[script p]2mm 2mm Orthorhombic
No. 18 [script p]2mm Patterson symmetry [script p]mmm

symmetry group diagram

Origin on 2mm

Asymmetric unit 0 ≤ y; 0 ≤ z ≤ 1/2

Symmetry operations

(1)  1
      (1 | 0, 0, 0)
(2)  2   x, 0, 0
      (2x | 0, 0, 0)
(3)  m   xy, 0
      (mz | 0, 0, 0)
(4)  m   x, 0, z
      (my | 0, 0, 0)

Generators selected (1); t(0, 0, 1); (2); (3)

Positions

Multiplicity, Wyckoff letter,
Site symmetry
Coordinates Reflection conditions

 General:
4 f 1
(1) xyz(2) x-y-z(3) xy-z(4) x-yz
no conditions
  Special: no extra conditions
2 e  . m . 
x, 0, zx, 0, -z
2 d  . . m 
xy1/2x-y1/2
2 c  . . m 
xy, 0x-y, 0
1 b  2 m m 
x, 0, 1/2
1 a  2 m m 
x, 0, 0

Symmetry of special projections

Along [001]   11m

Origin at 0, 0, z
Along [100]   [script p]2mm
a' = c   
Origin at x, 0, 0
Along [010]   [script p]1m1
a' = c   
Origin at 0, y, 0

Maximal non-isotypic non-enantiomorphic subgroups


I[2] [script p]11m (10)1; 3
 [2] [script p]1m1 ([script p]m11, 4)1; 4
 [2] [script p]211 (3)1; 2
IIa none
IIb[2] [script p]2cm (c' = 2c) (19)

Maximal isotypic subgroups and enantiomorphic subgroups of lowest index


IIc[2] [script p]2mm (c' = 2c) (18)

Minimal non-isotypic non-enantiomorphic supergroups


I[2] [script p]mmm (20); [2] [script p]mcm (22); [3] [script p]-6m2 (71)
IInone








































to end of page
to top of page