Which d-orbital is involved in `dsp^(2)` hybridisation why ?

Explanation

To determine which d-orbital is involved in dsp² hybridization and why, we can follow these steps:

### Step 1: Understand dsp² Hybridization
Dsp² hybridization occurs in transition metal complexes that exhibit a square planar geometry. This hybridization involves the mixing of one d-orbital, one s-orbital, and two p-orbitals.

### Step 2: Identify the d-Orbital
In the case of dsp² hybridization, the specific d-orbital that is involved is the **dₓ² - y²** orbital. This is because the square planar geometry requires the orbitals to be oriented in a way that allows for maximum overlap with the surrounding ligands.

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