REGULAR-PRISM

A third permutation group of the graph of cyclopropane obtains if the regular prism discussed as a model for (a) is subjected to rotations as well as to reflections which leave it invariant. The six vertices are thus subject to a permutation group of order 12. We call it the extended group of the stereoformula. Its cycle index is... 

Incidentally, the regular prisms and the regular antiprisms are also semiregular, i.e., Archimedian, solids. Moreover, the second prism, in its most symmetrical configuration, is a regular solid, the cube and the first antiprism, in its most symmetrical configuration, is also a regular solid, the octahedron. 

In the regular prism, horizontal intersections parallel to the base can be prepared by further diluting the selected solvents with solvent of zero strength (represented by the line from Ps to P/ in Fig. 4.17). All points on the obtained triangles represent the same solvent strength, while all points on a vertical straight line correspond to the same selectivity points (Ps). 

The representation for this type of complex system would be a regular prism with ABC as the base and the height D. The specific relations can be shown as a series of ternary systems (ABC) to which a constant amount of D has been added (1 % D, 2 % D, 3 % D,. .., 10 % D, etc.), all carried out in a constant amount of E and F. Boundaries of single homogeneous phases may be easily delineated but composition and number of phases in multiphase regions is difficult to determine. 

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