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Question
Answer the following in brief.
How are the spheres arranged in first layer of simple cubic close-packed structures? How are the successive layers of spheres placed above this layer?
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Solution
Simple cubic close-packed structures are obtained by stacking two-dimensional square close-packed layers.
So, the spheres in the first layer are placed adjacent to one another to form two-dimensional square close packing (i.e., AAAA type arrangement). All the spheres of the successive layers are placed exactly above the spheres of the lower layers. This results in perfect horizontal and vertical alignment between the spheres of various layers.
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