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Old Mar 15th 2017, 05:44 AM   #1
MatthijsM
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UV absorption by aromatics

Hallo

I'm looking for the theoretical explication why aromatics, so carbon carbon double bounds are able to absorbe UV light.


Sincerely
Matthijs
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Old Mar 15th 2017, 05:28 PM   #2
topsquark
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Originally Posted by MatthijsM View Post
Hallo

I'm looking for the theoretical explication why aromatics, so carbon carbon double bounds are able to absorbe UV light.


Sincerely
Matthijs
Some of this is fact and some information is from my Chem classes oh so long ago and thus is not to be completely trusted.

Fact: In order for a UV photon to be absorbed by a bonded electron we have to have a fairly large band gap for the transition.

Memory: Double carbon bonds are fairly weak. Thus we would likely have a large gap from it to any other bonding level. (I'm trying to check this.)

-Dan
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Last edited by topsquark; Mar 15th 2017 at 05:46 PM.
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Old Mar 16th 2017, 01:41 AM   #3
MatthijsM
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I read somewhere that it is because of conjugated double bounds can you confirm this?
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Old Mar 16th 2017, 02:02 AM   #4
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Thumbs up Important!!!

Download

Khem app from the Samsung Galaxy app store

Or

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