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In silicon crystal, Si atoms from fcc ar...

In silicon crystal, `Si` atoms from fcc arrangement where `4` out `8 TVs` are alos occupied by `Si` atoms. `Z_(eff)` of unit cell is

A

`1`

B

`2`

C

`4`

D

`8`

Text Solution

Verified by Experts

The correct Answer is:
D
Since `Si` atom forms `fcc` arrangement, i.e, `Si` atoms a present at the corner and face centre.
`:. Z_(eff)` for `Si` atom for `fcc` arrangement
`= 4 "atom"//"unit cell"`
Number of `TV_(s) = 8` "atoms"/"unit cell"
`:.` Total number of `Z_(eff)` for `Si` atoms
`= ((1)/(8) xx 8) + ((1)/(2) xx 6) + (1 xx 4)`
`8` "atoms"/"unit cell"
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