International
Tables for
Crystallography
Volume C
Mathematical, physical and chemical tables
Edited by E. Prince

International Tables for Crystallography (2006). Vol. C, ch. 1.3, p. 13

Table 1.3.4.2 

E. Kocha

aInstitut für Mineralogie, Petrologie und Kristallographie, Universität Marburg, Hans-Meerwein-Strasse, D-35032 Marburg, Germany

Table 1.3.4.2| top | pdf |
Simulated Laue classes, extinction symbols, simulated `possible space groups', and possible true space groups for crystals twinned by merohedry (type 2)

Twinned crystalSingle crystal
Simulated Laue classTwin extinction symbolSimulated `possible space groups'Possible true space groups
4/mmm P - - - [P422, P4mm,] [P\bar42m], [P\bar4m2,] [P4/mmm] [P4, P\bar4, P4/m]
[P4_2] - - [P4_222] [P4_2, P4_2/m]
[P4_1] - - [P4_122, P4_322] [P4_1, P4_3]
[Pn] - - [P4/nmm] [P4/n]
[P4_2/n] - - [P4_2/n]
I - - - [I422, I4mm, I\bar42m,] [I\bar4m2,] [I4/mmm] [I4, I\bar4, I4/m]
[I4_1] - - [I4_122] [I4_1]
[I4_1/a] - - [I4_1/a]
[\bar3m1] P - - - [P321, P3m1], [P\bar3m1] [P3, P\bar3]
[P3_1] - - [P3_121, P3_221] [P3_1, P3_2]
[\bar31m] P - - - [P312, P31m], [P\bar31m] [P3, P\bar3]
[P3_1] - - [P3_112, P3_212] [P3_1,P3_2]
[\bar3m] R - - [R32, R3m, R\bar3m] [R3, R\bar3]
[6/m] P - - - [P6, P\bar6, P6/m] [P3, P\bar3]
[P6_2] - - [P6_2, P6_4] [P3_1, P3_2]
[6/mmm] P - - - [P622, P6mm,] [P\bar6m2], [P\bar62m,] [P6/mmm] [P3, P\bar3, P321], [P312, P3m1], [P31m, P\bar3m1,] [P\bar31m, P6, P\bar6,] [P6/m]
[P6_3] - - [P6_322] [P6_3, P6_3/m]
[P6_2] - - [P6_222, P6_422] [P3_1, P3_2], [P3_121, P3_221,] [P3_112, P3_212], [P6_2, P6_4]
[P6_1] - - [P6_122, P6_522] [P6_1, P6_5]
P - - c [P6_3mc, P\bar62c,] [P6_3/mmc] [P31c, P{\bar 3}1c]
P - c - [P6_3cm, P\bar6c2,] [P6_3/mcm] [P3c1, P\bar3c1]
[m\bar3m] P - - - [P432,P\bar43m,] [Pm\bar3m] [P23, Pm\bar3]
[P4_2] - - [P4_{2}32] [P2_13]
[Pn] - - [Pn\bar 3 m] [Pn\bar 3]
I - - - [I432, I\bar43m,Im\bar3m] [I23, I2_13, Im\bar3]
Ia - - [Ia\bar3]
F - - - [F432, F\bar43m,] [Fm\bar3m] [F23, Fm\bar3]
Fd - - [Fd\bar3m] [Fd\bar3]
[P2_1/a,b] - - [Pa\bar3]