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To draw a crystal structure you will need to know:

1.Crystal system
2.Lattice type
3.Motif







If you are asked to draw an accurate scale model,
you will need to know the lattice parameters.
To draw a crystal structure you will need to know:

1.Crystal system: cubic
2.Lattice type:  F
3.Motif  Zn @ (0,0,0)
     S @ (¼,¼,¼)







If you are asked to draw an accurate scale model,
you will need to know the lattice parameters.
a = b = c = 5.42Å   α = β = γ = 90°
Step 1: Draw a 2 × 2 array of unit cells
We wish to project the structure down the z axis. Since the unit cell is a cube we will be looking on to the x-y plane. The a and b cell parameters are equal and the angle between them is γ = 90°. Hence the projection of the unit cell will be square.
X Y Z b a γ = 90°
Step 2: Add the lattice points
The lattice type is F so there are lattice points at the corners of the unit cell and at the centres of each face. Add a slight dot to the sketch to show the position of the lattice points.
First add the lattice points at the corners of each cell.
Labels specify the height of the point in the z direction. There is no need to label points at heights 0 and 1.
½
Step 3: Add first atom from motif to each lattice point
The first atom in the motif is Zn at (0,0,0) relative to each lattice point, i.e. we should place a Zn atom on each lattice point.
First add the lattice points at the corners of each cell.
Labels specify the height of the point in the z direction. There is no need to label poibts at heights 0 and 1.
>
Step 4: Add second atom from motif to each lattice point
The second atom in the motif is S at (¼,¼,¼) relative to each lattice point.
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