For a pure element with a BCC crystal structure, the surface energies per unit area of \( \{100\} \) and \( \{110\} \) free surfaces are \( S_{100} \) and \( S_{110} \), respectively. The ratio, \( \frac{S_{100}}{S_{110}} \), is (rounded off to one decimal place):
For a pure element with a BCC crystal structure, the surface energies per unit area of \( \{100\} \) and \( \{110\} \) free surfaces are \( S_{100} \) and \( S_{110} \), respectively. The ratio, \( \frac{S_{100}}{S_{110}} \), is (rounded off to one decimal place):
Show Hint
Correct Answer: 1.3
Solution and Explanation
The ratio \( \frac{S_{100}}{S_{110}} \) is typically found from experimental data or using theoretical models, and it can be calculated from the surface energy expressions for the respective planes. For BCC crystals, it is known that:
\[ \frac{S_{100}}{S_{110}} \approx 1.4 \] Thus, the ratio is approximately 1.4, which lies within the range of 1.3 and 1.5.
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