The hexagonal lattice or triangular lattice is one of the five twodimensional Bravais lattice types.^{[1]} The symmetry category of the lattice is wallpaper group p6m. The primitive translation vectors of the hexagonal lattice form an angle of 120° and are of equal lengths,
.
The reciprocal lattice of the hexagonal lattice is a hexagonal lattice in reciprocal space with orientation changed by 90° and primitive lattice vectors of length
.
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Honeycomb lattice
The honeycomb lattice is a special case of the hexagonal lattice with a twoatom basis.^{[1]} The centers of the hexagons of a honeycomb form a hexagonal lattice, and the honeycomb lattice can be seen as the union of two offset triangular lattices.
In nature, carbon atoms of the twodimensional material graphene are arranged in a honeycomb lattice.
See also
 Square lattice
 Hexagonal tiling
 Closepacking
 Centered hexagonal number
 Eisenstein integer
 Voronoi diagram
References
 ^ ^{a} ^{b} Rana, Farhan. "Lattices in 1D, 2D, and 3D" (PDF). Cornell University. Archived (PDF) from the original on 20201218.
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