Origin at -1 on 12₁a

Asymmetric unit

0 ≤ x ≤ 1; 0 ≤ y ≤ 1/4; 0 ≤ z

(1)  1	(2)  2(0, 1/2, 0)   0, y, 0	(3)  2(1/2, 0, 0)   x, 1/4, 0	(4)  2   1/4, 0, z
(5)  -1   0, 0, 0	(6)  m   x, 1/4, z	(7)  b   1/4, y, z	(8)  a   x, y, 0

Generators selected (1); t(1, 0, 0); t(0, 1, 0); (2); (3); (5)

Positions

Multiplicity, Wyckoff letter, Site symmetry	Coordinates	Reflection conditions
		General:
8 d 1	(1) x, y, z (2) -x, y + 1/2, -z (3) x + 1/2, -y + 1/2, -z (4) -x + 1/2, -y, z (5) -x, -y, -z (6) x, -y + 1/2, z (7) -x + 1/2, y + 1/2, z (8) x + 1/2, y, -z	hk: h = 2n h0: h = 2n 0k: k = 2n

		Special: as above, plus
4 c  . m .	x, 1/4, z -x, 3/4, -z x + 1/2, 1/4, -z -x + 1/2, 3/4, z	no extra conditions
4 b  . . 2	1/4, 0, z 3/4, 1/2, -z 3/4, 0, -z 1/4, 1/2, z	hk: k = 2n
4 a  -1	0, 0, 0 0, 1/2, 0 1/2, 1/2, 0 1/2, 0, 0	hk: k = 2n

Symmetry of special projections

Along [001]   p2mg a' = b   b' = -1/2a    Origin at 0, 0, z

Along [100]   2mm a' = 1/2b    Origin at x, 0, 0

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

Maximal non-isotypic subgroups

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I	[2] pb21a (33)	1; 2; 7; 8
	[2] p21ma (pm21b, 28)	1; 3; 6; 8
	[2] pbm2 (pma2, 24)	1; 4; 6; 7
	[2] p21212 (21)	1; 2; 3; 4
	[2] p21/b11 (17)	1; 3; 5; 7
	[2] p121/m1 (p21/m11, 15)	1; 2; 5; 6
	[2] p112/a (7)	1; 4; 5; 8

IIa

none

IIb

none

Maximal isotypic subgroups of lowest index

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IIc	[3] pbma (a' = 3a) (45); [3] pbma (b' = 3b) (45)

Minimal non-isotypic supergroups

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I

none

II	[2] cmme (48); [2] pmam (b' = 1/2b) (40); [2] pmma (b' = 1/2b) (41)

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