Unit cell
From Online Dictionary of Crystallography
Unit cell
Other languages
Maille élémentaire (Fr). Einheitszelle (Ge);. Celda unidad (Sp); элементарная ячейка (Ru); Cella elementare (It); 単位胞（単位格子） (Ja).
Definition
The unit cell is the parallelepiped built on the vectors, a, b, c, of a crystallographic basis of the direct lattice. Its volume is given by the triple scalar product, V = (a, b, c).
If the basis is primitive, the unit cell is called the primitive cell. It contains only one lattice point. If the basis is non-primitive, the unit cell is a multiple cell and it contains more than one lattice point. The multiplicity of the cell is given by the ratio of its volume to the volume of a primitive cell.
See also
conventional cell
direct lattice
Section 8.1 of International Tables of Crystallography, Volume A