Complexes, quasi labile

Stability constants are not always the best predictive tool for measuring the ease and the extent of chemical reactions involving complexes nor their stability with time, because their kinetic behavior can often be even more crucial. For example, when ligand exchange reactions of ML (e.g., [FeEDTA]) with other metal ions (e.g., Zn2+ or Ca2+) are ki-netically slow, they do not significantly influence ligand speciation. Another typical example of the thermodynamics vs kinetics competition is the fact that the degradability of some metal complexes (e.g., metal-NTA) is related to their kinetic lability, rather than to their thermodynamic stability constants. Kinetic rather than thermodynamic data are then used to classify metal complexes as labile, quasi-labile, slowly labile, and inert (or stable). See Section 3.2.6. 

ML]o and experimentally analyzing the concentration of M as a function of time, one can obtain [ML] at any time by difference. Then, fu can be calculated and plotted (as schematically shown in the Example 2.5). The different types of complexes are then evidenced by their dissociation kinetics. See Figure 3.4. (Note that the quasi-labile curve in this figure does... 

A complex system in a labile equilibrium may adjust itself to an external stimulus by changing its molecular composition. This is known as the dynamic combinatorial library but in fact it corresponds to quasi-dynamics, for we are interested mainly in shifting equilibrium... 

Ordered binary crystals were obtained via cocrystallization of quasi-racemic cyclopalladated complexes in a borderline regime between inertness and lability.Braunstein ef al. devised routes for anchoring a cyclopalladated complex 72 inside a nanoporous alumina membrane. 

Quantitative Modeling of Quasi-Reversible Electrochemical Processes Involving Labile Complexes of Metals... 

Survila, A. (1984) Impedance in the system with forced convection. (6, Quasi-reversible processes in systems of labile complexes). Proa Lithuanian Acad. ScL,... 

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