the value of magnetic moment is zero in the case of antiferromagnetic substaence because the domains …….. .

Options

A. get oriented in the direction of the applied magnetic fleid
B. get oriented opposite to the direction to the direction of the appiled magnetic fleld
C. are oppositely oriented with respect to each other without the application of magnetic field
D. cancel out each other 's magnetic moment

Explanation

To solve the question regarding the value of magnetic moment being zero in antiferromagnetic substances, we can break it down into the following steps:

### Step-by-Step Solution:

1. **Understanding Antiferromagnetism**:
- Antiferromagnetic substances are characterized by the arrangement of their magnetic moments. In these materials, adjacent magnetic moments (spins) align in opposite directions.

2. **Magnetic Domains**:
- In an antiferromagnetic material, the magnetic domains are regions where the magnetic moments are aligned. However, in antiferromagnetic substances, these domains are oriented oppositely to each other.

3. **Cancellation of Magnetic Moments**:
- Since the magnetic moments in adjacent domains are oriented in opposite directions, they effectively cancel each other out. This results in a net magnetic moment of zero for the entire material.

4. **Absence of External Magnetic Field**:
- The orientation of these domains occurs even in the absence of an external magnetic field. Therefore, the magnetic moments remain oppositely oriented with respect to each other.

5. **Conclusion**:
- The value of the magnetic moment is zero in antiferromagnetic substances because the domains are oppositely oriented with respect to each other, leading to the cancellation of their magnetic moments.

### Final Answer:
The value of magnetic moment is zero in the case of antiferromagnetic substances because the domains are **oppositely oriented with respect to each other**.

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