Crystal Lattices
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Crystalline solids have a regular and periodically repeating pattern of constituent particles.
The diagrammatical representation of three dimensional arrangements of constituent particles of a crystal in space with each particle depicted as a point is called crystal lattice. o
There are only 14 possible three dimensional lattices and are known Bravais Lattices.
o Each point in a lattice is called lattice point or lattice site.
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Each point in a crystal lattice signifies one constituent particle which can be an atom, a molecule or an ion.
Lattice points are joined together using straight lines to identify the geometry of the lattice.
Unit Cells
Unit cell can be described as the smallest portion of a crystal lattice.