Ternary complexes M

Redox potentials of aquo ions have been the subject of intensive study for many decades. In fact most values were established many years ago, and have been tabulated and discussed frequently.228 Both in relation to redox potentials and to pK values it is important to bear in mind that ternary complexes [M(OH2)yLz]"+ may have properties very different from those of their binary parent ions [M(OH2)I]n+. 

The adjunctive mechanism is veiy dependent on ligand structure since either formation or dissociation of the intermediate ternary complex, M,LM2, can be rate limiting. When the incoming metal, Mj, is a transition metal and the outgoing metal, M2, is an alkaline earth cation, the formation of the intermediate ternary complex is more likely to be limiting (Hering and Morel Mar-gerum et al., 1978). 

From the above interactions schemes, Fig. 3 is proposed as a model for the structure of the activated alcohol-isocyanate-metal ternary complex M and Mx metals are considered separately. 

The results with the [16]aneN5-Mg2+ system indicate the formation of a ternary complex according to Eq. (4). The complex formation constant is 5.6 x 104 M 1 at 25 °C... 

DeLean, A., Stadel, J. M. Lefkowitz, R. J. (1980). A ternary complex model explains the agonist-specific binding properties... 

Weiss, J. M., Morgan, P. H., Lutz, M. W., and Kenakin, T. P. (1996a). The cubic ternary complex receptor-occupancy model. I. Model description. J. Theroet. Biol. 178 151-167. 

FIG. 12 Cyclic voltammogram for Au electrode modified with el6S-tl9-T12Fc ternary complex. Electrolyte solution, aqueous 0.1 M KCl scan rate 25 mV s temperature, 5°C electrode area, 0.02 cm (geometrical). 

CH2—CH(iPr)ion. According to these workers, surprisingly, the content of isomerized units is independent of monomer concentration, conversion and molecular weight. To account for these observations Kenndy et al. (4) proposed a model according to which the initially formed secondary ion-counteranion pair CSG or the more stable tertiary carbenium ion counteranion pair C,G (formed from the former by rate constant kH) can add monomer M to form ternary complexes CSGM or C,GM (with rate constants kc and k c) respectively. Within the former complex the secondary ion can isomerize to the tertiary ion with rate constant k H. Propagation of either ion can occur by incorporation of the complexed monomer into the chain end (with rate constants k or k[, respectively)... 

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