现代无机化学进展课件参考文献2-tiling.pdf
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Nets and Tiling Michael O'Keeffe Introduction to tiling theory
and its lication to crystal nets
Start with tiling in two dimensions.
Surface of sphere and plane
Sphere is two-dimensional. We require only two
coordinates to specify position on the surface
of a sphere:
The coordinates of
Changchun 43.9 N, 234.8 W
Tempe 33.4 N, 121.9 W
As far as we are concerned
Tilings in two dimensions are edge-to-edge
(each edge is common to just two tiles)
In three dimensions face-to-face
(each face common to just two tiles) Three different embeddings of the same abstract tiling
brick wall honeycomb herringbone c2mm p 6mm p2gg Again, two embeddings of the same abstract tiling double brick Cairo tiling
Both h e same symmetry, p 4gm . The Cairo conformation
is the minimum density for equal edges.
Recal