A notable, and indeed surprising, feature of the configuration space are the multiple orientation permutations of the component polytopes (see Table ). Fig. shows four orientation permutations of each of the two tetrahedral T-4 species, four orientation permutations of each of the three square planar SP-4 species, and the two orientation permutations of each of the three symmetric linear SL-4 "fusion" species, along with their (ϕ, θ) configuration space coordinates. A key consequence is that, within this frame of reference, not only does any E-mode symmetric stereotropic process involve permutation stereoisomer pseudorotations (e.g., T-4-R ⇌ T-4-S), but also orientation permutations (e.g., the four different relative orientations of T-4-R). Such orientation permutations may be experimentally observable, especially if the B-atoms are distinguishable though this is not strictly required.