Monodentate ligands complexes with, factors affecting stabilities

The fact that the stability constants of monodentate ligand complexes of polyion systems are comparable in magnitude with those of the simple molecule resembled, once corrected for the electrostatic effect, is consistent with expectation based on the statistical arguments discussed earlier. The absence of multidentate complex formation is also predictable. Whereas the formation of MA is not affected by the low accessibility of the polyion species, MA and A, their nonideality, and canceling in the mass action expression for the formation of MA (f +/f - = 1), this is not the case for the bidentate species, because f /(f -) = l/f -, the nonideality term for 1/A" remaining uncanceled. The tendency for bidentate complex formation is, on this basis alone, a factor of f - less likely. 

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