Bonding and antibonding states of hybridized molecules

Click For Summary

Discussion Overview

The discussion revolves around the concepts of bonding and antibonding states in the context of hybridized molecular orbitals, specifically focusing on whether hybrid orbitals, such as sp or sp2, can exhibit similar bonding and antibonding characteristics as traditional covalent bonds. The scope includes theoretical aspects of molecular orbital theory and valence bond theory.

Discussion Character

  • Debate/contested
  • Technical explanation
  • Conceptual clarification

Main Points Raised

  • Some participants question whether sp hybridized states can have corresponding antibonding states, similar to traditional covalent bonds.
  • One participant asserts that hybrid orbitals are not classified as bonding or antibonding, suggesting that these terms are specific to molecular orbital theory.
  • Another participant challenges this view, asking why molecular orbital theory cannot be applied to hybrid orbitals and whether it fails to explain hybridization.
  • A later reply indicates that bonding and antibonding molecular orbitals can indeed be constructed from hybrid orbitals, noting that the energy of the molecule is independent of whether unhybridized or hybridized atomic orbitals are used.
  • It is mentioned that in valence bond theory, bond energy is influenced by electron localization, which can sometimes be enhanced through hybrid orbitals.
  • Additionally, hybridization is described as a conceptual tool rather than an observable property, with alternative assumptions about hybridization potentially leading to equivalent results.

Areas of Agreement / Disagreement

Participants express differing views on the applicability of molecular orbital theory to hybrid orbitals, with no consensus reached on whether hybrid orbitals can be classified as bonding or antibonding.

Contextual Notes

The discussion highlights the dependence on theoretical frameworks (molecular orbital theory vs. valence bond theory) and the conceptual nature of hybridization, which may not be universally accepted or defined.

Benoit
Messages
33
Reaction score
2
Hey there,

With covalent bonds, we have bonding and antibonding states. If we now have, let's say sp or sp2 states, doesn't matter, is there an equivalent bonding or antibonding state related to this sp bond ? I mean, why sp states wouldn't have antibonding states like every normal covalent bond ?
 
Chemistry news on Phys.org
Hybrid orbitals are neither bonding nor anti-bonding. Thats rather a concept from molecular orbital theory which refers to molecular orbitals, not atomic one.s
 
Ok, but why can't wheuse molecular orbital theory with hybrid orbitals, I don't get why the concept is not the same. Does the molecular orbital theory fails to explain hybrization ?
 
You can construct both bonding and anti-bonding molecular orbitals also from hybrid orbitals. In MO theory, the energy of the molecule will not depend on whether you start from unhybridized atomic or hybridized atomic orbitals. In Valence Bond theory, in contrast to MO theory, the bond energy depends on the localisation of the electrons, and sometimes you can achieve more localisation using hybrid orbitals.
Btw. hybridisation is not some observable property of the atoms in a molecule which we have to explain, but a concept we use to explain the bonding in molecules and often, alternative assumptions about hybridisation lead to equivalent results.
 
  • Like
Likes   Reactions: Benoit

Similar threads

Replies
1
Views
2K
Replies
3
Views
3K
  • · Replies 34 ·
2
Replies
34
Views
5K
  • · Replies 9 ·
Replies
9
Views
3K
Replies
4
Views
2K
  • · Replies 1 ·
Replies
1
Views
2K
Replies
8
Views
2K
Replies
6
Views
3K
  • · Replies 0 ·
Replies
0
Views
2K
  • · Replies 1 ·
Replies
1
Views
4K