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FCC Crystal Problem

  1. Oct 28, 2008 #1
    1. The problem statement, all variables and given/known data

    Write down the number of nearest neighbours in a FCC structure, calculate the angle between the bonds and the packing fraction.

    2. Relevant equations

    Literally don't know where to start!

    3. The attempt at a solution

    Very confused at the moment. Tried to look up packing fraction in my Solid State texbook - but it isn't there?! Is there another name for it? Can someone point me in the right direction please? :)
     
  2. jcsd
  3. Oct 28, 2008 #2

    Mapes

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  4. Oct 28, 2008 #3
    ok - could someone validate my answer please?

    i got 4 atoms in one crystal,

    the volume of one atom: ( pi * (2^(3/2)) * (a^3) ) / 48

    the volume of the crystal is a^3

    giving a packing fraction of 0.236?
     
  5. Oct 28, 2008 #4

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    Check your math.
     
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