In a pure Face-Centred Cubic (FCC) lattice, what exact fraction of the unit cell edge length is NOT — Solid State Chemistry Question
Question
In a pure Face-Centred Cubic (FCC) lattice, what exact fraction of the unit cell edge length is NOT covered by the electron clouds of the corner and face-centred atoms?
Answer: C
💡 Solution & Explanation
In FCC, atoms touch along the face diagonal, so $4r=\sqrt{2}a$ and $2r/a=1/\sqrt{2}=0.707$. Along a unit-cell edge, the uncovered fraction is $1-0.707=0.293$.
💬Ask on WhatsApp →
Still have doubts about this question?
Send it to our AI chemistry tutor on WhatsApp — gets answered in minutes