The dsp2 hybridization favours a planar geometry in which the four hybridized orbitals lie in the equatorial xy plane, as in ICl4- or XeF4. So, the dx^2-dy^2 orbital is used in dsp2 hybridization, along with the s, px and py orbitals to form a square planar geometry.

Overview:
In pd hybridization, the orbitals used are a combination of the 4d and 5s atomic orbitals of the central atom. This hybridization occurs in coordination compounds where the central atom is a transition metal, such as palladium (Pd). The resulting hybrid orbitals are known as pd orbitals.

Explanation:
To understand pd hybridization, let's first discuss the concept of hybridization. Hybridization is the process of mixing atomic orbitals to form new hybrid orbitals that are suitable for bonding. It allows for a more accurate description of the molecular geometry and bonding properties of molecules.

In the case of pd hybridization, the central Pd atom has the electron configuration [Kr] 4d^10 5s^0. To form hybrid orbitals, the 4d and 5s orbitals participate in hybridization. The energy of the 4d orbitals is close to that of the 5s orbital, making them suitable for hybridization.

Steps:
The pd hybridization process can be explained in the following steps:

1. Promotion: One electron from the 5s orbital is energetically promoted to the empty 4d orbital. This results in the formation of an excited state with the electron configuration [Kr] 4d^9 5s^1.

2. Hybridization: The excited state now undergoes hybridization, where the 4d and 5s orbitals mix to form four hybrid orbitals. These hybrid orbitals are called pd orbitals and are denoted as pdx, pdy, pdz, and pdz*.

3. Geometry: The pd orbitals arrange themselves in space according to the geometry of the molecule. The most common geometries observed in pd hybridization are square planar and tetrahedral.

4. Bonding: The pd orbitals then participate in bonding with other atoms or ligands. The hybrid orbitals overlap with the orbitals of the ligands, forming sigma bonds. The pd orbitals may also participate in pi bonding if the ligand has pi-acceptor properties.

Conclusion:
In pd hybridization, the 4d and 5s orbitals of the central Pd atom combine to form pd hybrid orbitals. These hybrid orbitals are involved in bonding with other atoms or ligands in coordination compounds. The resulting pd hybridization allows for a more accurate description of the molecular geometry and bonding properties of transition metal complexes.

Pz and Dz2