When we review the literature we find many different values used, and none disclose where and how they got the A and E values they employ, or why the value they use is different from others. References appreciated.
Apart from differences in experimental conditions, the kinetic compensation effect (KCE) can be the reason.
The Arrhenius parameters are usually determined from data corresponding to rather narrow temperature intervals and they are strongly log-linearly correlated (log A = a.E + b). It means that the Arrhenius eqation is an ill-conditioned regression model -- even small errors in data will induce large differences in the kinetic parameters. On the other hand, the rate constants (half lifes, etc.) calculated from such different {A,E} sets are usually close to each other.
Good papers on this phenomenon are
Barrie, P. J. Phys. Chem. Chem. Phys., 2012,14, 318-326. https://dx.doi.org/10.1039/C1CP22666E
Barrie, P. J. Phys. Chem. Chem. Phys., 2012,14, 327-336. https://dx.doi.org/10.1039/C1CP22667C
What does "Arrhenius integral" mean?
See "Arrhenius plot in":
http://en.wikipedia.org/wiki/Arrhenius_plot
We derived E=340kJ/mol, and A=1.6x10^55 s^−1.
See details in our paper about modeling of photocoagulation:
http://web.stanford.edu/~palanker/publications/dynamics_retinal_photocoagulation.pdf
Daniel, Thank you! Taking a skiing break, I see. I will pass your answer on to my friends who can understand it. Best, Jeff
I think these values are different for each system. E depending on bond breakage and formation in a reaction system. So to have a best value I don't think its very right. A for solution systems is however between 109 to 1012.
In fact there are many temperature dependent equations for rate constant. Why Arrhenius equation is most popular is because it gives better insights into what happens during a chemical reaction. You may have check this up in some chemical kinetics texts like Atkins 2nd Edition and others. Thanks.
Jeffrey,
your question is to certain extent confusive. "The A and E values" are commonly used for Arrhenius plot, but your question was about Arrhenius integral. I misunderstood your question. This is beyond of my expertise.
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