The SCSE for `[(CoCl)_(6)]^(4-)` complex is 18000 `cm^(-1)`. The `Delta` for `[CoCl_(4)]^(2-)` will be:

Options

A. 18000 `cm^(-1)`
B. 16000 `cm^(-1)`
C. 8000 `cm^(-1)`
D. 2000 `cm^(-1)`

Explanation

To find the value of Δ (the crystal field splitting energy) for the tetrahedral complex \([CoCl_4]^{2-}\) given the SCSE (Stabilization Energy) for the octahedral complex \([(CoCl)_6]^{4-}\) is 18000 cm\(^{-1}\), we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Relationship Between Octahedral and Tetrahedral Splitting Energy:**
The splitting energy for tetrahedral complexes is related to that of octahedral complexes. The general relationship is:
\[ \Delta_t = \frac{4}{9} \Delta_o \]
where \(\Delta_t\) is the tetrahedral splitting energy and \(\Delta_o\) is the octahedral splitting energy.

2. **Identify the Given Value:**
From the problem, we know that:
\[ \Delta_o = 18000 \, \text{cm}^{-1} \]

3. **Calculate the Tetrahedral Splitting Energy:**
Using the relationship from step 1, we can substitute the value of \(\Delta_o\) into the equation:
\[ \Delta_t = \frac{4}{9} \times 18000 \, \text{cm}^{-1} \]

4. **Perform the Calculation:**
First, calculate \(\frac{4}{9} \times 18000\):
\[ \Delta_t = \frac{4 \times 18000}{9} \]
\[ = \frac{72000}{9} \]
\[ = 8000 \, \text{cm}^{-1} \]

5. **Conclusion:**
Therefore, the value of \(\Delta\) for the tetrahedral complex \([CoCl_4]^{2-}\) is:
\[ \Delta_t = 8000 \, \text{cm}^{-1} \]

### Final Answer:
\(\Delta\) for \([CoCl_4]^{2-}\) is \(8000 \, \text{cm}^{-1}\).

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