[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
      (1 | 0, 0, 0)
(2)  2   x, 0, 0
      (2x | 0, 0, 0)
(3)  c   x, 0, z
      (my | 0, 0, 1/2)
(4)  m   xy1/4
      (mz | 0, 0, 1/2)

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

Positions

Multiplicity, Wyckoff letter,
Site symmetry
Coordinates Reflection conditions

 General:
4 c 1
(1) xyz(2) x-y-z(3) x-yz + 1/2(4) xy-z + 1/2
l: l = 2n
  Special: no extra conditions
2 b  . . m 
xy1/4x-y3/4
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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