zn Indeed, " Cd NMR has been widely employed in the spectroscopic study of metalloproteins which bear Zn(II) in their native state. The adaptable ligand coordination, number and geometry of Cd(II) are rather similar to Zn(II) and in many cases where Cd(II) has replaced Zn(II), the catalytic activity of the metaUoenzymes has been retained even to a low extent . 

More generally, the chemical shifts are due to a combination of valence, electronegativity of the bonding ligands, coordination number, and other structural features. These factors are expressed by Batsanov s (19, 224, 225) concept of coordination charge, t, as... 

To answer this question, it is convenient to construct a table of ligand coordination numbers and electrons for the different components of each complex, as shown here. 

Choppin GR, Wang ZM. Correlation between ligand coordination number and the shift of the Fq - Dq transition frequency in europium(III) complexes. Inorg Chem. 1997 36(2) 249-252. 

Various crown ethers (p. 96) with differing cavity diameters provide a range of coordination numbers and stoichiometries, although crystallographic data are sparse. An interesting series, illustrating the dependence of coordination number on cationic radius and ligand cavity diameter, is provided by the complexes formed by the lanthanide nitrates and the 18-crown-6 ether (i.e. 1,4,7,10,13,16-... 

Development of Coordination Chemistry Since 1930 Coordination Numbers and Geometries Nomenclature of Coordination Compounds Cages and Clusters Isomerism in Coordination Chemistry Ligand Field Theory Reaction Mechanisms... 

Coordination Numbers and Radii. In the transition metal ions, the interaction of the ligand orbitals with the d orbitals of the metal ions generally determines the coordination number and geometry of the oordination sphere about the metal. The... 

The limited number of characterized complexes of arsine and arsenide ligands contain some similar structural motifs to those exhibited for equivalent phosphorus ligands. Coordination numbers of two, three, or four are observed with monomeric up to decameric zinc complexes structurally determined by X-ray crystallography. 

Hydrido-(l-pyrazolyl)borates [H4 B(C3H3N2) ]-, in short [H4 B(pz) ], often with more or less bulky substituents in 3- and/or 5-positions of the pz ring, have been used for the preparation of mononuclear complexes with controlled coordination sphere about a metal.195 With Cd as a metal center different coordination numbers and geometries can be realized, depending on the pyrazolylborate used, but also on the co-ligands. 

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