Chemistry-
General
Easy
Question
In an f cc unit cell, atoms are numbered as shown below. The atoms not touching each other are (Atom numbered 3 is face center of front face)
- 3 and 4
- 1 and 3
- 1 and 2
- 2 and 4
The correct answer is: 1 and 2
In fcc structure, corner atoms do not touch each other (atoms 1 and 2), but every face center atom touches corners. Moreover, every face center atom touched every other face center atom provided it is not the opposite face center atom in an fcc unit cell
1.Atoms 3 and 4 are touching each other where center-to-center distance 
2.Atoms 1 and 2 are not touching each other
Atoms 2 and 4 are touching each other where center-to-center distance
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