## Pi Bonds Cannot Rotate

$sp, sp^{2}, sp^{3}, dsp^{3}, d^{2}sp^{3}$

Inderpal Singh 2L
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### Pi Bonds Cannot Rotate

Why can Pi Bonds not Rotate? I cannot visualize it properly.

Leo Naylor 2F
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### Re: Pi Bonds Cannot Rotate

Pi bonds cannot rotate because they are p-orbitals overlapping side-by-side, so that both electron density areas are "touching." Hope this helps.

Jagveer 1I
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### Re: Pi Bonds Cannot Rotate

To add on, for the molecule to rotate about the double bond, the π-bond would need to break and then reform. It is not possible for a π-bond to remain intact and rotate.

SahajDole_1C
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### Re: Pi Bonds Cannot Rotate

Pi bonds cannot rotate because the p orbitals overlap and cause a double bond which is more stronger and thus it cannot rotate

Melis Kasaba 2B
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### Re: Pi Bonds Cannot Rotate

For a pi bond, there has to be a parallel orientation of the p orbitals so they overlap. If the bond were to rotate, that would break it.

BKoh_2E
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### Re: Pi Bonds Cannot Rotate

105618850
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### Re: Pi Bonds Cannot Rotate

Pi bonds overlap parallel to one another meaning that rotation is not possible. If there was any form of rotation, the bond would be broken as a result.

Navdha Sharma 3J
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### Re: Pi Bonds Cannot Rotate

Pi-bonds overlap side-by-side. If they rotate, they will break. Hence, pi bonds do not rotate.

Annette Fishman
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### Re: Pi Bonds Cannot Rotate

Rotation around a single bond occurs readily, while rotation around a double bond is restricted. The pi bond prevents rotation because of the electron overlap both above and below the plane of the atoms.

Jason Knight - 1F
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### Re: Pi Bonds Cannot Rotate

Pi bonds are present in double and triple bonded molecules. For example, a double bond has one pi bond and a triple bond has two pi bonds. Pi bonds cannot rotate because that would require the break of the parallel orientation of the p-orbitals.

apurva-3E
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### Re: Pi Bonds Cannot Rotate

They cannot rotate because there are p orbitals overlapping side by side. Try to visualize this in your head after looking at a picture of the pi bond.

David Y
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### Re: Pi Bonds Cannot Rotate

if the bond were to rotate it would break because they are parallel

Chance Herbert 3A
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### Re: Pi Bonds Cannot Rotate

I remember in Dr. Lavelle's lecture on types of bonds he held a marker in his hands parallel to demonstrate how pi bonds do not allow for rotation. If rotation were to occur, the bond would have to be broken which was represented by the marker falling from his hands. I am totally visual as well and I feel like this video gives a great representation if you are still struggling! Hope this helps! https://www.youtube.com/watch?v=7tH8Xe5u8A0
Last edited by Chance Herbert 3A on Sun Dec 06, 2020 4:49 pm, edited 1 time in total.

Tatyana Bonnet 2H
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### Re: Pi Bonds Cannot Rotate

They don't rotate because they are connected side by side, if one atom were to rotate they would no longer be side to side breaking the pi bond. Therefore, pi bonds keep a structure in its plane unless broken.

Joel Meza 3I
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### Re: Pi Bonds Cannot Rotate

This picture does a pretty good job at showing how a pi bond would break.

Nathaly Cruz 2D
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### Re: Pi Bonds Cannot Rotate

When rotating, would the pi bond break because it is no longer parallel?

Caelin Brenninkmeijer 1G
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### Re: Pi Bonds Cannot Rotate

Nathaly Cruz 2D wrote:When rotating, would the pi bond break because it is no longer parallel?

Correct! Pi bonds don't allow atoms to rotate, so if the atom is no longer parallel, there is no pi bond. This is because pi bonds have electron densities on each side of the internuclear axis, preventing the bond to exist if the atoms bonded are not 180º.

David Facio 1K
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### Re: Pi Bonds Cannot Rotate

Think of it like the base you make when you lock arms with another person to give your friend a boost over a fence. If one of the persons serving as the base tried rotating their arms, it would be less stable, and under pressure, the base would break. Similarly, Pi bonds can't rotate, or else they'd simply break.

LovepreetSran_3H
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### Re: Pi Bonds Cannot Rotate

Pi-bonds overlap in a parallel, making it unable to rotate.

Hannah Lechtzin 1K
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### Re: Pi Bonds Cannot Rotate

Pi bonds rely on two p orbitals overlapping side by side. Think of two figure eights overlapping long side to long side. If one of those two figure eights were to turn, then they would no longer overlap side to side. If this occurs with two p-orbitals the bond breaks so pi bonds cannot rotate.

Gian Boco 2G
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### Re: Pi Bonds Cannot Rotate

In a pi bond orbitals are overlapping outside of the intermolecular axis. Thus, rotating the bond about that axis would break the pi bond. On the other hand, sigma bonds overlap along this axis and thus allowing rotation.

Charlie Russell 2L
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### Re: Pi Bonds Cannot Rotate

The two p-orbitals overlap. Think of a LADDER. You cannot move 1 ring of the ladder without moving the other unless you break it (the bond breaks).

Nathaly Cruz 2D
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### Re: Pi Bonds Cannot Rotate

Caelin Brenninkmeijer 1H wrote:
Nathaly Cruz 2D wrote:When rotating, would the pi bond break because it is no longer parallel?

Correct! Pi bonds don't allow atoms to rotate, so if the atom is no longer parallel, there is no pi bond. This is because pi bonds have electron densities on each side of the internuclear axis, preventing the bond to exist if the atoms bonded are not 180º.

Thank you for the explanation :)

America Ramirez 3H
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### Re: Pi Bonds Cannot Rotate

you basically have two regions of the p-orbital overlapping and you cant rotate one without rotating another and thus breaking the pi bond.