Comparison of VBT and MOT

Similarities between VBT and MOT:

(I) They account for the directional nature of the bond.

(II) Bond results by the overlapping of two orbitals of minimum energy.

(III) Electronic charge persists in between two atomic nuclei in bond formation.

(IV) Atomic orbitals of same energy, and same symmetry overlap to produce strong bonds.

Dis-similarities between VBT and MOT


1.Ineratomic orbital is produced by multiplying, exchanging and combinations of space wave functions of two electrons.

2.Orbitals of bonded atoms cannot lose their identity.

3.Atomic orbitals monocentric.

4.It explains that inert gases have orbital already spin paired, so they have no tendency to form any linkage.

5.Pauli’s exclusion principle decides the spin function combination with wave function as

\underset{\text{Bonding}}{\uparrow\downarrow} \hspace{30mm} \underset{\text{Antibonding}}{\uparrow\uparrow}


6.VBT introduces a special form to explain the presence of ionic character in bond.

7.VBT explains the difference between bonding and antibonding orbitals as following:


\underset{\text{Bonding}}{\uparrow\downarrow} \hspace{30mm} \underset{\text{Antibonding}}{\uparrow\uparrow}

1. Molecular orbitals are formed by of all atomic orbitals from the valency shell of two atoms.

2. Orbitals of bonded atoms lose their individual identity.

3. Molecular orbitals are polycentric

4. Molecular orbital theory explain the non-existence of molecules of inert gases, since number of bonding and antibonding electrons are equal

5. It explains how electrons are originally present in atomic orbitals and are distributed in new molecular orbitals.

6. MOT is not capable or predicting ionic character in a bond.

7. In MOT both bonding and antibonding orbitals can have electron pairs with opposed spins.


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