Cmmm | No. 65 | C2/m2/m2/m | D2h19 |
Axes | Coordinates | Wyckoff positions | ||||||||||||
2a | 2b | 2c | 2d | 4e | 4f | 4g | 4h | 4i | 4j | 4k | 4l | |||
8m | 8n | 8o | 8p | 8q | 16r | |||||||||
I Maximal translationengleiche subgroups | ||||||||||||||
[2] C2mm (38) | 2a | 2a | 2b | 2b | 4d | 4e | 2 × 2a | 2 × 2b | 4d | 4e | 4c | 4c | ||
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c, -b, a | z, -y, x | 8f | 8f | 2 × 4c | 2 × 4d | 2 × 4e | 2 × 8f | ||||||
[2] Cm2m (38) | 2a | 2a | 2b | 2b | 4d | 4e | 4d | 4e | 2 × 2a | 2 × 2b | 4c | 4c | ||
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c, a, b | z, x, y | 8f | 2 × 4c | 8f | 2 × 4d | 2 × 4e | 2 × 8f | ||||||
[2] Cmm2 (35) | 2a | 2b | 2b | 2a | 4c | 4c | 4d | 4d | 4e | 4e | 2 × 2a | 2 × 2b | ||
2 × 4c | 2 × 4e | 2 × 4d | 8f | 8f | 2 × 8f | |||||||||
[2] C222 (21) | 2a | 2b | 2c | 2d | 4k | 4k | 4e | 4f | 4g | 4h | 4i | 4j | ||
2 × 4k | 8l | 8l | 8l | 8l | 2 × 8l | |||||||||
[2] C2/m11(12) | 2a | 2b | 2d | 2c | 4e | 4f | 4g | 4h | 4i | 4i | 4i | 4i | ||
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b, -a, c | y, -x, z | 8j | 2 × 4i | 8j | 8j | 8j | 2 × 8j | ||||||
[2] C12/m1(12) | 2a | 2b | 2d | 2c | 4e | 4f | 4i | 4i | 4g | 4h | 4i | 4i | ||
8j | 8j | 2 × 4i | 8j | 8j | 2 × 8j | |||||||||
[2] P112/m(10) | a, (1/2)(-a + b), c | x + y, 2y, z | 1a | 1c | 1f | 1b | 1d; 1g | 1e; 1h | 2m | 2n | 2m | 2n | 2i | 2k |
2j; 2l | 4o | 4o | 2 × 2m | 2 × 2n | 2 × 4o | |||||||||
or: | (1/2)(a - b), | x - y, x + y, z | 1a | 1g | 1h | 1b | 1c; 1d | 1e; 1f | 2m | 2n | 2m | 2n | 2i | 2l |
(1/2)(a + b), c | 2j; 2k | 4o | 4o | 2 × 2m | 2 × 2n | 2 × 4o | ||||||||
II Maximal klassengleiche subgroups | ||||||||||||||
Loss of centring translations | ||||||||||||||
[2] Pmmn (59) | origin 1: x, y, z | 2a | 2b | 2b | 2a | 4c | 4d | 4f | 4f | 4e | 4e | 2 × 2a | 2 × 2b | |
origin 2: x + (1/4), y + (1/4), z | 8g | 2 × 4e | 2 × 4f | 8g | 8g | 2 × 8g | ||||||||
[2] Pbam (55) | 2a | 2c | 2d | 2b | 4g | 4h | 4g | 4h | 4g | 4h | 4e | 4f | ||
8i | 8i | 8i | 2 × 4g | 2 × 4h | 2 × 8i | |||||||||
[2] Pbmn (53) | 2a | 2b | 2c | 2d | 4g | 4g | 4h | 4h | 4e | 4f | 4h | 4h | ||
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b, c, a | y, z, x | 2 × 4g | 8i | 2 × 4h | 8i | 8i | 2 × 8i | ||||||
[2] Pman (53) | 2a | 2b | 2c | 2d | 4g | 4g | 4e | 4f | 4h | 4h | 4h | 4h | ||
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a, -c, b | x, -z, y | 2 × 4g | 2 × 4h | 8i | 8i | 8i | 2 × 8i | ||||||
