[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   (2)  2   x, 0, 0(3)  m   x, y, 0(4)  m   x, 0, z

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

Positions

Multiplicity, Wyckoff letter,
Site symmetry		 Coordinates Reflection conditions
 General:
4 f 1
(1) x, y, z(2) x, -y, -z(3) x, y, -z(4) x, -y, z
no conditions
  Special: no extra conditions
2 e  . m . 
x, 0, zx, 0, -z
2 d  . . m 
x, y, 1/2x, -y, 1/2
2 c  . . m 
x, y, 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








































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