snub disphenoid

plural snub disphenoids

1. A non-regular convex polyhedron that has 12 equilateral triangles as faces and 18 edges and is a Johnson solid.

   In this structure-type, the eight-coordinate polyhedra (snub disphenoids) share edges to form a framework composed of cross-linked chains that extend along the [100] and [010] directions.

   2006, Andrew J. Locock, “Chapter 6: Crystal chemistry of actinide phosphates and arsenates”, in Sergey Krivovichev, Peter Burns, Ivan Tananaev, editors, Structural Chemistry of Inorganic Actinide Compounds, page 225

   2 more examples

   For the snub disphenoid, our existence proof used the intermediate value theorem in the real numbers to argue that as AB decreases and CD increases there is a point where they become equal.

   2005, Robin Hartshorne, Geometry: Euclid and Beyond, page 457

   Thus, at a basic level this activity is about exploring such polyhedra, starting with the regular cases of the tetrahedron, octahedron, and icosahedron and moving into other solids like the triangular dipyramid and snub disphenoid.

   2013, Thomas Hull, Project Origami: Activities for Exploring Mathematics, 2nd edition, page 153

   Synonyms: Siamese dodecahedron, dodecadeltahedron