Ligand number

A reference isomer is defined as the structure where ligand number I is on skeleton position 1, ligand no. 2 is on skeleton position 2, etc. This reference isomer obtains the descriptor + 1). 

The OH/Al mole ratio or ligand number ris an important factor in the speciation of Al cations in the PAG product. Product composition also... 

Table 2. Ligand Number at which Charge Reduction from M2+ to M+ Occurs...

The determination of the ligand number (27) for adsorption reactions has been discussed by Hohl and Stumm (22). The following example illustrates the relationship between the net proton release and ligand number. 

ESEM results on the interaction of silica-exchanged Cu(II) with a range of adsorbates showed that one or two adsorbate molecules were able to coordinate to the Cu depending on the chemical interaction, polarity and size (7[2). Differences in A, were observed for N- and O-coordinated ligands, but these seem to reflect a change in coordination symmetry and not a difference in adsorbate ligand number. N-coordinated ligands form approximately square planar... 

There are linear correlations between log k (formation) and certain properties of the ligand (number of nitrogen atoms or electron-donor constant ). The enhanced rate resides largely... 

An initial step in data analysis is to develop an equation that represents the experimental data reasonably. Although previous sections dealt with this issue, the approach assumed that certain species are formed. Two alternatives to this procedure are discussed here, both yielding the approximate stoichiometry of the complexes formed in the system. The most elementary is referred to as Job s method, while the ligand number method, developed by J. Bjerrum, is slightly more advanced. 

In 1941, J. Bjerrum [65] developed the useful concept of average ligand number, n, defined as the mean number of ligands per central atom ... 

The average ligand number can be used to obtain approximate equilibrium constants, as described by [65], assuming that at half integer -values the two adjacent complexes dominate e.g., at = 0.5 the species and MA dominate, while at il = 1.5 MA and MA dominate, etc.. The following expression for the stepwise formation constant is approximately valid at... 

If the first bonded atom is the same in at least two ligands, the priority is determined by comparing the next atoms in each of these ligands. Thus, ethyl (HjCCHj—), with one C and two H s on the first bonded C, has priority over methyl(—CHj), with three H s on the C. For butyl groups, the order of decreasing priority (or increasing ligand number) is... 

Regioselective synthesis is examined mainly on the basis of the conception of competitive coordination and the principle of hard and soft acids and bases [14]. A description of polyhedron-programmed synthesis is given, taking into consideration thin structure compounds to be used as ligands (number, nature, and mutual situation of donor centers and the presence and character of organic fragments, annealed to a metal-cycle). 

The ligand number, h can be determined by four methods. The values of h can be calculated from equation (3.4) provided M and A are known and that a can be measured. When very strong complexes are involved, A>a in the concentration range where A < AM and the value of h can be obtained from the relationship... 

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