the fascination of crystals and symmetry...international tables for crystallography, volume a...
TRANSCRIPT
The Fascination of Crystals and Symmetry
Unit 4.6
by Frank Hoffmann & Michael Sartor
Space Groups and the International Tables
International Tables for Crystallography
International Tables for CrystallographyVolume A: Space-group symmetry
Edited by Th. Hahn
http://img.chem.ucl.ac.uk/sgp/mainmenu.htm
“the crystallographers’ bible”
International Tables for Crystallography, Volume A
Systematic listing of the 17 plane groups and 230 space groups
Space group symbol in short and full notation as well as an unique #
Indication of the crystal system and the crystal class in both systems of nomenclature (H.-M. and Schoenflies)
Diagrams of the position of the SEs
General position diagram
Listing of all SOs as coordination transformations
Multiplicity, Wyckoff letters, Site symmetry
…and some more (“incomprehensible”) things
group theory / X-ray diffraction
International Tables for Crystallography – Space group Pmm2
Header
Space group Pmm2 – Header
Pmm2
Number Full symbol
Crystal class C2v mm2 Crystal system OrthorhombicShort symbol
No. 25
1
Patterson Symmetry PmmmPmm2
Schoenflies H.-M.
International Tables for Crystallography – Space group Pmm2
Diagram of the Symmetry elements – Space group Pmm2
b
a
horizontal mirror planes
Diagram of the Symmetry elements – Space group Pmm2
b
avertical mirror planes
Diagram of the Symmetry elements – Space group Pmm2
b
a
2-fold axes of rotation
International Tables for Crystallography – Space group Pmm2
General Position Diagram – Space group Pmm2
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General Position Diagram – Space group Pmm2
General Position Diagram – Space group Pmm2
an atom on a general position(does not sit on a SE)
General Position Diagram – Space group Pmm2
General Position Diagram – Space group Pmm2
General Position Diagram – Space group Pmm2
General Position Diagram – Space group Pmm2
General Position Diagram – Space group Pmm2
General Position Diagram – Space group Pmm2
General Position Diagram – Space group Pmm2
General Position Diagram – Space group Pmm2
General Position Diagram – Space group Pmm2
General Position Diagram – Space group Pmm2
General Position Diagram – Space group Pmm2
General Position Diagram – Space group Pmm2
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, image and mirror image
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position along the c-directionabove the projection plane
of chiral objects
General Position Diagram – Space group Pmm2
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, image and mirror image
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position along the c-directionabove the projection plane
General Position Diagram – Space group Pmm2
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, image and mirror image
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position along the c-directionabove the projection plane