Question

Calculate the distance between nearest neighbours in Na, NaCl and diamond.

Answer 1

For Na crystal we have Body Centered Structure. So nearest neighbor distance is = 2* radius of sodium atom= ((square root of 3)/2)*Side of cube

For NaCl we have Face Centered structure with edge are occupied by chlorine atom. So nearest neighbor distance is =radius of Na+radius of Cl atom

For Diamond structure we have two interpenetrating Face centered cubic lattice displaced along the body diagonal by one quarter of length. So nearest neighbor distance is =2*radius of carbon atom=((sqrt of 3)/4)*side of cube.

Knowing the above parameter we can easily calculate numerical value of distance.