Hybridisation- II

Hybridisation of Elements involving d Orbitals:

• The elements which contain d orbitals in addition to s and p orbitals form hybrid orbitals with s, p and d orbitals.
• The hybridisation involves either [3s, 3p and 3d] or [3d, 4s and 4p] (as the energies of these orbitals are comparable).
• However, since the difference in energies of 3p and 4s orbitals is significant, no hybridisation involving 3p, 3d and 4s orbitals is possible.

1. sp3d hybridization:

• One s-orbital , three p-orbitals and one d-orbital hybridise to give five degenerate sp3d hybrid orbitals which are then used to form bonds
• the 5 orbitals are directed towards the corners of a trigonal bipyramid
• Orbitals taking part in hybridization: ns, np and nd

Ex: PCl5

P → 1S2, 2S2 2P6, 3S2 3P1x 3P1y 3P1z [Ground State]

P → 1S2, 2S2 2P6, 3S1 3P1x 3P1y 3P1z 3d1 [Ground State]

2. sp3d2 hybridization

One s, three p and two d orbitals are involved in hybridisation to form the 6 degenerate sp3d2 hybrids.

The shape of the molecule would be octahedral

Ex: SF6