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1.1.5 Symmetry in Crystals
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Symmetry is an operation which brings the object back to its original confiscation.
- Symmetry elements underlying a point lattice (see the figure)
- Reflection: reflection across a mirror plane
- Rotation: rotation around a crystallographic axis by an angle θ such as 360°/θ is an integer of value 1, 2, 3, 4 and 6 and is referred to as n -fold rotation.
- Inversion: a point at x,y,z becomes its equivalent at (–x,-y,-z)
- Rotation-Inversion: Rotation followed by inversion OR Rotation-Reflection: Rotation followed by reflection
| Figure 1.5 Basic symmetry operations in crystals |
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