What is the maximum number of atoms in a hcp crystal structure of an element ?

Explanation

To determine the maximum number of atoms in a hexagonal close-packed (hcp) crystal structure, we follow these steps:

### Step-by-Step Solution:

1. **Understanding the hcp Structure**:
The hcp structure consists of two layers of atoms that are arranged in a hexagonal pattern. Each unit cell contains atoms at specific positions: corners and face centers.

2. **Identifying Atom Positions**:
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