I think that the OP was referring to ΔH-double dagger, etc. For there to be published values of these quantities, the authors must have performed studies at more than one temperature.
[...] I've seen a few publications that measure reactions rates at different temperatures, and then give values for ΔH≠, ΔG≠, TΔS≠, etc. [...]
Is there a way to use that data to extrapolate reaction rates at other temperatures? [...]
The answer is no, because all ΔH, ΔG and so on depends only on the initial and final states, while reaction rates depend on the hurdles between the initial and final states. The necessary information is not contained in the ΔH, ΔG... of a synthetic equation. If each step of a reaction were known, maybe all ΔH would give a hint.
Yes, I was - my apologies for half-assing the notation.
And yes, these studies are performed at multiple temperatures - Here is one example of what I'm talking about : Benchmark Reaction Rates, the Stability of Biological Molecules in Water, and the Evolution of Catalytic Power in Enzymes
, in particular table 1. They describe how these values are obtained in the introduction:
An alternative approach, used in much of the work described here, is to conduct reactions in sealed quartz tubes (which must be encased in steel bombs to avoid explosions when reactions are conducted in aqueous solution above 260°C) for various time intervals at elevated temperatures and, after cooling, to monitor the integrated intensities of the signals arising from the reactants and products by high-field proton NMR. If substrate disintegration and product formation follow simple first-order kinetics at each temperature (with the second substrate in large excess in reactions that involve more than one substrate), and if rate constants obtained over a range of temperatures yield a linear Arrhenius plot when plotted as a logarithmic function of 1/T (kelvin), then the rate constant (k25°C) at 25°C can be extrapolated.
The values I'm interested were among those collected in this way. So they're calculating rate reactions over multiple temperatures and verifying that they follow Arrhenius kinetics, and using that to extrapolate the k25°C
. Where I'm getting lost is that it seems bizarre to me that you would go through the effort of collecting enough data to extrapolate the reaction rate at 25°C, but not publish enough of that data to allow readers to extrapolate the reaction rate at other temperatures? Unless I'm overlooking something?
I apologize if these questions are a bit muddled or I'm not providing enough information. This is not my main area of expertise, and I'm feeling
a bit muddled now. I really appreciate any guidance you all have.