|
Axes |
Coordinates |
Wyckoff positions |
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|
|
2a |
2b |
6c |
| I Maximal translationengleiche subgroups |
| [2] P3 (143) |
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|
2 × 1a |
1b; 1c |
2 × 3d |
| [3] C1c1 (9) |
a, a + 2b, c |
x - (1/2)y, (1/2)y, z |
4a |
4a |
3 × 4a |
| conjugate: |
b, -2a - b, c |
-(1/2)x + y, -(1/2)x, z |
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| conjugate: |
-a - b, a - b, c |
-(1/2)(x + y), (1/2)(x - y), z |
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| II Maximal klassengleiche subgroups |
| Enlarged unit cell, non-isomorphic |
| [3] P3c1 (158) |
2a + b, -a + b, c |
(1/3)(x + y), (1/3)(-x + 2y), z; ±((2/3), (1/3), 0) |
2a; 2b; 2c |
6d |
3 × 6d |
| [3] R3c (161) |
a - b, a + 2b, 3c |
(1/3)(2x - y), (1/3)(x + y), (1/3)z; ±(0, 0, (1/3)) |
3 × 6a |
18b |
3 × 18b |
|
(hexagonal axes) |
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| [3] R3c (161) |
2a + b, -a + b, 3c |
(1/3)(x + y), (1/3)(-x + 2y), (1/3)z; ±(0, 0, (1/3)) |
3 × 6a |
18b |
3 × 18b |
|
(hexagonal axes) |
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| Enlarged unit cell, isomorphic |
| [3] P31c |
a, b, 3c |
x, y, (1/3)z; ±(0, 0, (1/3)) |
3 × 2a |
3 × 2b |
3 × 6c |
| [p] P31c |
a, b, pc |
x, y, (1/p)z; +(0, 0, (u/p)) |
p × 2a |
p × 2b |
p × 6c |
|
p = prime > 2; u = 1, . . ., p - 1 |
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| [4] P31c |
2a, 2b, c |
(1/2)x, (1/2)y, z; +((1/2), 0, 0); +(0, (1/2), 0); +((1/2), (1/2), 0) |
2a; 6c |
2b; 6c |
4 × 6c |
| [p2] P31c |
pa, pb, c |
(1/p)x, (1/p)y, z; +((u/p), (v/p), 0) |
2a; ((p2 - 1)/3) × 6c |
2b; ((p2 - 1)/3) × 6c |
p2 × 6c |
|
p = prime ≠ 3; u, v = 1, . . ., p - 1 |
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