Mention one property which is caused due to the presence of F-centre in a solid .

Explanation

To answer the question regarding one property caused by the presence of F-centers in a solid, we can follow these steps:

### Step-by-Step Solution:

1. **Understand F-centers**:
- F-centers are point defects in a crystal lattice where an anion (usually a halide) is missing, and the vacancy is occupied by an electron. This creates a localized negative charge.

2. **Identify the Property**:
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