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Question 10.7: CALCULATING THE NUMBER OF ATOMS IN A UNIT CELL How many atom...

CALCULATING THE NUMBER OF ATOMS IN A UNIT CELL

How many atoms are in one primitive-cubic unit cell of a metal?

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As shown in Figure 10.22a, a primitive-cubic unit cell has an atom at each of its eight corners. When unit cells are stacked together, each corner atom is shared by eight cubes, so that only 1/8 of each atom “belongs” to a given unit cell. Thus there is 1/8 × 8 = 1 atom per unit cell.

fig 10.22a

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