Bond lengths aqua complexes

Alkene complexes Ammine complexes Aqueous chemistry Arsine complexes Binary compounds Bipyridyl complexes Bond lengths acetylacetonate alkene complexes alkyl and aryl complexes ammine complexes aqua ion... 

For the sake of simplicity the aqua ligand is added in cis position to the methyl group, as suggested by the X-ray structure of the di(peroxo) complex [19]. Agreement between calculated and experimental geometries of 5b is very satisfactory bond lengths deviate, in general, at most by 0.04 A. The... 

The study of zinc-aqua complexes as synthetic carbonic anhydrase models has shown a low coordination number and a hydrophobic environment to be prerequisites for a low pK value of the aqua ligand, which is essential for efficient enzyme function. The pK value in the case of 13 is expected to be greater than 10.7, which is the value determined for pentacoordinate [Zn(tren)(H20)](C104)2, in which the water ligand is more strongly bound and thus expected to be more acidic (cf. the discussion of bond lengths, above). Thus, 13 is not expected to show carbonic anhydrase-like reactivity. However, in related tetraazamacrocyclic systems it has been shown that upon... 

Neutron diffraction has been successfully used for structure determinations of aqua complexes of some metal ions, which have isotopes with sufficient differences in scattering lengths to be used for isotopic substitution methods. Not only bond lengths but also coordination numbers and the orientation of the water molecules in the first coordination sphere can then be determined. Several review articles have summarized these results (2-6). 

X-ray diffraction, which can be more generally applied, has also been used for determining structures of aqua complexes of metal ions in aqueous solution. Since hydrogen atoms are weak scatterers of X-rays, their positions and, therefore, the orientation of the water molecules in the hydration sphere, cannot be determined, but bond lengths and to some extent coordination numbers can be obtained. Several review articles have appeared, the most extensive one being that by Magini et al. (7-22). 

As for the lanthanides, actinide complexes display high coordination numbers. A study of the aqua ions of early actinides makes an interesting comparison (Table 11.1 lists numbers of water molecules and bond lengths). 

Table A.2 has been derived from CSD, and, as a result, does not contain every precisely determined metal-ligand interatomic distance. For example, there are many ammine (M-NH3), carbonyl (M-CO), halide (M-Cl etc.) and aqua (M-OH2) complexes which do not fall within the scope of CSD. For such bond types and other metal-non-metal bond length information, the interested reader is referred to the Inorganic Crystal Structure Database [14].

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