Write a note on Schottky defect.

Explanation

### Step-by-Step Text Solution on Schottky Defect:

1. **Definition**: The Schottky defect is a type of vacancy defect observed in ionic crystals. It occurs when an equal number of cations and anions are missing from their respective lattice sites in the crystal structure.

2. **Nature of the Defect**: In a Schottky defect, the absence of ions creates vacancies in the lattice. For example, if one cation (positive ion) is missing, there will also be one anion (negative ion) missing. This maintains the overall charge neutrality of the crystal.

3. **Charge Neutrality**: Since the number of missing cations equals the number of missing anions, the electrical neutrality of the crystal remains unaffected. This means that the overall charge of the crystal does not change despite the presence of vacancies.

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