A question about hexagonal closest packing. ? The answer is b

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1 Answer
Truong-Son N.
May 17, 2018

Kind of an odd question, but all the layers consist of a surface one atom thick, so the distance from #"Co"# atom centers within each layer is equal to the distance between centers of nearest neighbors in adjacent layers.

How I interpreted it is that we first measure the distance from center to center of the 7-atom layers...

https://www.nde-ed.org/

...and then we consider the distance from center to center of the 3-atom layers. This would be the distance from the center of #A# to the center of #A'# (with #A'# above #A#).

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