Difference between Primitive and Centered unit cell
Difference between Primitive unit cell and Centered unit cell are in tabular form below.
Primitive unit cell |
Centered unit cell |
1) Primitive unit cell are Those unit cell in which constituent particles are present only at corner. | Centred unit cell Is that unit cell in which constituent particles are present On the corners as well as at the other position. |
2) They are simple cubic unit cells | They are either face centred or body centred unit cell. |
3) In primitive unit cell there are 8 atoms are present at 8 corners. | In face centred unit cell has 8 atom at corners and 6 atom each face and in body centred, there are 8 atoms at corners and 1 atom at centre. |
4) A primitive unit cells associated with a single lattice point in it,are called primitive cells or p-cells. | A centred unit cell with more than one lattice point are reffred as centered unit cells or multi unit cells. |
5) A primitive unit cell is the one in which lattice point are present only at the edges of the unit cells. | A centred unit cell is the one in which there are lattice point present in the unit cell in addition to the lattice points at the edges of the unit cells. |
6) Primitive unit cell is a smallest cell possibly. | Centred unit cell is a not smallest possible cell.
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7) If there is a lattice point at the edge of a cell and thus shared with another cells, it is a counted half. | each corner atoms is the corner atom of another cube Hence the corner atoms are shared among eight unit cells. |