Pba2 C2v8 mm2 Orthorhombic No. 32 Pba2 Patterson symmetry Pmmm

Origin on 1 1 2

 Asymmetric unit 0 ≤ x ≤ 1/2; 0 ≤ y ≤ 1/2; 0 ≤ z ≤ 1

Symmetry operations

 (1)  1 (2)  2   0, 0, z (3)  a   x, 1/4, z (4)  b   1/4, y, z

Generators selected (1); t(1, 0, 0); t(0, 1, 0); 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 + 1/2, -y + 1/2, z (4) -x + 1/2, y + 1/2, z
0kl : k = 2n
h0l : h = 2n
h00 : h = 2n
0k0 : k = 2n
Special: as above, plus
 2 b . . 2
 0, 1/2, z 1/2, 0, z
hkl : h + k = 2n
 2 a . . 2
 0, 0, z 1/2, 1/2, z
hkl : h + k = 2n

Symmetry of special projections

 Along [001]   p2gga' = a   b' = b   Origin at 0, 0, z Along [100]   p1m1a' = 1/2b   b' = c   Origin at x, 0, 0 Along [010]   p11ma' = c   b' = 1/2a   Origin at 0, y, 0

Maximal non-isomorphic subgroups

 I [2] P1a1 (Pc, 7) 1; 3 [2] Pb11 (Pc, 7) 1; 4 [2] P112 (P2, 3) 1; 2
 IIa none
 IIb [2] Pnn2 (c' = 2c) (34); [2] Pna21 (c' = 2c) (33); [2] Pbn21 (c' = 2c) (Pna21, 33)

Maximal isomorphic subgroups of lowest index

 IIc [2] Pba2 (c' = 2c) (32); [3] Pba2 (a' = 3a or b' = 3b) (32)

Minimal non-isomorphic supergroups

 I [2] Pban (50); [2] Pcca (54); [2] Pbam (55); [2] P4bm (100); [2] P42bc (106); [2] P-4b2 (117)
 II [2] Cmm2 (35); [2] Aea2 (41); [2] Bbe2 (Aea2, 41); [2] Iba2 (45); [2] Pbm2 (a' = 1/2a) (Pma2, 28); [2] Pma2 (b' = 1/2b) (28)