Orthorhombic crystal system

Bravais lattices

There are four orthorhombic Bravais lattices: primitive orthorhombic, base-centered orthorhombic, body-centered orthorhombic, and face-centered orthorhombic.

The primitive cell of the base-centered orthorhombic lattice has the shape of a right rhombic prism; it can be constructed because the two-dimensional centered rectangular base layer can also be described with primitive rhombic axes. Note that the length ${\displaystyle a}$ of the primitive cell below equals ${\displaystyle \frac{1}{2}\sqrt{a^2+b^2}}$ of the conventional cell above.