Electron microscopy
  
P312 (149) Space Group
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Table 1528. P312 (149) space group.

Name in the International Tables for Crystallography
 P312 (The first symbol denotes the lattice type, and the second symbol denotes the three-fold symmetry that is selected to lie parallel to the z axis. The third and fourth symbols indicate that the two-fold rotation axes are perpendicular to the x and y axes.)
Lattice type
 P
Patterson space group
 162
Point group
 32
Crystal system
 Trigonal
Laue class
 -3m
Asymm
 0 ≤ x ≤ 2/3 and 0 ≤ y ≤ 2/3 and 0 ≤ z ≤ 1/2 and x ≤ (1+y)/2 and y ≤ min(1-x, (1+x)/2)
Number of symmetry operators
 6 Absence of reflections

 
Translation
  
Symmetry (atomic coordinates)
X, Y, Z; -Y, X-Y, Z; Y-X, -X, Z; -Y, -X, -Z; Y-X, Y, -Z; X, X-Y, -Z
Remarks
 The perpendicular symmetry elements go between unit cell translations b and c.
Crystal examples
  

 

 

 
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