Diamond exists in FCC unit cell with 50% tetrahedral sites also occupied. The effective number of carbon atoms in a unit cell of diamond is

Explanation

To find the effective number of carbon atoms in a unit cell of diamond, we will follow these steps:

### Step 1: Determine the contribution from corner atoms
In a face-centered cubic (FCC) unit cell, there are 8 corners. Each corner atom contributes \( \frac{1}{8} \) of an atom to the unit cell.

\[ \text{Effective number of corner atoms} = 8 \times \frac{1}{8} = 1 \]
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