My exploration
as to which Archimedean polyhedra can be used as a 'seed' to generate
families with prismatic symmetry which can take various n-gonal
polyhedra as their bases included consideration of the
icosidodecahedron. In this
instance both the pentagonal faces and
the triangular faces can be regarded as the base.
Pentagonal
base
In the
same way that the icosidodecahedron can be regarded as the fusion of
two pentagal
rotundae, the n-gonal pentakis icosidodecahedron pentagonal base
can be
regarded as the fusion of two pentakis rotundae,
although
for
n
<> 5 the name 'icosidodecahedron' is something of a misnomer and
perhaps the term 'n-gonal birotunda' would be more appropriate.
I have
again concentrated my examples to date around n=7.
Variations exist with (i) star polygons as bases, (ii) inverted
pentagonal prisms, (iii) elongated and gyro-elogated forms, (iv)
'ortho' and 'gyro' modes. These have with one exception not been
explicitly
generated as they are easy to create from the pentakis rotundae.
n=7,
everted pyramids
n=7,
everted pyramids
Triangular
base
The
situation here is more complex as these cannot be regarded as
combinations of rotundae. The name of n-gonal pentakis
icosidodecahedron triangular base will have to suffice
until something more appropriate is suggested.
Two examples of
this family have been generated for n=7, with the pentagonal prisms
pointing
outward and inward. Both are highly distorted from the
originating icosidodeahedron. Some star polygon variants have
also been generated. I attempted to make both inverted and
everted models for polygons from
{7/2} to {7/6}. If the eample is not shown below, then I was not
able to generate that variant.
n=7, everted pyramids
n=7,
inverted
pyramids
n=7/2, everted pyramids. May have degenerate vertices.