The inner orbital complex which exhibits both geometrical as well as optical isomerism.

Options

A. `[Cr(en)_(3)]^(3+)`
B. `[IrF_(3)(H_(2)O)_(2)(NH_(3))]`
C. `[NiCl_(2)(en)_(2)]`
D. `[Co(CN)_(2)(o x)_(2)]^(3-)`

Answer

To solve the question regarding the inner orbital complex that exhibits both geometrical and optical isomerism, we can follow these steps:

### Step 1: Understanding Isomerism
- **Geometrical Isomerism**: This occurs when ligands can be arranged in different spatial orientations around the central metal ion. The two main types are cis (same side) and trans (opposite sides).
- **Optical Isomerism**: This occurs when a complex can exist in two non-superimposable mirror images, which means it lacks a plane of symmetry.

### Step 2: Identifying Inner Orbital Complexes
- An inner orbital complex is formed when the d-orbitals of the central metal ion are involved in hybridization. This typically occurs with transition metals in lower oxidation states, where the d-orbitals are filled and can participate in bonding.

### Step 3: Analyzing the Given Complexes
1. **Chromium Ethylenediamine Complex**:
- This complex does not exhibit geometrical isomerism due to the lack of different types of ligands. It can show optical isomerism because it lacks a plane of symmetry.

2. **Iridium Complex**:
- This complex can show geometrical isomerism (cis and trans) but does not exhibit optical isomerism due to the presence of a plane of symmetry.

3. **Nickel(II) Chloride Ethylenediamine Complex**:
- The trans form does not show optical isomerism due to symmetry. The cis form can show both geometrical and optical isomerism as it lacks a plane of symmetry.

4. **Cobalt Complex**:
- The trans form does not show optical isomerism due to symmetry. The cis form can show both geometrical and optical isomerism as it lacks a plane of symmetry.

### Step 4: Conclusion
- The complexes that can exhibit both geometrical and optical isomerism are the **Nickel(II) Chloride Ethylenediamine Complex** (cis form) and the **Cobalt Complex** (cis form). However, since the question specifically asks for an inner orbital complex, the **Cobalt Complex** is the correct answer as it involves d2sp3 hybridization, indicating it is an inner orbital complex.

### Final Answer
The inner orbital complex which exhibits both geometrical as well as optical isomerism is the **Cobalt Complex (Cobalt(III) with CN and Oxidator)**.

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