The H structure (for Hexagonal) consists of dodecahedra and two additional solids. First are 12-sided shapes consisting of squares, hexagons and pentagons (below right). Second are elongated "barrels" consisting of 12 pentagons and 8 hexagons (below left). The barrels can fit much larger hydrocarbons than methane.
The 4-5-6 faced solids cluster around the middle band of the barrels.
Below we see how the rear faces of one of the 4-5-6 faced solids connect to the barrel behind it.
The two shapes form a sheet of 4-5-6 faced polyhedra enclosing barrels.
The dimples in the sheet surrounded by four pentagons are in turn filled by dodecahedra, which enclose hexagonal holes. The holes fit over the barrels in the sheet below and accept the barrels from the next sheet above.
The oblique view below shows how the sheets stack.
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Created 1 August 2003, Last Update 14 Dec 2009
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