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The
Structure of Solids |
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Unit
Cells
· The
choice of a cell is arbitrary. Several different cells could be replicated
throughout space to generate a given lattice. This is shown opposite for
a two dimensional lattice. A is the cell of choice as it exhibits the highest
symmetry. |
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From:
Callister, "Materials Science & Engineering," Wiley (1997), and Blakemore,
"Solid State Physics," Saunders (1974) |
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·
In
three dimensions, the Unit cell is described by three unit vectors (a,
b, c) and three angles (α, β, γ).
· By
convention, when selecting the sides of the unit cell: a
< b < c with a the shortest vector
linking lattice points and b the next shortest vector, etc.. |
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