Origin at centre (2/m)

Asymmetric unit

0 ≤ x ≤ 1; 0 ≤ y ≤ 1/2; 0 ≤ z

(1)  1

(2)  2   0, 0, z

(3)  -1   0, 0, 0

(4)  m   x, y, 0

Generators selected (1); t(1, 0, 0); t(0, 1, 0); (2); (3)

Positions

Multiplicity, Wyckoff letter, Site symmetry	Coordinates	Reflection conditions
		General:
4 j 1	(1) x, y, z (2) -x, -y, z (3) -x, -y, -z (4) x, y, -z	no conditions

		Special: no extra conditions
2 i  m	x, y, 0 -x, -y, 0
2 h  2	1/2, 1/2, z 1/2, 1/2, -z
2 g  2	1/2, 0, z 1/2, 0, -z
2 f  2	0, 1/2, z 0, 1/2, -z
2 e  2	0, 0, z 0, 0, -z
1 d  2/m	1/2, 1/2, 0
1 c  2/m	0, 1/2, 0
1 b  2/m	1/2, 0, 0
1 a  2/m	0, 0, 0

Symmetry of special projections

Along [001]   p2 a' = a   b' = b    Origin at 0, 0, z

Along [100]   2mm a' = bp    Origin at x, 0, 0

Along [010]   2mm a' = ap    Origin at 0, y, 0

Maximal non-isotypic subgroups

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I	[2] p11m (4)	1; 4
	[2] p112 (3)	1; 2
	[2] p-1 (2)	1; 3

IIa

none

IIb	[2] p112/a (a' = 2a) (7); [2] p112/b (b' = 2b) (p112/a, 7); [2] c112/b (a' = 2a, b' = 2b) (p112/a, 7)

Maximal isotypic subgroups of lowest index

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IIc	[2] p112/m (a' = 2a or b' = 2b or a' = a - b, b' = a + b) (6)

Minimal non-isotypic supergroups

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I	[2] pmmm (37); [2] pmam (40); [2] pbam (44); [2] cmmm (47); [2] p4/m (51); [3] p6/m (75)

II

none

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