sp³d² Hybridization

In this case, one s, three p and two d-orbitals get hybridized to form six sp³d²hybrid orbitals which adopt octahedral arrangement as given in fig.1.26.

fig 1.26 - Six sp³d² hybrid orbitals

Geometry of SF

₆ molecule

The geometry of SF₆ molecule can be explained on the basis of sp³d² Hybridization. In SF₆ the central sulphur atom has the ground state configuration, 3s²3p⁴ as shown in fig.1.27 (a).

fig 1.27 - Formation of SF₆ molecule involving sp³d² Hybridization

To account for the hexavalency in SF₆ one electron each from 3s and 3p orbitals is promoted to 3d orbitals as shown in fig.1.27(b). These six orbitals get hybridised to form six sp³d²hybrid orbitals. Each of these sp³d² hybrid orbitals overlaps with 2p orbital of fluorine to form S-F bond.

Thus, SF₆ molecule has octahedral structure as shown in fig.1.28. The dotted electrons represent electrons from F-atoms.

fig 1.28 - Octahedral geometry of SF₆ molecule