Triangular duoantiprism

The 3-3 duoantiprism is a convex isogonal polychoron that consists of 12 hexagonal antiprisms and 18 tetragonal disphenoids obtained through the process of alternating the 6-6 duoprism. However, it cannot be made uniform.

Vertex coordinates
The vertices of a 3-3 duoantiprism, assuming that the octahedra are regular of edge length 1, centered at the origin, are given by:
 * (0, $\sqrt{3}$/3, 0, $\sqrt{3}$/3)
 * (0, -$\sqrt{3}$/3, 0, -$\sqrt{3}$/3)
 * (0, $\sqrt{3}$/3, ±1/2, -$\sqrt{3}$/6)
 * (0, -$\sqrt{3}$/3, ±1/2, $\sqrt{3}$/6)
 * (±1/2, -$\sqrt{3}$/6, 0, $\sqrt{3}$/3)
 * (±1/2, $\sqrt{3}$/6, 0, -$\sqrt{3}$/3)
 * (±1/2, $\sqrt{3}$/6, ±1/2, $\sqrt{3}$/6)
 * (±1/2, -$\sqrt{3}$/6, ±1/2, -$\sqrt{3}$/6)