ABA

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ABA hcp Hexagonal close packed
ABC ccp cubic close packed
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View of ccp with a hexagonal unit cell
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Relating ccp to fcc
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THESE ARE THE SAME ARRANGEMENTS OF SPHERES !
The arrangement of the spheres is the
sameit is how we choose to describe the unit
cell that is different
ccp in hexagonal unit cell
ccp in fcc unit cell
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Hcp projection where the choice of cell
indicating the hexagonal arrangement
THESE ARE THE SAME ARRANGEMENTS OF SPHERES !

The arrangement of the
spheres is

the sameit is how we
choose to

describe the unit cell that is different
Hcp projection where the choice of cell is
indicating the translational repetition
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The A and B layers of ccp and hcp
Tetrahedral hole
Octahedral hole
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Holes
Octahedral hole
Tetrahedral hole
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ccp in an fcc cell
Octahedral hole
Tetrahedral hole
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hcp
Tetrahedral holes
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hcp
Octahedral holes