Systematic Absences Flashcards
1
Q
Systematic absences
A
Expected reflections that are too weak to be observed by measurement method, depend on symmetry of position of atoms in the crystal and used to derive space group
2
Q
Specific rotation axes
A
Must fill all space therefore can be rectangles, equilateral triangles, squares or regular hexagons
3
Q
Translations
A
Simple movements in straight line
4
Q
Screw axes
A
Rotation axes combined with translations
5
Q
Glide planes
A
Reflections across mirror planes combined with translations
