Valence bond theory was proposed by Linus Pauling and John C. Slater
Valence Bond Theory(VBT)
According to the valence bond theory, electrons in a molecule occupy atomic orbitals rather than molecular orbitals. The atomic orbitals overlap on the bond formation and the larger the overlap the stronger the bond. Linus Pauling proposed this theory, and later supported by slater. This theory describes how molecules form covalent bonds between their atoms.
- A covalent bond is formed by overlapping of valance orbitals or salts containing unpaired electrons with antiparallel spin.
- The strength of overlap determine the strength of bonding between the atoms in the molecule.
- The overlapping of orbitals is always directional.
- The overlapping depends upon the size and energy of the orbitals.
- A sigma bond is formed by the axial overlap of orbitals.
- A π bond is formed by the axial overlap of orbitals.
- Greater is the overlapping of orbitals stronger is the bond and stable is the molecule.