Kinetic compensation effect solid state

An anion effect is also reported for the solid-state anations of cis-[Co(en)2(py)X]Y2 (X- = Cl-or Br- Y- = Br" or I"). Experimental conditions affect activation parameters, and the kinetic compensation effect is observed (that is, a is linearly correlated with log A). However, the correlation is different for [Co(en)2(py)X]Br2 than for [Co(en)2(py)X]I2.71 This result suggests that the chemical process of importance is anion-dependent. It is proposed that the Co—py bond strength is affected by polarization effects due to the surrounding ionic halides. 

Kappa notation, 115 3-Ketoiminates metal complexes gas chromatography, 560 Ketoxime, 2-pyridylmethyl-in gravimetry, 533 Ketoxime, 2-pyridylphenyl-in gravimetry, 533 Kinetic compensation effect ligand exchange solid state, 469... 

Kinetic parameters. The hterature contains numerous reports of the rate equations identified for particular crystolysis reactions, together with the calculated Arrhenius parameters. However, reproducible values of (Section 4.1.) have been reported by independent researchers for relatively few solid state decompositions. Reversible reactions often yield Arrhenius parameters that are sensitive to reaction conditions and can show compensation effects (Section 4.9.4.). Often the influences of procedural variables have not been carefully identified. Thus, before the magnitudes of apparent activation energies can be compared, attempts have to be made to relate these values to particular reaction steps. 

The phenomenon of compensation is not unique to heterogeneous catalysis it is also seen in homogeneous catalysts, in organic reactions where the solvent is varied and in numerous physical processes such as solid-state diffusion, semiconduction (where it is known as the Meyer-Neldel Rule), and thermionic emission (governed by Richardson s equation ). Indeed it appears that kinetic parameters of any activated process, physical or chemical, are quite liable to exhibit compensation it even applies to the mortality rates of bacteria, as these also obey the Arrhenius equation. It connects with parallel effects in thermodynamics, where entropy and enthalpy terms describing the temperature dependence of equilibrium constants also show compensation. This brings us the area of linear free-energy relationships (LFER), discussion of which is fully covered in the literature, but which need not detain us now. 

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