When azobenzene is photo-excited to a higher energy configuration, the electron orbital take new energy levels and position's, changing the over all configuration of the molecule.

Now, if various phenyl rings were connected together by an azo bond (R-N=N-R’), what would be the resultant configuration after being photo-excited? In other words, how would the geometry of the new molecule change?

There will be several rotational and twisting energy barrier's imposed unto the molecule, resulting in I imagine really high levels of molecular strain. Would this molecule decompose explosively or would the reaction never happen at all?

I am using azobenzene as an example in this case, but any bond that is subject to this type of transformation would fall in the question

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    $\begingroup$ Do you know that diimide is R-N=C=N-R, quite different then azo? Do you mean to ask what happens if there are various substituents on the rings? Another issue is that names of compounds aren't capitalised. $\endgroup$
    – Mithoron
    Mar 31, 2022 at 18:07
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    $\begingroup$ You see two closevotes and R-N=N-R is azo functional group. Diimide group is just what I wrote. Also this is pretty much a dupe of your earlier question chemistry.stackexchange.com/questions/153803/… $\endgroup$
    – Mithoron
    Mar 31, 2022 at 22:04
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    $\begingroup$ What exactly is "very clear and grounded"? For ex. "various benzene molecules" shouldn't perhaps be derivatives there? There's just one benzene. " how would the configuration result" what configuration? $\endgroup$
    – Mithoron
    Mar 31, 2022 at 22:09
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    $\begingroup$ I apologize If I came forward too hard. Haven’t had the best day today. I’ll edit the question now to see if these adjustments help. The other question you pointed is similar to this one but as you could see it was not answered nor commented on. $\endgroup$ Apr 1, 2022 at 3:00
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    $\begingroup$ You would only have enough energy to isomerise one bond, but in general if molecule is long it may have each bond just a few degrees from the next so could be arched some what. Have a look at carotenes and related molecules in bacteriorhodopsin or photoactive yellow proteins (pyp) to see what the geometry look like before and after isomerisation. $\endgroup$
    – porphyrin
    Apr 3, 2022 at 6:42


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