[2] Pbmm (51) | x + (1/4), y + (1/4), z | 2e | 2e | 2f | 2f | 2a; 2c | 2b; 2d | 2 × 2e | 2 × 2f | 4i | 4j | 4k | 4k | |
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b, c, a | y + (1/4), z, x + (1/4) | 4g; 4h | 8l | 2 × 4k | 2 × 4i | 2 × 4j | 2 × 8l | ||||||
[2] Pmam (51) | x + (1/4), y + (1/4), z | 2e | 2e | 2f | 2f | 2a; 2c | 2b; 2d | 4i | 4j | 2 × 2e | 2 × 2f | 4k | 4k | |
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a, -c, b | x + (1/4), -z, y + (1/4) | 4g; 4h | 2 × 4k | 8l | 2 × 4i | 2 × 4j | 2 × 8l | ||||||
[2] Pban (50) | origin 1: x, y, z | 2a | 2b | 2c | 2d | 4e | 4f | 4g | 4h | 4i | 4j | 4k | 4l | |
origin 2: x + (1/4), y + (1/4), z | 8m | 8m | 8m | 8m | 8m | 2 × 8m | ||||||||
[2] Pmmm (47) | 1a; 1f | 1b; 1e | 1d; 1g | 1c; 1h | 4y | 4z | 2i; 2k | 2j; 2l | 2m; 2o | 2n; 2p | 2q; 2t | 2r; 2s | ||
8![]() |
4u; 4v | 4w; 4x | 2 × 4y | 2 × 4z | 2 × 8![]() |
Axes | Coordinates | Wyckoff positions | ||||||||||||
2a | 2b | 2c | 2d | 4e | 4f | 4g | 4h | 4i | 4j | 4k | 4l | |||
8m | 8n | 8o | 8p | 8q | 16r | |||||||||
Enlarged unit cell, non-isomorphic | ||||||||||||||
[2] Ibmm (74) | a, b, 2c | x, y, (1/2)z; | 4a | 4b | 4e | 4e | 8g | 4c; 4d | 8h | 2 × 4e | 8f | 8i | 8h | 8h |
+(0, 0, (1/2)) | 2 × 8g | 16j | 2 × 8h | 16j | 2 × 8i | 2 × 16j | ||||||||
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b, 2c, a | y, (1/2)z, x; | ||||||||||||
+(0, (1/2), 0) | ||||||||||||||
[2] Ibmm (74) | a, b, 2c | x, y, (1/2)z + (1/4); | 4e | 4e | 4b | 4a | 4c; 4d | 8g | 2 × 4e | 8h | 8i | 8f | 8h | 8h |
+(0, 0, (1/2)) | 2 × 8g | 16j | 2 × 8h | 2 × 8i | 16j | 2 × 16j | ||||||||
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b, 2c, a | y, (1/2)z + (1/4), x; | ||||||||||||
+(0, (1/2), 0) | ||||||||||||||
[2] Imam (74) | a, b, 2c | x, y, (1/2)z; | 4a | 4b | 4e | 4e | 8g | 4c; 4d | 8f | 8i | 8h | 2 × 4e | 8h | 8h |
+(0, 0, (1/2)) | 2 × 8g | 2 × 8h | 16j | 16j | 2 × 8i | 2 × 16j | ||||||||
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a, -2c, b | x, -(1/2)z, y; | ||||||||||||
+(0, (1/2), 0) | ||||||||||||||
[2] Imam (74) | a, b, 2c | x, y, (1/2)z + (1/4); | 4e | 4e | 4b | 4a | 4c; 4d | 8g | 8i | 8f | 2 × 4e | 8h | 8h | 8h |
+(0, 0, (1/2)) | 2 × 8g | 2 × 8h | 16j | 2 × 8i | 16j | 2 × 16j | ||||||||
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a, -2c, b | x, -(1/2)z - (1/4), y; | ||||||||||||
+(0, 0, (1/2)) | ||||||||||||||
[2] Ibam (72) | a, b, 2c | x, y, (1/2)z; | 4c | 4d | 4b | 4a | 8j | 8e | 8j | 8f | 8j | 8g | 8h | 8i |
