Fluxionality in Deltahedral Boranes

Tetrahedron. No dsd process of any kind is possible since the tetrahedron is the complete graph K4. A tetrahedron is therefore inherently rigid. 

Octahedron. The highly symmetrical octahedron has no degenerate edges and is therefore inherently rigid. 

4-Bicapped square antiprism. This polyhedron has no degenerate edges and therefore is inherently rigid. 

Edge-coalesced icosahedron. The four edges of the type 56(45) are degenerate. This 11-vertex deltahedron is therefore inherently fluxional. 

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G. Fluxionality in Deltahedral Boranes Diamond-Square-Diamond Rearrangements... 

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