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Grade 12Physical Chemistry

please explain me with the help of a clear diagram the number of neighbours, second nearest neighbours and third nearest neighbours(along with their distance from the Na+ atom) of Na+ ion in the FCC crystal structure o Nacl. Please assume the side length of the square is a.

Profile image of Max
9 Years agoGrade 12
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Profile image of Vikas TU
9 Years ago
In NaCl crystal lattice,
Na+ forms the octahederal voids and Cl- forms the FCC.
The first nearest neigbour would be obvious the distance between the face centred atom and at the octahedreal void and that would be at a/2 dstance.
Th second nearest neighbour distance would be from the corner atom to the edge centre at the alternate distance.
The third nearest neighbour would be at the distance from the edge centre to the diagonal face centred atom.