Can Hydrogen undergo PI bonding?

In summary, it is not possible for hydrogen to form pi bonds due to its stable configuration with just a single bond and the lack of necessary atomic orbitals. While it is theoretically possible, it is energetically unfavorable and there are rare cases where pi bonds can be formed without sigma bonds.
  • #1
VinnyCee
489
0
I was wondering about Hydrogen and wether or not it can form Pi bonds.
 
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  • #2
I don't think Hydrogen can form Pi bonds.

Since a double bond is made up out of one Sigma and one Pi bond, a Hydrogen atom would need to form a double bond for this to happen.
I don't see any reason why a Hydrogen atom would need to make a double bond since it is nice and stable with just a single bond. A Hydrogen atom only needs 1 additional electron to obtain a Noble gas configuration, so there would be no need for a double bond.
 
  • #3
No, 1s atomic orbitals and pi atomic orbitals don't have the same symmetry, thus they don't interact to form molecular orbitals.
 
  • #4
The only time I have ever seen hydrogens with forming more than 1 bond, if you can call it that, is in things like carborane cages. I'm not sure of the theory behind it, but carboranes are stable structures with hydrogens that have more than 1 bond.
 
  • #5
If you take inorganic chemistry, you'll learn that, basically, any orbital (atomic or molecular) that has the same symmetry as the 1s atomic orbital of the hydrogen can interact (in relevance to group symmetry applications, such as LCAO and the theories). Two pz atomic orbitals, can approach the s orbital from opposite sides and interact with the proper symmetry, more or less covalent. Another example pertaining this subject that gravenewworld has mentioned is the cobaloximes, such as Co[R](dmgH)2(B), where the two dmgH molecules are coordinately bonded to the cobalt in a square planar fashion and are linked together by hydrogen bonds.

http://www.chm.bris.ac.uk/motm/vitaminb12/cobaloximes/CodmgH2RB.gif
 
  • #6
mrjeffy321 said:
Since a double bond is made up out of one Sigma and one Pi bond...

its not always necessary that there be a sigma bond for the formation of a pi bond. the C2 molecule(yes, such a molecule exists), consists of only two pi bonds, making a double bond. however, in most cases a double bond is made up of one sigma and one pi bond, but not in this case.
 
  • #7
If I am not mistaken, the formation of a pi bond requires side on side overlap of the px and py atomic orbitals. Seeing as hydrogen only has a single 1s orbital, it is energetically unfavourable and/or impossible to form a pi bond to hydrogen.
 
  • #8
It is theoretically possible to have a pi-bond to hydrogen, the necessary p-orbitals are there, but they are relatively high in energy. So, I would agree with jer83 that it is energetically unfavorable, although not impossible.

And there are examples of pi bonds without sigma bonds. I saw someone talk about a 4-membered ring system where there was evidence of an interaction of two p-orbitals on atoms at opposite corners of the ring. They referred to it as "banana bonding."
 

1. Can hydrogen undergo PI bonding?

Yes, hydrogen can undergo PI bonding, also known as pi-bonding or pi-interactions. This type of bonding occurs when two atoms share electrons in a pi orbital, which is a type of molecular orbital. Hydrogen can form pi bonds with other elements, such as carbon, nitrogen, and oxygen.

2. What is the difference between PI bonding and covalent bonding?

PI bonding is a type of covalent bonding, which is a type of chemical bond where two atoms share electrons. The main difference is that PI bonding specifically involves the sharing of electrons in a pi orbital, while covalent bonding can involve the sharing of electrons in any type of orbital.

3. How does PI bonding affect the properties of molecules?

PI bonding can affect the properties of molecules in a few ways. First, it can contribute to the stability of a molecule by strengthening the bonds between atoms. Second, it can affect the shape and structure of a molecule, as pi bonds can restrict the rotation of atoms around the bond. Finally, PI bonding can also affect the reactivity of a molecule, as it can influence how easily electrons can be shared or transferred between atoms.

4. Can PI bonding occur between two hydrogen atoms?

No, PI bonding cannot occur between two hydrogen atoms. In order for PI bonding to occur, there must be a difference in electronegativity between the two atoms involved. Since hydrogen has the same electronegativity as itself, it cannot form a pi bond with another hydrogen atom. However, hydrogen can form pi bonds with other elements, as mentioned earlier.

5. How does the strength of PI bonding compare to other types of bonding?

The strength of PI bonding can vary, but in general, it is weaker than other types of bonding such as covalent and ionic bonding. This is because PI bonds involve the sharing of electrons in a less stable orbital compared to other types of bonds. However, PI bonding can still contribute significantly to the overall stability and properties of a molecule.

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