Origin at -1 at 21 21 n, at -1/4, -1/4, 0 from m m 2
| Asymmetric unit | 0 ≤ x ≤ 1/4; -1/4 ≤ y ≤ 1/4; 0 ≤ z ≤ 1 |
| (1) 1 | (2) 2 1/4, 1/4, z | (3) 2(0, 1/2, 0) 0, y, 0 | (4) 2(1/2, 0, 0) x, 0, 0 |
| (5) -1 0, 0, 0 | (6) n(1/2, 1/2, 0) x, y, 0 | (7) m x, 1/4, z | (8) m 1/4, y, z |
Generators selected (1); t(1, 0, 0); t(0, 1, 0); t(0, 0, 1); (2); (3); (5)
Multiplicity, Wyckoff letter,
Site symmetry | Coordinates | Reflection conditions |
| | | General:
|
| | (1) x, y, z | (2) -x + 1/2, -y + 1/2, z | (3) -x, y + 1/2, -z | (4) x + 1/2, -y, -z | | (5) -x, -y, -z | (6) x + 1/2, y + 1/2, -z | (7) x, -y + 1/2, z | (8) -x + 1/2, y, z |
| hk0 : h + k = 2n
h00 : h = 2n
0k0 : k = 2n
|
| | | Special: as above, plus
|
| | x, 1/4, z | -x + 1/2, 1/4, z | -x, 3/4, -z | x + 1/2, 3/4, -z |
| no extra conditions |
| | 1/4, y, z | 1/4, -y + 1/2, z | 3/4, y + 1/2, -z | 3/4, -y, -z |
| no extra conditions |
| | 0, 0, 1/2 | 1/2, 1/2, 1/2 | 0, 1/2, 1/2 | 1/2, 0, 1/2 |
| hkl : h, k = 2n
|
| | 0, 0, 0 | 1/2, 1/2, 0 | 0, 1/2, 0 | 1/2, 0, 0 |
| hkl : h, k = 2n
|
| | no extra conditions |
| | no extra conditions |
Symmetry of special projections
Along [001] c2mm
a' = a b' = b
Origin at 1/4, 1/4, z | Along [100] p2mg
a' = b b' = c
Origin at x, 0, 0 | Along [010] p2gm
a' = c b' = a
Origin at 0, y, 0 |
Maximal non-isomorphic subgroups
| I | | [2] Pm21n (Pmn21, 31) | 1; 3; 6; 8 |
| | | [2] P21mn (Pmn21, 31) | 1; 4; 6; 7 |
| | | [2] Pmm2 (25) | 1; 2; 7; 8 |
| | | [2] P21212 (18) | 1; 2; 3; 4 |
| | | [2] P112/n (P2/c, 13) | 1; 2; 5; 6 |
| | | [2] P121/m1 (P21/m, 11) | 1; 3; 5; 7 |
| | | [2] P21/m11 (P21/m, 11) | 1; 4; 5; 8 |
| IIb | [2] Pcmn (c' = 2c) (Pnma, 62); [2] Pmcn (c' = 2c) (Pnma, 62); [2] Pccn (c' = 2c) (56) |
Maximal isomorphic subgroups of lowest index
| IIc | [2] Pmmn (c' = 2c) (59); [3] Pmmn (a' = 3a or b' = 3b) (59) |
Minimal non-isomorphic supergroups
| I | [2] P4/nmm (129); [2] P42/nmc (137) |
| II | [2] Amma (Cmcm, 63); [2] Bmmb (Cmcm, 63); [2] Cmmm (65); [2] Immm (71); [2] Pmmb (a' = 1/2a) (Pmma, 51); [2] Pmma (b' = 1/2b) (51) |
