Neutral ligands, electrically

As can be gathered from Table 6, theory predicts for all resolvable special cases involving liquid membranes that contain the electrically neutral ligand S a selectivity constant ... 

If a liquid membrane contains electrically neutral ligands, for example carrier antibiotics, that are capable of completely enveloping monovalent cations, then ... 

In spite of the simple theoretical treatment of the electrochemical alkali ion selectivity for liquid membranes incorporating electrically neutral ligands, nothing comparable has been achieved for negatively charged ligands. As shown in Table 6 for this type of membrane, two completely different expressions for the selectivity constant can be derived (27, 25, 26), depending on which assumptions are made ... 

In order to investigate the molecular basis of the ion selective behavior of electrically neutral ligands, we made use of model calculations which are summarized in the following. 

Requirements Governing the Suitability of Electrically Neutral Ligands as Carriers for Alkali or Alkaline Earth Metal Ions in Membranes... 

Table 9. Liquid membrane electrodes using electrically neutral ligands as membrane components... 

Since 1966, when Stefanac and Simon (3) developed the first electrodes of this type containing macrotetrolides, valinomycin, and other antibiotics as the active components, the analytical potential of these ion selective sensors has been generally recognized, and forms incorporating various electrically neutral ligands specific for K+ (3,86,87,89,107—110, 118, 119), NHj 85, 112), Ba2+ 113, 114), and other cations 115, 117) have found practical application (Table 9). 

Dependence on So-called Electrically Neutral Ligands. Good donors —e,g, tertiary phosphines, arsines, and stibines—give analogous complexes with almost equal moments when they are associated with halide... 

A choice between two mechanisms which otherwise appear indistinguishable may be made if one of them has a rate constant exceeding that for diffusion control.One mechanism may also be favored if it leads to a consistent trend of results for a family of reactions. The prime evidence for a dissociative mechanism is that a family of reactions has approximately the same rate constants. All of the above factors were used in the assignment of peroxide binding reactions to the electrically neutral ligand. 

You know die charge of die complex and those of the ligands. To find the formulas of the coordination compounds, apply the principle of electrical neutrality. 

The nature of the sites has also a clear influence on complex stability. All ligands listed are electrically neutral. They contain ether, amine or thioether binding sites which contribute to the stability of the AC complexes following the sequence of electrostatic interactions 0> N > S (Table 3). 

Fig. 13. Calculated effect of coordination number on the ion selectivity of electrically neutral model ligands...

E) NHs is a neutral ligand the bromide and the chloride ion both have a -1 charge. Cobalt would have to have a h-3 charge in this compound for the complex compound to be electrically neutral. 

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