`[Ni(lgly)_(2)]` shows two stereoisomers. Those are

Options

A. Geometrical
B. Optical
C. Does not show isomerism
D. Both (1) and (2)

Answer

To determine the two stereoisomers of the coordination compound \([Ni(lgly)_2]\), we will follow these steps:

### Step 1: Identify the Coordination Complex
The coordination complex is \([Ni(lgly)_2]\), where \(\text{lgly}\) represents the ligand glycine (NH2CH2COO−). Nickel (Ni) in this complex is in the +2 oxidation state.

### Step 2: Determine the Coordination Number
Nickel typically has a coordination number of 4 in coordination compounds. Since glycine acts as a bidentate ligand (it can coordinate through both the amino nitrogen and the carboxylate oxygen), each glycine ligand will occupy two coordination sites.

### Step 3: Analyze the Geometry
With a coordination number of 4, the possible geometries are tetrahedral and square planar. However, since glycine is a weak field ligand, it will favor a tetrahedral geometry over square planar.

### Step 4: Draw the Tetrahedral Structure
In a tetrahedral arrangement, the two glycine ligands can occupy different positions around the nickel center. The two ligands can be arranged in two distinct ways, leading to stereoisomerism.

1. **Isomer 1**: Both glycine ligands can be positioned such that they are adjacent to each other (cis configuration).
2. **Isomer 2**: The glycine ligands can be positioned opposite each other (trans configuration).

### Step 5: Determine Optical Activity
In tetrahedral complexes, if there is no plane of symmetry and no center of symmetry, the isomers can be optically active. In this case, both isomers of \([Ni(lgly)_2]\) will be optically active because they do not possess a plane of symmetry.

### Conclusion
The two stereoisomers of \([Ni(lgly)_2]\) are:
1. **Cis isomer**: where the two glycine ligands are adjacent.
2. **Trans isomer**: where the two glycine ligands are opposite each other.