Schoenflies-Fedorov

Crystal system Synonyms, old names Symbol Geometrical description Symmetry Hermann- Mauguin (Schoenflies- Fedorov) Lattice parameters (lUCr) (edges length, interaxial angles)... 

Table D.6. Schoenflies-Fedorov point group notation ...

Then he came to extending the division of continuous two-dimensional space into the third dimension. He restricted his examinations to polyhedra and found one of the five space-filling parallelohedra, which were discovered by E. S. Fedorov as capable of filling the space in parallel orientation without gaps or overlaps. Fedorov was one of the three scientists who determined the number (230) of three-dimensional space groups. The other two were Arthur Schoenflies and the amateur William Barlow. 

Fedorov, E. von. II. Zusammenstellung der krystallographischen Resultate des Herrn Schoenfiies und der meinigen. [Survey of the crystallographic results of Schoenflies and myself.] Z. Krist. Mineral. 20, 25-75 (1892). 

About 1890. Fedorov, Schoenflies. and Barlow more or less simultaneously showed that for crystals built up from discrete particles in a three-dimensionally ordered manner, there can be no more than 230 different combinations of elements. the 230 space groups. In 1912, on the basis of their key diffraction experiment, which yielded discrete X-ray reflections from a crystal, Laue, Friedrich, and Knipping demonstrated both the periodic construction of crystals from atoms and the wave nature of X rays. 

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