In a crystalline solid, atom of A form fcc packing and atoms of B occupy all octahedral voids. If all the atoms along one body diagonal are removed then what will be the simplest formula of the crystalline solid ?

Explanation

To find the simplest formula of the crystalline solid after removing atoms along one body diagonal, we can follow these steps:

### Step 1: Determine the number of atoms in the unit cell
In a face-centered cubic (FCC) lattice:
- Each corner atom contributes \( \frac{1}{8} \) of an atom to the unit cell.
- There are 8 corners, so contribution from corners = \( 8 \times \frac{1}{8} = 1 \) atom.
- Each face-centered atom contributes \( \frac{1}{2} \) of an atom to the unit cell.
- There are 6 faces, so contribution from faces = \( 6 \times \frac{1}{2} = 3 \) atoms.
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