Debunking the Hypervalence Theory: The Truth About Bonds in HClO4

  • Thread starter Thread starter Antozoa
  • Start date Start date
  • Tags Tags
    Structure
AI Thread Summary
In the discussion, the bonding structure of HClO4 is analyzed, highlighting that chlorine (Cl) forms one single bond with an oxygen atom and three dative bonds with the remaining oxygen atoms. However, according to Valence Bond (VB) theory, Cl undergoes hybridization and forms double bonds instead of dative bonds, leading to structural representations that use double lines rather than arrows to indicate bonding. The conversation raises the question of whether VB theory accommodates dative bonds or if they are reinterpreted through hybridization. It is noted that the concept of hypervalence involving d-orbitals in compounds like HClO4 has been discredited since the late 1960s, suggesting that a simpler representation with single bonds and formal charges is more appropriate.
Antozoa
Messages
1
Reaction score
2
TL;DR Summary
In HClO4 Cl forms one single bond
VB theory, Cl is hybridized
In HClO4 Cl forms one single bond with an oxygen and three dative bonds with the other 3 oxygen atoms.
However, according to VB theory, Cl is hybridized and forms double bonds instead of dative bonds.
Then, the structural formula of the molecule never shows arrows as it would if there were dative bonds, but double lines in place of the arrows.
In conclusion, does VB theory accept dative bonds or not? Do they exist or are they explained differently by hybridisation?
 
Chemistry news on Phys.org
The concept of hypervalence by additional double bonds involvin d-orbitals in compounds like HClO4 has been shown to be incorrect already in the end of the 1960ies. Just draw single bonds and corresponding formal charges on the atoms.
 
  • Like
Likes Bystander and dextercioby
Back
Top