What is Centred unit cells ?

1.	What is Centred unit cells ?
Answer» When a unit cell contains one or more constituent particles present at positions other than corners in addition to those at corners, it is called a centred unit cell. Centred unit cells are of three types: a. Body-centred unit cells: These unit cells contain one constituent particle (atom, molecule or ion) at its body-centre besides the ones present at its corners. b. Face-centred unit cells: These unit cells contain one constituent particle present at the centre of each face, besides the ones present at its corners. c. End-centred unit cells: In such a unit cell, one constituent particle is present at the centre of any two opposite faces besides the ones present at its corners.

Answer»

When a unit cell contains one or more constituent particles present at positions other than corners in addition to those at corners, it is called a centred unit cell.

Centred unit cells are of three types:

a. Body-centred unit cells: These unit cells contain one constituent particle (atom, molecule or ion) at its body-centre besides the ones present at its corners.

b. Face-centred unit cells: These unit cells contain one constituent particle present at the centre of each face, besides the ones present at its corners.

c. End-centred unit cells: In such a unit cell, one constituent particle is present at the centre of any two opposite faces besides the ones present at its corners.

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