(LM25) Valence Bond Theory

  • Valence Bond Theory (VB) describes a covalent bond as the overlap of half-filled atomic orbitals, where a shared pair of electrons forms a bond between two atoms

Valence Bond Theory – Atoms First / OpenStax

  • Sigma Bonds - bonds occur when the electron density is along the axis between the two atoms in the bond.

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  • Pi Bonds - bonds occur when the electron density is off  the axis formed between the two atoms in the bond.

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  • single bond = 1 sigma

  • double bond = 1 sigma & 1 pi

  • triple bond = 1 sigma & 2 pi

  • hybrid orbit - mixture of orbits

    • sp , sp³, sp² etc.

    • can only form sigma bonds

    • will contain s orbitals

  • Hybridization is the mixing of atomic orbitals to create new hybrid orbitals that can form bonds, providing a better representation of molecular structure.