Which of the following complex compound exhibits geometrical isomerism?

Options

A. `[Fe(DMG)_(2)]`
B. `[Be(gly)_(2)]`
C. `[PdClBr(gly)]^-`
D. `[Cd(NH_(3))Cl(gly)]`

Explanation

To determine which of the following complex compounds exhibits geometrical isomerism, we need to analyze each compound's structure and the arrangement of its ligands around the central metal atom. Geometrical isomerism occurs when ligands can be arranged differently in space, leading to distinct isomers.

### Step-by-Step Solution:

1. **Understanding Geometrical Isomerism**:
- Geometrical isomerism arises when ligands can occupy different positions around a central metal atom, creating different spatial arrangements. This is often seen in square planar and octahedral complexes.

2. **Analyzing the First Compound: [Fe(DMG)₂]**:
- The complex contains iron (Fe) with DMG (dimethylglyoxime) ligands.
- Iron typically exhibits octahedral geometry with DMG as a bidentate ligand.
- In an octahedral complex, if the two DMG ligands are positioned on opposite sides (trans) or adjacent (cis), geometrical isomers can form.
- Therefore, this compound can exhibit geometrical isomerism.

3. **Analyzing the Second Compound: [Be(Gly)₂]**:
- Beryllium (Be) with glycine (Gly) ligands typically forms a tetrahedral complex.
- In tetrahedral geometry, all ligand positions are equivalent, and there are no distinct arrangements.
- Thus, this compound does not exhibit geometrical isomerism.

4. **Analyzing the Third Compound: [Pd(Cl)(Br)(Gly)]**:
- Palladium (Pd) with chloride (Cl), bromide (Br), and glycine (Gly) ligands can form a square planar complex.
- In a square planar complex, different arrangements of the ligands can lead to geometrical isomers (e.g., Cl and Br can be adjacent or opposite).
- Hence, this compound can exhibit geometrical isomerism.

5. **Analyzing the Fourth Compound: [Cd(NH₃)(Cl)(Gly)]**:
- Cadmium (Cd) with ammonia (NH₃), chloride (Cl), and glycine (Gly) also forms a tetrahedral complex.
- Similar to the second compound, the tetrahedral arrangement does not allow for different spatial arrangements of the ligands.
- Therefore, this compound does not exhibit geometrical isomerism.

### Conclusion:
The complexes that exhibit geometrical isomerism are:
- [Fe(DMG)₂]
- [Pd(Cl)(Br)(Gly)]

### Final Answer:
The complex compounds that exhibit geometrical isomerism are [Fe(DMG)₂] and [Pd(Cl)(Br)(Gly)].