Question

The number of parameters that defines a unit cell are

• A. 2
• B. 3
• C. 4
• D. 6

Answer 1

The correct option is D 6

Unit cell is the smallest portion of a crystal lattice which, when repeated in different directions, generates the entire lattice.

These unit cells are figured in different representation. They are
1. Space filling structure
2. Open structure
3. Structure with actual portions of atom

Unit cell can be characterised by 6 parameter; three edges and three angles between edges.


a, b, & c are edges of a unit cell
$\alpha =\text{angles between edges b and c}\beta =\text{angles between edges a and c}\gamma =\text{angles between edges a and b}$