a poem by Dr. James D. Livingston

If carbon can four neighbors please
It gladly forms four sp3's
And once four bonds have been created
It's satisfied - it's saturated

Should it instead three neighbors choose
It forms instead three sp2's
That leaves one p to form a pi
With another p from another guy

When it can only two neighbors seize
It forms two bonds with two sp's
That leaves two p's to form two pi's
A triple bond will then arise

But conjugation in chains or rings
Broad pi delocalization brings
And MO levels spaced so tight
That they absorb some visible light

So if blood is red, blue jeans are blue,
And grass is green, thank sp2!


sp3 orbitals

sp2 orbitals

sp orbitals
(images courtesy of Dr. Jon Neergard)

Learn more about some of the topics mentioned:
Quicktime Movie about orbital hybridization (from the text by Petrucci, Harwood, and Herring), Why grass is green (serious answer) ,Why grass is green (a more humorous take)

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