If we are studying FCC in the direct lattice, Why does the length of the cube side in the reciprocal lattice equal to 4*Pi/a Where a is the lattice constant,(adsbygoogle = window.adsbygoogle || []).push({});

a*=|G|=2*Pi/a Sqrt(4) = 4*Pi/a

Where a* is the length of the cube site in reciprocal lattice

Note: this thing is repeated in 2 problems and i wouldn't be able to know the reason.

Prefessor is writing it like this but i can't understand (LOL, he also doesn't know to answer me when i asked him, he's just reading from papers, Silliy Professors)

Any one can explain? thanks

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# Reciprocal Lattice Simple Question

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