Molecular Orbital Theory

Molecular Orbitals are formed by the overlapping of two atomic orbitals of two different atoms. Bonding Molecular Orbitals have lower energy than the individual atomic orbitals, i.e. stable. The opposite is applicable for Anti-bonding Molecular Orbitals. The number of Molecular Orbitals is the same as the number of Atomic Orbitals.

For Bonding Molecular Orbitals ; b = A + B

For Anti-bonding Molecular Orbitals ; a = A - B

1) For every bonding molecular orbital, there is a corresponding anti-bonding molecular orbital.

2) Anti-Bonding Molecular Orbital will be opposite to Bonding Orbital.

3) Bonding Molecular Orbitals will participate in bonding.

4) Generally Anti-bonding Molecular Orbitals are empty.

5) Bonding and Anti-bonding Molecular orbitals can together hold 2 electrons.

Bond Order = (Bonding - Anti-bonding electron )/ 2