Type (A): n/d-3-3-3-3-3, Type (B): 3-3-3-3-3, Type (C): 4-3-3-3-3, Type (D): 3-3-3-3-3, Type (E): 2n/d-4-3-3
The only n-gonal convex member of this family is the Johnson Solid hebesphenomegacorona or the "Digonal Hebe-spheno-mega-corona" with n=2. If n=3 then in terms of convexity the resulting Triangular Hebe-spheno-mega-corona is the limiting case as it contains coplanar faces. A regular and convex Diminished Triangular Hebe-spheno-mega-corona can be created by removing the pentagonal pyramids with Type(D) vertices at their apices and replacing them with pentagons, this Johnson Solid is more commonly known as the Hebesphenorotunda.
As was mentioned above, the family is locally convex in the range 2 <= n/d < 3. The local convexity is evident on this 7/3 hebe-spheno-mega-corona with only one rotation around the symmetry axis. In order for the hebe-spheno-mega-corona to exist then 2n/d must be coprime, this implies that d must be odd. This means for d=3 the only locally convex members of the family are those with n/d=7/3 and n/d=8/3.
The solids have a number of internal
vertices. The type (C) vertices are not normally visible from the
outside of the solid.
7/3 | 8/3 |
Hebe-spheno-mega-coronoids
A list of hebe-spheno-mega-coronoids
generated to date is as follows:
5/2 | 9/4 | 11/4 |
Isomorphs
Again there appear to be
additional isomorphs to the hebe-spheno-mega-coronas and -coronoids. These
have not been classified but two examples of isomorphs to the 7/3
hebe-spheno-mega corona are isomorph1 and isomporph2.