Which formula is used to calculate edge length $(a)$ in a $bcc$ structure,where $r$ is the radius of the atom?

What are the variables in the graph of powder diffraction pattern of a crystalline solid?

Ionic radii of cation $A^{+}$ and anion $B^{-}$ are $102 \ pm$ and $181 \ pm$ respectively. These ions are allowed to crystallize into an ionic solid. This crystal has cubic close packing for $B^{-}$ and $A^{+}$ is present in all octahedral voids. The edge length of the unit cell of the crystal $AB$ is $pm$.

$A$ metal crystallizes in a simple cubic lattice. The radius of the metal atom is $x \ pm$. What is the volume of the unit cell in $pm^3$?

Calculate the volume of $fcc$ unit cell if the radius of a particle in it is $106.05 \ pm$.

Potassium metal crystallizes in a face-centered cubic $(FCC)$ lattice. If the edge length of the unit cell is $0.574 \ nm$,what is the shortest distance between any two potassium nuclei (in $nm$)?