+(0, 0, (1/2)) | 16k | 16k | 16k | 2 × 8j | 16k | 2 × 16k | ||||||||
[2] Ibam (72) | a, b, 2c | x, y, (1/2)z + (1/4); | 4a | 4b | 4d | 4c | 8e | 8j | 8f | 8j | 8g | 8j | 8h | 8i |
+(0, 0, (1/2)) | 16k | 16k | 16k | 16k | 2 × 8j | 2 × 16k | ||||||||
[2] Immm(71) | a, b, 2c | x, y, (1/2)z; | 2a; 2c | 2b; 2d | 4j | 4i | 8n | 8k | 4e; 4f | 8m | 4g; 4h | 8l | 2 × 4i | 2 × 4j |
+(0, 0, (1/2)) | 16o | 2 × 8l | 2 × 8m | 2 × 8n | 16o | 2 × 16o | ||||||||
[2] Immm(71) | a, b, 2c | x, y, (1/2)z + (1/4); | 4i | 4j | 2b; 2d | 2a; 2c | 8k | 8n | 8m | 4e; 4f | 8l | 4g; 4h | 2 × 4i | 2 × 4j |
+(0, 0, (1/2)) | 16o | 2 × 8l | 2 × 8m | 16o | 2 × 8n | 2 × 16o | ||||||||
[2] Cccm (66) | a, b, 2c | x, y, (1/2)z; | 4c | 4d | 4b | 4a | 4e; 4f | 8k | 8l | 8g | 8l | 8h | 8i | 8j |
+(0, 0, (1/2)) | 2 × 8k | 16m | 16m | 2 × 8l | 16m | 2 × 16m | ||||||||
[2] Cccm (66) | a, b, 2c | x, y, (1/2)z + (1/4); | 4a | 4b | 4d | 4c | 8k | 4e; 4f | 8g | 8l | 8h | 8l | 8i | 8j |
+(0, 0, (1/2)) | 2 × 8k | 16m | 16m | 16m | 2 × 8l | 2 × 16m | ||||||||
[2] Ccmm (63) | a, b, 2c | x, y, (1/2)z; | 4a | 4b | 4c | 4c | 8d | 8g | 8f | 2 × 4c | 8e | 8g | 8f | 8f |
+(0, 0, (1/2)) | 16h | 16h | 2 × 8f | 16h | 2 × 8g | 2 × 16h | ||||||||
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b, -a, 2c | y, -x, (1/2)z; | ||||||||||||
+(0, 0, (1/2)) | ||||||||||||||
[2] Ccmm (63) | a, b, 2c | x, y, (1/2)z + (1/4); | 4c | 4c | 4b | 4a | 8g | 8d | 2 × 4c | 8f | 8g | 8e | 8f | 8f |
+(0, 0, (1/2)) | 16h | 16h | 2 × 8f | 2 × 8g | 16h | 2 × 16h | ||||||||
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b, -a, 2c | y, -x, (1/2)z + (1/4); | ||||||||||||
+(0, 0, (1/2)) | ||||||||||||||
[2] Cmcm (63) | a, b, 2c | x, y, (1/2)z; | 4a | 4b | 4c | 4c | 8d | 8g | 8e | 8g | 8f | 2 × 4c | 8f | 8f |
+(0, 0, (1/2)) | 16h | 2 × 8f | 16h | 16h | 2 × 8g | 2 × 16h | ||||||||
[2] Cmcm (63) | a, b, 2c | x, y, (1/2)z + (1/4); | 4c | 4c | 4b | 4a | 8g | 8d | 8g | 8e | 2 × 4c | 8f | 8f | 8f |
+(0, 0, (1/2)) | 16h | 2 × 8f | 16h | 2 × 8g | 16h | 2 × 16h |
Axes | Coordinates | Wyckoff positions | ||||||||||
2a | 2b | 2c | 2d | 4e | 4f | 4g | 4h | 4i | 4j | |||
4k | 4l | 8m | 8n | 8o | 8p | 8q | 16r | |||||
Enlarged unit cell, isomorphic | ||||||||||||
[3] Cmmm | 3a, b, c | (1/3)x, y, z; | 2a; 4g | 2b; 4g | 2c; 4h | 2d; 4h | 4e; 8p | 4f; 8q | 3 × 4g | 3 × 4h | 4i; 8p | 4j; 8q |
±((1/3), 0, 0) | 4k; 8o | 4l; 8o | 8m; 16r | 8n; 16r | 3 × 8o | 3 × 8p | 3 × 8q | 3 × 16r | ||||
[p] Cmmm | pa, b, c | (1/p)x, y, z; | 2a; | 2b; | 2c; | 2d; | 4e; | 4f; | p × 4g | p × 4h | 4i; | 4j; |
