Does the diffusion limited rate end up in RMG's output?

[alongd]

Bug Description

Running a liquidReactor simulation, I get library reactions with rate coefficients that seem to be too high and not diffusion limit corrected (the library has gas phase kinetics).

Looking at get_effective_rate in rmgpy.kinetics.diffusionLimited, I see it's used in Reaction.get_rate_coefficient() and in Reaction.fix_diffusion_limited_a_factor. The later isn't used by RMG. My understanding is that we get the corrected rate coefficient for the RMG simulation, but we output (Chemkin/RMS/Cantera) the non-diffusion-limit-corrected rate.

Expected Behavior

I would expect that all rates RMG outputs for a liquid phase simulation, whether from families or libraries, will be capped at the diffusion limit.

[mjohnson541]

RMS handles this by independently estimating the diffusivities identically to RMG and computing the correct diffusion corrected rate. As far as I'm aware Chemkin and Cantera aren't currently capable of doing diffusion corrections. The reason we don't refit is that the diffusivity is dependent on solvent viscosity (so you would need a different file for every solvent of interest) and that refitting these rates to Arrhenius might be tricky I think some of them may not look very Arrhenius after the diffusion correction.

[alongd]

Thanks for the comment!
I'm summarizing our offline discussion and some other thoughts: If we have this information in RMG, we might as well output it, even if that means refitting to a different kinetics form. Since an RMG liq-phase model was generated for a specific solvent, perhaps it's not that terrible to tie the resulting model to a single solvent as well?

[github-actions]

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