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Difference between revisions of "Primitive cell"

From Online Dictionary of Crystallography

 
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A primitive cell is a [[unit cell]] built on the basis vectors of a primitive basis of the [[direct lattice]], namely a crystallographic basis of the vector lattice '''L''' such that every lattice vector '''t''' of '''L''' may be obtained as an integral linear combination  of the basis vectors, '''a''', '''b''', '''c'''.  
 
A primitive cell is a [[unit cell]] built on the basis vectors of a primitive basis of the [[direct lattice]], namely a crystallographic basis of the vector lattice '''L''' such that every lattice vector '''t''' of '''L''' may be obtained as an integral linear combination  of the basis vectors, '''a''', '''b''', '''c'''.  
  
Its contains only one lattice point and its volume is equal to the triple scalar product ('''a''', '''b''', '''c''').
+
It contains only one lattice point and its volume is equal to the triple scalar product ('''a''', '''b''', '''c''').
  
 
''Non-primitive'' bases are used conventionally to describe ''centred lattices''. In that case, the unit cell is a multiple cell and it contains more than one lattice point. The multiplicity of the cell is given by the ratio of its volume to the volume of a primitive cell.
 
''Non-primitive'' bases are used conventionally to describe ''centred lattices''. In that case, the unit cell is a multiple cell and it contains more than one lattice point. The multiplicity of the cell is given by the ratio of its volume to the volume of a primitive cell.
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=== See also ===
 
=== See also ===
  
 +
[[crystallographic basis]]<br>
 
[[direct lattice]]
 
[[direct lattice]]
  

Revision as of 14:53, 25 January 2006

Primitive cell

Other languages

Maille primitive (Fr). Celda primitiva (Sp).

Definition

A primitive cell is a unit cell built on the basis vectors of a primitive basis of the direct lattice, namely a crystallographic basis of the vector lattice L such that every lattice vector t of L may be obtained as an integral linear combination of the basis vectors, a, b, c.

It contains only one lattice point and its volume is equal to the triple scalar product (a, b, c).

Non-primitive bases are used conventionally to describe centred lattices. In that case, the unit cell is a multiple cell and it contains more than one lattice point. The multiplicity of the cell is given by the ratio of its volume to the volume of a primitive cell.


See also

crystallographic basis
direct lattice

unit cell

Section 8.1 of International Tables of Crystallography, Volume A