Debunking the Hypervalence Theory: The Truth About Bonds in HClO4

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The discussion centers on the bonding structure of HClO4, where chlorine forms one single bond with an oxygen atom and three dative bonds with the remaining oxygen atoms. However, according to Valence Bond (VB) theory, chlorine is hybridized and forms double bonds instead of dative bonds, leading to a structural representation that uses double lines instead of arrows. The validity of dative bonds in VB theory is questioned, with a consensus that hypervalence involving d-orbitals in HClO4 has been disproven since the late 1960s. The conclusion emphasizes the need to represent the molecule with single bonds and appropriate formal charges.

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TL;DR
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?
 
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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.
 
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