ExtinctionSymbolsAndSpaceGroups - ccdc-opensource/dash GitHub Wiki

Appendix F: Extinction Symbols and their Space Groups

In order to use this table look up the extinction symbol returned by the space group determination program, in the left-hand column of the table. The possible space groups for that extinction symbol are then listed in the right-hand columns.
Monoclinic a axis
P - 1 1 P 2 1 1 P m 1 1 P 2/m 1 1
P 21 1 1 P 21 1 1 P 21/m 1 1
P b 1 1 P b 1 1 P 2/b 1 1
P 21/b 1 1 P 21/b 1 1
P c 1 1 P c 1 1 P 2/c 1 1
P 21/c 1 1 P 21/c 1 1
P n 1 1 P n 1 1 P 2/n 1 1
P 21/n 1 1 P 21/n 1 1
C - 1 1 C 2 1 1 C m 1 1 C 2/m 1 1
C n 1 1 C n 1 1 C 2/n 1 1
B - 1 1 B 2 1 1 B m 1 1 B 2/m 1 1
B b 1 1 B b 1 1 B 2/b 1 1
I - 1 1 I 2 1 1 I m 1 1 I 2/m 1 1
I c 1 1 I c 1 1 I 2/c 1 1
Monoclinic b axis
P 1 - 1 P 1 2 1 P 1 m 1 P 1 2/m 1
P 1 21 1 P 1 21 1 P 1 21/m 1
P 1 a 1 P 1 a 1 P 1 2/a 1
P 1 21/a 1 P 1 21/a 1
P 1 c 1 P 1 c 1 P 1 2/c 1
P 1 21/c 1 P 1 21/c 1
P 1 n 1 P 1 n 1 P 1 2/n 1
P 1 21/n 1 P 1 21/n 1
C 1 - 1 C 1 2 1 C 1 m 1 C 1 2/m 1
C 1 c 1 C 1 c 1 C 1 2/c 1
A 1 - 1 A 1 2 1 A 1 m 1 A 1 2/m 1
A 1 n 1 A 1 n 1 A 1 2/n 1
I 1 - 1 I 1 2 1 I 1 m 1 I 1 2/m 1
I 1 a 1 I 1 a 1 I 1 2/a 1
Monoclinic c axis
P 1 1 - P 1 1 2 P 1 1 m P 1 1 2/m
P 1 1 21 P 1 1 21 P 1 1 21/m
P 1 1 a P 1 1 a P 1 1 2/a
P 1 1 21/a P 1 1 21/a
P 1 1 b P 1 1 b P 1 1 2/b
P 1 1 21/c P 1 1 21/b
P 1 1 n P 1 1 n P 1 1 2/n
P 1 1 21/n P 1 1 21/n
B 1 1 - B 1 1 2 B 1 1 m B 1 1 2/m
B 1 1 n B 1 1 n B 1 1 2/n
A 1 1 - A 1 1 2 A 1 1 m A 1 1 2/m
A 1 1 a A 1 1 a A 1 1 2/a
I 1 1 - I 1 1 2 I 1 1 m I 1 1 2/m
I 1 1 b I 1 1 b I 1 1 2/b
Orthorhombic
P - - - P 2 2 2 P m m 2 P m m m
P m 2 m
P 2 m m
P - - 21 P 2 2 21
P - 21 - P 2 21 2
P - 21 21 P 2 21 21
P 21 - - P 21 2 2
P 21 - 21 P 21 2 21
P 21 21 - P 21 21 2
P 21 21 21 P 21 21 21
P - - a P m 2 a
P 21 m a P m m a
P - - b P m 21 b P m 21 b
P 2 m b P m m b
P - - n P m 21 n
P 21 m n P m m n
P - a - P m a 2 P m a m
P 21 a m
P - a a P 2 a a P m a a
P - a b P 21 a b P m a b
P - a n P 2 a n P m a n
P - c - P m c 21
P 2 c m P m c m
P - c a P 21 c a P m c a
P - c b P 2 c b P m c b
P - c n P 21 c n P m c n
P - n - P m n 21
P 21 n m P m n m
P - n a P 2 n a P m n a
P - n b P 21 n b P m n b
P - n n P 2 n n P m n n
P b - - P b m 2
P b 21 m P b m m
P b - a P b 21 a P b m a
P b - b P b 2 b P b m b
P b - n P b 2 n P b m n
P b a - P b a 2 P b a m
P b a a P b a a
P b a b P b a b
P b a n P b a n
P b c - P b c 21 P b c m
P b c a P b c a
P b c b P b c b
P b c n P b c n
P b n - P b n 21 P b n m
P b n a P b n a
P b n b P b n b
P b n n P b n n
P c - - P c m 21
P c 2 m P c m m
P c - a P c 2 a P c m a
P c - b P c 21 b P c m b
P c - n P c 21 n P c m n
P c a - P c a 21 P c a m
P c a a P c a a
P c a b P c a b
P c a n P c a n
P c c - P c c 2 P c c m
P c c a P c c a
P c c b P c c b
P c c n P c c n
P c n - P c n 2 P c n m
P c n a P c n a
P c n b P c n b
P c c n P c c n
P n - - P n m 21 P n m m
P n 21 m
P n - a P n 21 a P n m a
P n - b P n 2 b P n m b
P n - n P n 2 n P n m n
P n a - P n a 21 P n a m
P n a a P n a a
P n a b P n a b
P n a n P n a n
