Imm2 No. 44 C2v20


Axes Coordinates Wyckoff positions
2a 2b 4c 4d 8e
I Maximal translationengleiche subgroups
[2] Im11 (8) 2a 2a 4b 2 × 2a 2 × 4b
[conventional setting]I1m1
[conventional setting]C1m1 -b - c, a, c -y, x, -y + z
[2] I1m1 (8) 2a 2a 2 × 2a 4b 2 × 4b
[2] I112 (5) 2a 2b 4c 4c 2 × 4c
II Maximal klassengleiche subgroups
   Loss of centring translations
[2] Pnn2 (34) 2a 2b 4c 4c 2 × 4c
[2] Pmn21 (31) x, y + (1/4), z 2a 2a 4b 2 × 2a 2 × 4b
[2] Pnm21 (31) x + (1/4), y, z 2a 2a 2 × 2a 4b 2 × 4b
[conventional setting]Pmn21 b, a, -c y, x + (1/4), -z
[2] Pmm2 (25) 1a; 1d 1b; 1c 2e; 2f 2g; 2h 2 × 4i
   Enlarged unit cell, isomorphic
[3] Imm2 3a, b, c (1/3)x, y, z; ±((1/3), 0, 0) 2a; 4c 2b; 4c 3 × 4c 4d; 8e 3 × 8e
[p] Imm2 pa, b, c (1/p)x, y, z; +((u/p), 0, 0) 2a; ((p - 1)/2) × 4c 2b; ((p - 1)/2) × 4c p × 4c 4d; ((p - 1)/2) × 8e p × 8e
p = prime > 2; u = 1, . . ., p - 1
[3] Imm2 a, 3b, c x, (1/3)y, z; ±(0, (1/3), 0) 2a; 4d 2b; 4d 4c; 8e 3 × 4d 3 × 8e
[p] Imm2 a, pb, c x, (1/p)y, z; +(0, (u/p), 0) 2a; ((p - 1)/2) × 4d 2b; ((p - 1)/2) × 4d 4c; ((p - 1)/2) × 8e p × 4d p × 8e
p = prime > 2; u = 1, . . ., p - 1
[3] Imm2 a, b, 3c x, y, (1/3)z; ±(0, 0, (1/3)) 3 × 2a 3 × 2b 3 × 4c 3 × 4d 3 × 8e
[p] Imm2 a, b, pc x, y, (1/p)z; +(0, 0, (u/p)) p × 2a p × 2b p × 4c p × 4d p × 8e
p = prime > 2; u = 1, . . ., p - 1


Nonconventional settings
        interchange letters and sequences in Hermann-Mauguin symbols, axes and coordinates:
I2mm CA abca xyzx
Im2m CB abca xyzx










































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