Triangular dipyramid

"For the related molecular geometry see trigonal bipyramid molecular geometry"Infobox face-uniform polyhedron

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Polyhedron_Type=Dipyramid
and
Johnson
J₁₁ - J₁₂ - J₁₃
Face_List=6 triangles
Edge_Count=9
Vertex_Count=5
Symmetry_Group="D"_"3h"
Face_Type=V3.4.4
Dual=triangular prism
Property_List=convex, face-transitiveIn geometry, the triangular dipyramid (or bipyramid) is the first in the infinite set of face-transitive dipyramids. It is the dual of the triangular prism with 6 isosceles triangle faces.

It is also one of the Johnson solids, ("J"₁₂) with equilateral triangle faces. As the name suggests, it can be constructed by joining two tetrahedra along one face. It is a convex deltahedron. Although all its faces are congruent and the solid is face-transitive, it is not a Platonic solid because some vertices adjoin three faces and others adjoin four. As a Johnson solid, with 6 equilateral triangles, it is also in the set of deltahedra.

External links

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** mathworld | urlname = TriangularDipyramid | title = Triangular dipyramid