Which of the following can exhibit geometrical isomerism

Options

A. `[MnBr_4]^(2-)`
B. `[Pt(NH_3)_3Cl]^+`
C. `[PtCl_2. P(C_2H_5)_3]_2`
D. `[Fe(H_2O)_5 NO]^(2+)`

Explanation

To determine which coordination compounds can exhibit geometrical isomerism, we need to consider the conditions under which geometrical isomerism occurs. Geometrical isomerism typically arises in coordination compounds with specific geometries, such as octahedral and square planar complexes, where ligands can be arranged differently around the central metal atom.

### Step-by-Step Solution:

1. **Identify the Coordination Number and Geometry**:
- Geometrical isomerism is most commonly observed in coordination compounds with a coordination number of 4 (square planar) and 6 (octahedral).

2. **Examine the Ligands**:
- For geometrical isomerism to occur, the ligands must be arranged in such a way that there are different spatial arrangements. This usually requires the presence of at least two different types of ligands.

3. **Square Planar Complexes**:
- In square planar complexes (e.g., [Cu(NH3)2Cl2]), the arrangement can be cis (same side) or trans (opposite sides). This can lead to different isomers.

4. **Octahedral Complexes**:
- In octahedral complexes (e.g., [Co(NH3)4Cl2]+), geometrical isomerism can also occur. The arrangement can be facial (fac) or meridional (mer), depending on how the ligands are positioned.

5. **Examples of Compounds**:
- Consider the following examples:
- [Co(NH3)4Cl2] can exhibit geometrical isomerism (fac and mer).
- [Cu(NH3)2Cl2] can exhibit geometrical isomerism (cis and trans).
- [NiCl2(H2O)2] does not exhibit geometrical isomerism as it has identical ligands.

6. **Conclusion**:
- Based on the above analysis, the compounds that can exhibit geometrical isomerism are those with square planar or octahedral geometry and at least two different types of ligands.