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Author(s) -
Irran Elisabeth,
Köllisch Klaus,
Leoni Stefano,
Nesper Reinhard,
Henry Paul F.,
Weller Mark T.,
Schnick Wolfgang
Publication year - 2000
Publication title -
chemistry – a european journal
Language(s) - English
Resource type - Reports
SCImago Journal Rank - 1.687
H-Index - 242
eISSN - 1521-3765
pISSN - 0947-6539
DOI - 10.1002/1521-3765(20000804)6:15<2669::aid-chem2669>3.0.co;2-m
Subject(s) - tetrahedron , silicate , surface (topology) , cover (algebra) , crystallography , ideal (ethics) , physics , materials science , topology (electrical circuits) , chemistry , geometry , mathematics , combinatorics , mechanical engineering , astronomy , engineering , philosophy , epistemology
The cover picture shows an illustration of the crystal structure of Ce 4 [Si 4 O 4 N 6 ]O (Ce: red, O: blue, N: green, Si: at the center of the dark green tetrahedra) with a specifically adopted periodic nodal surface (PNS). This infinite hyperbolically corrugated PNS divides the space into two independent sub‐spaces. Topologically, there is no path from the gray to the yellow side of the surface. The hyperbolically corrugated layer structure of condensed Q 3 type SiON 3 tetrahedra in Ce 4 [Si 4 O 4 N 6 ]O extends along the yellow side of the surface with the bonds Si−O piercing the PNS and the [Ce 4 O] 10+ ions situated on the gray side of the surface. Here the application of a periodic nodal surface turns out to be an elegant way for the description of the first hyperbolical layer silicate structure. From a topological point of view the structure of Ce 4 [Si 4 O 4 N 6 ]O is much more complex than the simple situation of an ideal single‐layer silicate with an infinite number of parallel silicate sheets. This work is described in more detail by W. Schnick et al. on p. 2714 ff.