Methane is one of the most potent greenhouse gases in Earth's atmosphere.I saw a lot of answers related to it but lacks de facto exegesis to it.

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    $\begingroup$ CO2 can absorb too. It is just that their ranges are different. $\endgroup$ Nov 6 '19 at 10:21

Comparing the vibrational spectra of two different molecules is just like wondering why two people do not have the same fingerprints. The simplest answer is that these two molecules are different molecules with different atoms hence their vibration modes are supposed to be different.

IR Spectra of Methane and Carbon dioxide are available in NIST. This is how real spectroscopy looked like before the focus shifted from true science to fancier presentations and instruments became black-boxes. Anyway, all you have to note both methane and carbon dioxide absorb quite strongly in the typical range of infrared light 400 to 3800 $cm^{-1}$. The question of wide range does not arise as you can see from the spectra, their absorption band positions are different. Methane's spectra is more complex just because it has more active vibrations (dipole moment change is non-zero) and one can see the fine rotational structure of methane but carbon's dioxide's rotational lines are not resolved.

carbon dioxide Methane

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    $\begingroup$ Oh, we are no longer doing true science? /s (Seriously, that sentence could do with a more neutral tone ;) ) $\endgroup$
    – Jan
    Nov 6 '19 at 16:55
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    $\begingroup$ Sometime ago, someone asked here if I did not know LaTeX how could I publish in science? My answer was that most of good fundamental science was done when we had type-writers. Sorry to say these days, presentation matters more, I mean the quality of papers and journal covers look more like comic magazines. Just a fews ago, a Wiley journal suggested that we publish a cover, and the price $ 1000 dollars. Angew. Chem. charges $2000 for a cover. $\endgroup$
    – M. Farooq
    Nov 6 '19 at 17:03
  • $\begingroup$ @M.Farooq Ah, that someone was me:) I couldn't agree more about the rest. Although thousand of dollars is a reasonable price for a chance to end up on TOC ROFL $\endgroup$
    – andselisk
    Nov 6 '19 at 17:24
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    $\begingroup$ @andselisk, Now I remember :-)...Excellent examples for those comic cover articles. I dislike the graphical abstract too...what is the point of those cartoons. Wastes so much time in making them. What about $2000 for a cover option in Angew Chem. That is sad. $\endgroup$
    – M. Farooq
    Nov 6 '19 at 17:30

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