P n c - P n c 2 P n c m
P n c a P n c a
P n c b P n c b
P n c n P n c n
P n n - P n n 2 P n n m
P n n a P n n a
P n n b P n n b
P n n n P n n n
C - - - C 2 2 2 C m m 2 C m m m
C m 2 m
C 2 m m
C - - 21 C 2 2 21
C - - (ab) C m 2 a C m m a
C 2 m b C m m b
C - c - C m c 21 C m c m
C 2 c m
C - c (ab) C 2 c b C m c a
C c - - C c m 21 C c m m
C c 2 m
C c - (ab) C c 2 a C c m b
C c c - C c c 2 C c c m
C c c (ab) C c c a
C c c b
B - - - B 2 2 2 B m m 2 B m m m
B m 2 m
B 2 m m
B - 21 - B 2 21 2
B - - b B m 21 b B m m b
B 2 m b
B - (ac)- B m a 2 B m a m
B 2 c m B m c m
B - (ac)b B 2 c b B m a b
B b - - B b m 2 B b m m
B b 21 m
B b - b B b 2 b B b m b
B b (ac)- B b a 2 B b c m
B b (ac)b B b a b
B b a c
A - - - A 2 2 2 A m m 2 A m m m
A m 2 m
A 2 2 m
A 21 - - A 21 2 2
A - - a A m 2 a A m m a
A 21 m a
A - a - A m a 2 A m a m
A 21 a m
A - a a A 2 a a A m a a
A(bc)- - A b m 2 A b m m
A c 2 m A c m m
A(bc)- a A c 2 a A b m a
A(bc)a - A b a 2 A c a m
A(bc)a a A b a a
A ca a
I - - - I 2 2 2 I m m 2 I m m m
I m 2 m
I 2 2 m
I - - (ab) I m 2 a I m m a
I m 2 b I m m b
I - (ac)- I m a 2 I m a m
I 2 c m I m c m
I - c b I 2 c b I m c b
I(bc)- - I b m 2 I b m m
I c m 2 I c m m
I c - a I c 2 a I c m a
I b a - I b a 2 I b a m
I b c a I b c a
F _ _ _ F 2 2 2 F m m 2 F m m m
F m 2 m
F 2 m m
F _ d d F 2 d d
F d _ d F d 2 d
F d d _ F d d 2
F d d d F d d d
Tetragonal
P - - - P4 P-4 P4/m P 4 2 2 P 4 m m P -4 2 m P4/m m m
P -4 m 2
P - 21 - P 4 21 2 P -4 21 m
P 42 - - P42 P42/m P 42 2 2
P 42 21 - P 42 21 2
P 41 - - P41 P 41 2 2
P43 P 43 2 2
P 41 21 _ P 41 21 2
P 43 21 2
P - - c P 42 m c P -4 2 c P42/m m c
P - 21 c P -4 21 c
P - b - P 4 b m P -4 b 2 P4/m b m
P - b c P 42 b c P42/m b c
P - c - P 42 c m P -4 c 2 P42/m c m
P - c c P 4 c c P4/m c c
P - n - P 42 n m P -4 n 2 P42/m n m
P - n c P 4 n c P4/ m n c
P n - - P4/n P4/n m m
P 42/n - - P42/n
P n - c P42/n m c
P n b - P4/ n b m
P n b c P42/n b c
P n c - P42/n c m
P n c c P4/n c c
P n n - P42/n n m
P n n c P4/n n c
I - - - I4 I-4 I4/m I 4 2 2 I 4 m m I -4 2 m I4/m m m
I -4 m 2
I 41 - - I41 I41 2 2
I - - d I 41 m d I -4 2 d
I - c - I 4 c m I -4 c 2 I4/m c m
I - c d I 41 c d
I 41/a - - I41/a
I a - d I41/a m d
I a c d I41/a c d
Trigonal
P - - - P3 P-3 P3 2 1 P3 m 1 P-3 m 1 P3 1 2
P3 1 m P-3 1 m
P 31 - - P31 P31 2 1
P31 1 2
P32 P32 2 1
P32 1 2
P - - c P 3 1 c P-3 1 c
P - c - P 3 c 1 P-3 c 1
R - - - R3 R-3 R32 R3m R-3m
R - - c R3c R-3c
Hexagonal
P - - - P6 P-6 P6/m P 6 2 2 P 6 m m P-6 2 m P6/mmm
P-6 m 2
P 63 - - P63 P63/m P63 2 2
P 62 - - P62 P62 2 2
P64 P64 2 2
P 61 - - P61 P61 2 2
P65 P65 2 2
P - - c P 63 m c P-6 2 c P63/mmc
P - c - P 63 c m P-6 c 2 P63/mcm
P - c c P 6 c c P6/mcc
Cubic
P - - - P23 Pm-3 P4 3 2 P-4 3 m P m -3 m
P 21(42) - - P21 3 P42 3 2
P 41 - - P41 3 2
P43 3 2
P - - n P-4 3 n P m -3 n
P a - - Pa-3
P n - - Pn-3 P n -3 m
P n - n P n -3 n
I - - - I23 Im-3 I4 3 2 I-4 3 2 I m -3 m
I21 3
I 41 - - I41 3 2
I - - d I-4 3 d
I a - - Ia-3
I a - d I a -3 d
F - - - F23 Fm-3 F4 3 2 F-4 3 m F m -3 m
F 41 - - F41 3 2
F - - c F-4 3 c F m -3 c
F d - - Fd-3 F d -3 m
F d - c F d -3 c