+((u/p), 0, 0) | ((p - 1)/2) × 4g | ((p - 1)/2) × 4g | ((p - 1)/2) × 4h | ((p - 1)/2) × 4h | ((p - 1)/2) × 8p | ((p - 1)/2) × 8q | ((p - 1)/2) × 8p | ((p - 1)/2) × 8q | ||||
p = prime > 2; | 4k; | 4l; | 8m; | 8n; | p × 8o | p × 8p | p × 8q | p × 16r | ||||
u = 1, . . ., p - 1 | ((p - 1)/2) × 8o | ((p - 1)/2) × 8o | ((p - 1)/2) × 16r | ((p - 1)/2) × 16r | ||||||||
[3] Cmmm | a, 3b, c | x, (1/3)y, z; | 2a; 4i | 2b; 4i | 2c; 4j | 2d; 4j | 4e; 8p | 4f; 8q | 4g; 8p | 4h; 8q | 3 × 4i | 3 × 4j |
±(0, (1/3), 0) | 4k; 8n | 4l; 8n | 8m; 16r | 3 × 8n | 8o; 16r | 3 × 8p | 3 × 8q | 3 × 16r | ||||
[p] Cmmm | a, pb, c | x, (1/p)y, z; | 2a; | 2b; | 2c; | 2d; | 4e; | 4f; | 4g; | 4h; | p × 4i | p × 4j |
+(0, (u/p), 0) | ((p - 1)/2) × 4i | ((p - 1)/2) × 4i | ((p - 1)/2) × 4j | ((p - 1)/2) × 4j | ((p - 1)/2) × 8p | ((p - 1)/2) × 8q | ((p - 1)/2) × 8p | ((p - 1)/2) × 8q | ||||
p = prime > 2; | 4k; | 4l; | 8m; | p × 8n | 8o; | p × 8p | p × 8q | p × 16r | ||||
u = 1, . . ., p - 1 | ((p - 1)/2) × 8n | ((p - 1)/2) × 8n | ((p - 1)/2) × 16r | ((p - 1)/2) × 16r | ||||||||
[2] Cmmm | a, b, 2c | x, y, (1/2)z; | 2a; 2d | 2b; 2c | 4l | 4k | 4e; 4f | 8m | 4g; 4h | 8o | 4i; 4j | 8n |
+(0, 0, (1/2)) | 2 × 4k | 2 × 4l | 2 × 8m | 2 × 8n | 2 × 8o | 8p; 8q | 16r | 2 × 16r | ||||
[2] Cmmm | a, b, 2c | x, y, (1/2)z + (1/4); | 4k | 4l | 2b; 2c | 2a; 2d | 8m | 4e; 4f | 8o | 4g; 4h | 8n | 4i; 4j |
+(0, 0, (1/2)) | 2 × 4k | 2 × 4l | 2 × 8m | 2 × 8n | 2 × 8o | 16r | 8p; 8q | 2 × 16r | ||||
[3] Cmmm | a, b, 3c | x, y, (1/3)z; | 2a; 4k | 2b; 4l | 2c; 4l | 2d; 4k | 4e; 8m | 4f; 8m | 4g; 8o | 4h; 8o | 4i; 8n | 4j; 8n |
±(0, 0, (1/3)) | 3 × 4k | 3 × 4l | 3 × 8m | 3 × 8n | 3 × 8o | 8p; 16r | 8q; 16r | 3 × 16r | ||||
[p] Cmmm | a, b, pc | x, y, (1/p)z; | 2a; | 2b; | 2c; | 2d; | 4e; | 4f; | 4g; | 4h; | 4i; | 4j; |
+(0, 0, (u/p)) | ((p - 1)/2) × 4k | ((p - 1)/2) × 4l | ((p - 1)/2) × 4l | ((p - 1)/2) × 4k | ((p - 1)/2) × 8m | ((p - 1)/2) × 8m | ((p - 1)/2) × 8o | ((p - 1)/2) × 8o | ((p - 1)/2) × 8n | ((p - 1)/2) × 8n | ||
p = prime > 2; | p × 4k | p × 4l | p × 8m | p × 8n | p × 8o | 8p; | 8q; | p × 16r | ||||
u = 1, . . ., p - 1 | ((p - 1)/2) × 16r | ((p - 1)/2) × 16r |
Nonconventional settings interchange letters and sequences in Hermann-Mauguin symbols, axes and coordinates: |
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Ammm | C → A→ B | a→ b → c → a | a→ b → c → a | x→ y → z → x |
Bmmm | A→ C→ B | a← b ← c ← a | a← b ← c ← a | x← y ← z ← x |