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Question
Which of the following lattices has the highest packing efficiency (i) simple cubic (ii) body-centred cubic and (iii) hexagonal close-packed lattice?
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Solution 1
Hexagonal close-packed lattice has the highest packing efficiency of 74%. The packing efficiencies of simple cubic and body-centred cubic lattices are 52.4% and 68% respectively.
Solution 2
Packing efficiency of:-
Simple cubic = 52.4% bcc = 68% hcp = 74%
hcp lattice has the highest packing efficiency
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