How to prove there is no primitive cell of diamond structure with only one atom?

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dudu1
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How to prove there is no primitive cell of diamond structure with only one atom?

Thanks in advance!
 
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What is primitive cell?

I know that you know the definition of primitive cell. Diamond is the fcc structured crystal. So can you think that is there any primitive cell in diamond structure??

First think that if fcc is not a primitive cell then how would diamond?
 
The C atoms in a diamond do not form a primitive lattice, hence the elementary cell has to contain more than one atom. Specifically, a translation which maps a selected C atom onto its neighbour does not map the whole crystal lattice onto itself.
On the other hand, replacing a cell containing two neighbouring atoms by a point will yield a primitive lattice, hence the smallest unit cell possible has to contain two atoms.
 
Yeah,
That was I meant too.
Diamond itself is not a primitive cell but a primitive of diamond can be constructed.