Pi/Sigma bonds clarification

(Polar molecules, Non-polar molecules, etc.)

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Ashley Martinez 1G
Posts: 26
Joined: Fri Apr 06, 2018 11:03 am

Pi/Sigma bonds clarification

Postby Ashley Martinez 1G » Sun Jun 03, 2018 10:34 pm

I understand pi and sigma bonds are caused by an overlap in location between electron dense regions. However I’m having trouble conceptualizing the difference between them, specifically when visualizing them. Does anyone have any tips? Thanks!

Elena 1H
Posts: 27
Joined: Fri Apr 06, 2018 11:04 am
Been upvoted: 1 time

Re: Pi/Sigma bonds clarification

Postby Elena 1H » Sun Jun 03, 2018 10:42 pm

sigma bonds overlap end-to-end and pi bonds overlap side-to-side if that helps

MariahClark 2F
Posts: 60
Joined: Wed Nov 15, 2017 3:04 am

Re: Pi/Sigma bonds clarification

Postby MariahClark 2F » Sun Jun 03, 2018 10:44 pm

The sigma bond is more just like your basic head on covalent bond, where the bond is in line with the bonding orbitals. The pi bond is a covalent bond perpendicular to the bond direction, which is usually in p-orbitals never s. This is why you wouldn't be able to rotate a double or triple bond around its axis like you can with a single bond.

Ashley Martinez 1G
Posts: 26
Joined: Fri Apr 06, 2018 11:03 am

Re: Pi/Sigma bonds clarification

Postby Ashley Martinez 1G » Sun Jun 10, 2018 10:33 pm

I see, that definitely does help. I remember my T.A briefly mentioned that there's a shortcut in identifying which type of bonds exist by memorizing the association between single/double/triple bonds and pi/sigma bonds. Unfortunately, I don't remember exactly what the association was. Does anyone know the association? Thanks!

Alma Flores 1D
Posts: 64
Joined: Wed Nov 08, 2017 3:01 am

Re: Pi/Sigma bonds clarification

Postby Alma Flores 1D » Sun Jun 10, 2018 11:57 pm

There is always one sigma bond in any kind of bond, and additional bonds are pi bonds. A single bond is 1 sigma bond. A double bond is 1 sigma bond and 1 pi bond. A triple bond is 1 sigma bond and 2 pi bonds.


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