June 19, 2019, 11:19:39 PM
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Topic: Determining the pi to pi antibonding UV absorptions?  (Read 286 times)

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Offline AussieKenDoll

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Determining the pi to pi antibonding UV absorptions?
« on: March 18, 2019, 02:30:19 PM »
How do I find out if a compound expected to have pi to pi antibonding absorptions in the 200-400 nm range, just by looking at the formula of the compound?

Offline Mitch

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Re: Determining the pi to pi antibonding UV absorptions?
« Reply #1 on: March 18, 2019, 03:02:19 PM »
Does it have pi-bonds?
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Offline AussieKenDoll

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Re: Determining the pi to pi antibonding UV absorptions?
« Reply #2 on: March 18, 2019, 03:34:43 PM »
Is having a pi bond make a compound has a pi to pi antibonding uv absorption?

Offline Babcock_Hall

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Re: Determining the pi to pi antibonding UV absorptions?
« Reply #3 on: March 18, 2019, 04:14:50 PM »
I may be going on a tangent, but do you know what conjugated pi bonds are?  There is a relationship between the number of conjugated pi bonds and the wavelength.

Offline AussieKenDoll

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Re: Determining the pi to pi antibonding UV absorptions?
« Reply #4 on: March 18, 2019, 05:03:30 PM »
yea i know about conjugated pi bonds! What is that relationship?

Offline Babcock_Hall

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Re: Determining the pi to pi antibonding UV absorptions?
« Reply #5 on: March 18, 2019, 07:38:14 PM »
The difference in energy falls as the number of conjugated bonds increases.

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