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What are the difference between Bonding Molecular Orbitals and Antibonding Molecular Orbitals?

Answer:

Bonding molecular orbitals (BMO)

• They are formed by the additive effect of the atomic orbitals. f_b = y₁ + y₂ .
• The electron density increases in the region between the nuclei of bonded atoms.
• The electrons present in the bonding orbitals result in an attraction between the two atoms.
  Because of attractive forces involved, these molecular orbitals have lower energy than the atomic orbitals from which they are formed. This is the cause of their greater stability.
• They are formed when the lobes of the combining orbitals have the same sign.
  These molecular orbitals are represented by sigma and pi.

Antibonding molecular orbitals (AMO)

• They are formed by the subtractive effect of the atomic orbitals. f_b = y₁ – y₂
• The electron density decreases in the region between the nuclei of the atoms and it increases in the region away from the inter‐ nuclear region.
• The electrons present in the antibonding molecular orbitals result in the repulsion between the two atoms.
  Because of the repulsive forces involved, these molecular orbitals have higher energy than the atomic orbitals from which they are formed.
• This is the cause of their lower stability, i.e., it does not favor bond formation and that is why the name antibonding.
• They are formed when the lobes of the combining orbitals have opposite sign.
  These molecular orbitals are represented by Sigma* and Pi* .