posted on Jul, 4 2016 @ 10:44 PM
a reply to: Phage
OK, I finally found it. Forgive me; it's late.
It appears alpha is an experimentally derived constant which is in some dispute. The first row for CO2 indicates a single value, the second both an
alpha and beta value, and the third uses a third-degree polynomial curve with an alpha value. That's not extremely unusual in research. Each is
attempting to fit results to a mathematical model.
I can't honestly answer your question since there is disagreement on the proper model. I can say that I would be surprised if pressure made any
substantial difference on the alpha and beta constants. CO2 is a pretty symmetrical and physically stable molecule, which leads to the observation of
tightly defined absorption spectra lines. Since absorption (and emission) occur when electrons jump between quantified energy levels, any change in
pressure would need to affect those energy levels to affect the constants.
I don't know of a mechanism that can do that with CO2.
To contrast, H2O has a very wide absorption band because in reality there is no pure H2O. What we refer to as H2O is really an ever-changing
combination of H2O, OH-, and H3O+, with hydrogen bonding between molecules. The physical geometry is continually shifting, which continually shifts
energy band levels. In that case, a constant which changes with pressure looks much more likely, since pressure does affect the physical molecular
Eh, that sounds confusing to me and I wrote it, lol. I hope it answers your question though.