[Wien] (no subject)

[Stefaan Cottenier]

>I tried to figure that out. I can see that volume V=2 x (a/2)^3. My 
>cell is FCC. But why this relation?
>  
>
Your equation is equivalent to V=1/4*a^3. Check any introductory course 
on crystallography and/or condensed matter physics, and you will learn 
that the *primitive* unit cell of a fcc lattice contains just 1 atom and 
has a volume that is one quarter of the conventional unit cell (which 
looks like a cube) that is usually drawn. WIEN2k gives you the volume of 
the primitive unit cell, which is what matters.

Stefaan


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