The point group of NO₃⁻is C₃v. The reducible representation of NO₃⁻ is 3A'. The molecular orbital diagram of NO₃⁻ shows three occupied p-orbitals and two unoccupied p-orbitals.
The point group of NO₃⁻ is C3v.
The reducible representation of NO3- can be obtained by multiplying the symmetry operations of the point group with the corresponding character table. The resulting reducible representation for NO₃⁻ is
Γ = 2A1 + B1 + E.
The molecular orbital diagram of NO₃⁻ can be drawn as follows
First, draw the molecular orbitals of NO₃⁻ in the same order as the atomic orbitals of NO₃⁻.
The molecular orbitals of NO₃⁻ are formed by the combination of the atomic orbitals of N and O atoms.
The 2s and 2p orbitals of N combine with the 2p orbitals of O to form σ and π bonding and antibonding molecular orbitals.
The resulting molecular orbital diagram of NO₃⁻shows that the highest occupied molecular orbital (HOMO) is a non-bonding orbital with A1 symmetry, while the lowest unoccupied molecular orbital (LUMO) is a π* antibonding orbital with B1 symmetry.