Q. For a cubic crystal structure which one of the following relations indicating the cell characteristic is correct?
A) $a \neq b \neq c$ and $\alpha \neq \beta\ and\ \gamma \neq 90^{0}$
B) $a \neq b \neq c$ and $\alpha = \beta = \gamma = 90^{0}$
C) $a = b = c$ and $\alpha \neq \beta \neq \gamma = 90^{0}$
D) $a = b = c$ and $\alpha = \beta = \gamma = 90^{0}$
Explanation
(d) In cubic crystals, the crystal axes are perpendicular to one another ($\alpha = \beta = \gamma = 90^{0}$) and the repetitive interval is the same along the three axes ($a = b = c$).
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Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.