Sp3 hoga because in solid state pcl5 exist as [pcl4]+ it is cationic form

Hybridisation of the Central Atom in the Cationic form of Solid PCl5

The central atom in the cationic form of solid PCl5 is Phosphorus (P). Phosphorus is bonded to five chlorine atoms in a trigonal bipyramidal geometry.

Hybridisation of Phosphorus Atom
- Phosphorus in PCl5 adopts sp3d hybridization to accommodate the five bonding pairs of electrons.
- In sp3d hybridization, one s orbital, three p orbitals, and one d orbital are combined to form five sp3d hybrid orbitals.
- These sp3d hybrid orbitals are oriented in a trigonal bipyramidal arrangement around the central phosphorus atom.

Explanation of Hybridisation
- The central phosphorus atom undergoes hybridization to maximize the bonding potential with the surrounding chlorine atoms.
- Hybridization allows for the formation of five equivalent sp3d hybrid orbitals, each containing one electron from the chlorine atoms.
- This hybridization results in the formation of strong sigma bonds between phosphorus and chlorine atoms, contributing to the stability of the cationic form of solid PCl5.

In conclusion, the central phosphorus atom in the cationic form of solid PCl5 exhibits sp3d hybridization to accommodate the five bonding pairs of electrons and form stable sigma bonds with the surrounding chlorine atoms.