Answer to Question #140494 in Physics for Ankita

Question

Draw neat sketches of unit cells of simple cubic, body centered cubic and face centered cubic crystal structure and calculate the number of atoms inside in each case and comment on its primitive and non - primitive nature

Answer 1

(These red and blue circles are not atoms, they are nodes/parts of atoms shared between neighbor cells)

SC: 1 complete atom (eight 1/8th of shared atoms in each corner), consists of primitive unit cells.

BCC: 2 atoms, consists of primitive unit cells.

FCC: 4 atoms, consists of non-primitive unit cells.