add represented by – node anti-bonding molecular orbital antibonding node atomic orbital bonding molecular orbital atomic orbital 1s 1s σ * σ energy ↿⇂ Fig . Linear Combination of atomic orbitals Unit Unit - - - - . . Bonding in some Homonuclear di-atomic molecules: Molecular orbital diagram of hydrogen molecule (H ) Electronic configuration of H atom is 1s Electronic configuration of H molecule σ s N b – N a Bond order = – Molecule has no unpaired electrons.
Hence, it is diamagnetic . Atomic orbitals of hydrogen Molecular orbitals of H Atomic orbitals of hydrogen Energy s s σ * s σ s Atomic orbitals of lithium Molecular orbitals of Li Fig . MO Diagram for Li molecule Atomic orbitals of lithium Energy s s σ * s σ s Molecular orbital diagram of lithium molecule (Li ) Electronic configuration of Li atom is 1s 2s Electronic configuration of Li molecule σ s , σ * s , σ 2s N b – N a Bond order = – = Molecule has no unpaired electrons. Hence it is diamagnetic .
Atomic orbitals of boron Molecular orbitals of B Atomic orbitals of boron Fig . MO Diagram for B molecule Energy π * py π 2py π 2pz π * pz p x p x p y p y p z p z s s σ * px σ * s σ s σ px Molecular orbital diagram of boron molecule (B ) Electronic configuration of B atom is 1s 2s 2p Electronic configuration of B molecule σ s , σ * s , σ 2s , σ * 2s , π 2py , π 2pz N b – N a Bond order =