Solid State Question 59
Question: Which of the following metal oxides is anti- ferromagnetic in nature-
Options:
A) $ MnO_2 $
B) $ TiO_2 $
C) $ VO_2 $
D) $ CrO_2 $
Show Answer
Answer:
Correct Answer: A
Solution:
[a] Antiferromagnetism occurs if the alignment of moments is in a compensatory way so as to give zero net moment.For e.g. $ MnO_2 $ All magnetically ordered solids (ferromagnetic and antiferromagnetic solids) transform to the paramagnetic state at some elevated temperatures.
This is most probably due to the randomisation of spins. Antiferromagnetic materials occur commonly among transition metal compounds, especially oxides.Of all given compounds, only $ MnO_2 $ is antiferromagnetic in nature.
Hence, option “A” is the correct answer.