[script p]2cm 2mm Orthorhombic
No. 19 [script p]2cm Patterson symmetry [script p]mmm

symmetry group diagram

Origin on 2c1

Asymmetric unit 0 ≤ z ≤ 1/4

Symmetry operations

(1)  1   (2)  2   x, 0, 0(3)  c   x, 0, z(4)  m   x, y, 1/4

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

Positions

Multiplicity, Wyckoff letter,
Site symmetry		 Coordinates Reflection conditions
 General:
4 c 1
(1) x, y, z(2) x, -y, -z(3) x, -y, z + 1/2(4) x, y, -z + 1/2
l: l = 2n
  Special: no extra conditions
2 b  . . m 
x, y, 1/4x, -y, 3/4
2 a  2 . . 
x, 0, 0x, 0, 1/2

Symmetry of special projections

Along [001]   11m

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

Maximal non-isotypic non-enantiomorphic subgroups

I[2] [script p]11m (10)1; 4
 [2] [script p]1c1 ([script p]c11, 5)1; 3
 [2] [script p]211 (3)1; 2
IIa none
IIbnone

Maximal isotypic subgroups and enantiomorphic subgroups of lowest index

IIc[3] [script p]2cm (c' = 3c) (19)

Minimal non-isotypic non-enantiomorphic supergroups

I[2] [script p]ccm (21); [2] [script p]mcm (22); [3] [script p]-6c2 (72)
II[2] [script p]2mm (c' = 1/2c) (18)








































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