Platonic Molecules - stick and ball models

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Platonic Molecules - stick and ball models, continued

Platonic molecules of high coordination	The Platonic bodies of this page are of high coordination in the center mode. As molecules they are realized only in the cage mode of lower coordination. - This page is a continuation of the previous page.
Normalize and rotate the models	The models are shown in maximal size and might not fit into the window. Decrease the size of the models by dragging the mouse, right mousekey pressed. Rotate a selected model by dragging the mouse, left mousekey pressed.
Dodecahedron One kind of atoms	The dodecahedron is realized as the molecule dodecahedrane C₂₀H₂₀with the coordination 4 of the carbon atoms, three bonds to neighbouring carbon atoms, one to the external H atom. (The H atoms adjacent to the yellow balls are here not shown explicitely.) - This molecule has the typical properties of high symmetry compounds. It has a meltingpoint of 430C^o which is rather high compared to its less symmetrical isomers. If the temperature is raised, due to its high symmetry the molecule can pick up energy in form of rotations without disrupting the bonds. It rather sublimes than melts.
Dodecahedron Two kinds of atoms Configuration I	If there are two kinds A and B of atoms or complexes forming the cage, additional conditions evolve. As the one way of realization one may consider the case, that each complex A is connected to a neighbouring complex of type B. However, since the number of edges of a face is odd, this is impossible. Thus, a complex A must be able to form bonds as well to complexes of its kind as well as to complexes of the other kind. Naturally, the same requirement holds for the complexes B. - In addition addition to this Configuration I, a Configuration II can be visualized.
Dodecahedron Two kinds of atoms Configuration II	In Configuration I there are binding configurations A[ABB] and A[BBB] for the complexes A and corresponding binding configurations B[BAA] and B[AAA] for the complexes B. In Configuration II there are complete rings of identical complexes. The binding configurations are A[AAB] and A[BBB] for the complexes A and B[BBA] and B[AAA] for the complexes B.
Ikosahedron One kind of atoms	Ikosahedral structures play an important role in the chemistry of boron, e.g. by a reaction of boroydride and diborane: 2[BH₄]^- + 5B₂H₆ ---> [B₁₂H₁₂]^- + 13H₂ The boron atoms at the corners of the ikosahedron are each bound to 5 adjacent boron atoms and to one external hydrogen (not shown in the model) by a terminal B-H bond. The twofold negative charge of the complex may attract metal ions, e.g two K⁺ ions. This ikosahedron may by itself form the center unit for a ikosahedron of 12 surrounding identiacal ikosahedrons.
Ikosahedron Two kinds of atoms Configuration I	Analogue to the dodecahedron, in this Configuration I there are binding configurations A[ABBBB] and A[ABABB] for the complexes A and B[BAAAA] and B[BABAA] for the complexes B.
Ikosahedron Two kinds of atoms Configuration II	Again in analogy the dodecahedron, in this Configuration II there are complete rings of identical complexes. The binding configurations are A[ABBBB] and A[ABABB] for the complexes A and B[BAAAA] and B[BABAA] for the complexes B. It is an interesting challenge, to realize these different configurations chemically!
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