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In the fluorite structure if the radius ...

In the fluorite structure if the radius ratio is `(sqrt(3)/(2)-1)` how many ions does each cation touch?

A

`4` anions

B

`12` cations

C

`8` anions

D

No cations

Text Solution

Verified by Experts

The correct Answer is:
B, C
`(r_(o+))/(r_(ɵ)) = sqrt(3/2) - 1 = 0.225`
Hence, it is the limiting case where cation in the void of fcc structure is not distorted.
So, number of cations surrounding the particular cation `= 12`. But at the same time `8` anions (present in `TVs`) touch the particul,ar cation.
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