Ligands ordering

Complexes included Section of chapter Ligand order ... 

Comparison of cobalt(III) and platinum(II) complexes, therefore, provides further evidence for the duality of mechanism (a and v) for the trans effect in the latter and shows that there is no single order of ligands which can be transferred from one metal cation to another. A comparison of the ligand orders observed for different metal cations should lead to a much better understanding of the importance of different types of bonds between the metal and ligand, and hence of the chemical properties of complexes. It is hoped that this review will stimulate interest in obtaining more experimental data on cis and trans effects in complexes of other metal cations. 

Table I (2,5,6,7). Figure 2 further illustrates changes in electronic spectra for chloroform solutions. In benzene, electronic spectra, though slightly different, are generally similar (Figure 3). Such differences caused by solvent effects may not be unlike subtle differences found between certain hemeproteins. The shifts in electronic spectra attributed to changes in axial ligand follow the same ligand order as that for the other physical...

Effects of non-leaving ligands, and of chelating ligands in particular, on reactivities have been reviewed. The cis and trans influences, i.e. initial-state effects as far as kinetic phenomena are concerned, of some groups in platinum(ii) complexes have been assessed by CNDO-MO calculations. The cis influences were found to be comparable in magnitude to trans influences, but the ligand orders in the two series of influences were not identieal. ... 

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