P2/c C2h4 2/m Monoclinic No. 13 P12/c1 Patterson symmetry P12/m1 UNIQUE AXIS b, CELL CHOICE 1

Origin at -1 on glide plane c

 Asymmetric unit 0 ≤ x ≤ 1/2; 0 ≤ y ≤ 1; 0 ≤ z ≤ 1/2

Symmetry operations

 (1)  1 (2)  2   0, y, 1/4 (3)  -1   0, 0, 0 (4)  c   x, 0, z

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

Positions

Multiplicity, Wyckoff letter,
Site symmetry
Coordinates Reflection conditions
General:
 4 g 1
 (1) x, y, z (2) -x, y, -z + 1/2 (3) -x, -y, -z (4) x, -y, z + 1/2
h0l: l = 2n
00l: l = 2n
Special: as above, plus
 2 f 2
 1/2, y, 1/4 1/2, -y, 3/4
no extra conditions
 2 e 2
 0, y, 1/4 0, -y, 3/4
no extra conditions
 2 d -1
 1/2, 0, 0 1/2, 0, 1/2
hkl: l  =  2n
 2 c -1
 0, 1/2, 0 0, 1/2, 1/2
hkl: l  =  2n
 2 b -1
 1/2, 1/2, 0 1/2, 1/2, 1/2
hkl: l  =  2n
 2 a -1
 0, 0, 0 0, 0, 1/2
hkl: l  =  2n

Symmetry of special projections

 Along [001]   p2mma' = ap   b' = b   Origin at 0, 0, z Along [100]   p2gma' = b   b' = cp   Origin at x, 0, 0 Along [010]   p2a' = 1/2c   b' = a   Origin at 0, y, 0

UNIQUE AXIS b, DIFFERENT CELL CHOICES

P12/c1

UNIQUE AXIS b, CELL CHOICE 1

Origin at -1 on glide plane c

 Asymmetric unit 0 ≤ x ≤ 1/2; 0 ≤ y ≤ 1; 0 ≤ z ≤ 1/2

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

Positions

Multiplicity, Wyckoff letter,
Site symmetry
Coordinates Reflection conditions
General:
 4 g 1
 (1) x, y, z (2) -x, y, -z + 1/2 (3) -x, -y, -z (4) x, -y, z + 1/2
h0l: l = 2n
00l: l = 2n
Special: as above, plus
 2 f 2
 1/2, y, 1/4 1/2, -y, 3/4
no extra conditions
 2 e 2
 0, y, 1/4 0, -y, 3/4
no extra conditions
 2 d -1
 1/2, 0, 0 1/2, 0, 1/2
hkl: l = 2n
 2 c -1
 0, 1/2, 0 0, 1/2, 1/2
 2 b -1
 1/2, 1/2, 0 1/2, 1/2, 1/2
hkl: l = 2n
 2 a -1
 0, 0, 0 0, 0, 1/2

P12/n1

UNIQUE AXIS b, CELL CHOICE 2

Origin at -1 on glide plane n

 Asymmetric unit 0 ≤ x ≤ 1; 0 ≤ y ≤ 1; 0 ≤ z ≤ 1/4

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

Positions

Multiplicity, Wyckoff letter,
Site symmetry
Coordinates Reflection conditions
General:
 4 g 1
 (1) x, y, z (2) -x + 1/2, y, -z + 1/2 (3) -x, -y, -z (4) x + 1/2, -y, z + 1/2
h0l: h + l = 2n
h00: h = 2n
00l: l = 2n
Special: as above, plus
 2 f 2
 3/4, y, 1/4 1/4, -y, 3/4
no extra conditions
 2 e 2
 3/4, y, 3/4 1/4, -y, 1/4
no extra conditions
 2 d -1
 0, 0, 1/2 1/2, 0, 0
hkl: h + l = 2n
 2 c -1
 0, 1/2, 0 1/2, 1/2, 1/2
 2 b -1
 0, 1/2, 1/2 1/2, 1/2, 0
hkl: h + l = 2n
 2 a -1
 0, 0, 0 1/2, 0, 1/2

P12/a1

UNIQUE AXIS b, CELL CHOICE 3

Origin at -1 on glide plane a

 Asymmetric unit 0 ≤ x ≤ 1/2; 0 ≤ y ≤ 1; 0 ≤ z ≤ 1/2

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

Positions

Multiplicity, Wyckoff letter,
Site symmetry
Coordinates Reflection conditions
General:
 4 g 1
 (1) x, y, z (2) -x + 1/2, y, -z (3) -x, -y, -z (4) x + 1/2, -y, z
h0l: h = 2n
h00: h = 2n
Special: as above, plus
 2 f 2
 3/4, y, 1/2 1/4, -y, 1/2
no extra conditions
 2 e 2
 1/4, y, 0 3/4, -y, 0
no extra conditions
 2 d -1
 1/2, 0, 1/2 0, 0, 1/2
hkl: h = 2n
 2 c -1
 0, 1/2, 0 1/2, 1/2, 0
 2 b -1
 1/2, 1/2, 1/2 0, 1/2, 1/2
hkl: h = 2n
 2 a -1
 0, 0, 0 1/2, 0, 0

 P2/c C2h4 2/m Monoclinic No. 13 P112/a Patterson symmetry P112/m UNIQUE AXIS c, CELL CHOICE 1

Origin at -1 on glide plane a

 Asymmetric unit 0 ≤ x ≤ 1/2; 0 ≤ y ≤ 1/2; 0 ≤ z ≤ 1

Symmetry operations

 (1)  1 (2)  2   1/4, 0, z (3)  -1   0, 0, 0 (4)  a   x, y, 0

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

Positions

Multiplicity, Wyckoff letter,
Site symmetry
Coordinates Reflection conditions
General:
 4 g 1
 (1) x, y, z (2) -x + 1/2, -y, z (3) -x, -y, -z (4) x + 1/2, y, -z
hk0: h = 2n
h00: h = 2n
Special: as above, plus
 2 f 2
 1/4, 1/2, z 3/4, 1/2, -z
no extra conditions
 2 e 2
 1/4, 0, z 3/4, 0, -z
no extra conditions
 2 d -1
 0, 1/2, 0 1/2, 1/2, 0
hkl: h  =  2n
 2 c -1
 0, 0, 1/2 1/2, 0, 1/2
hkl: h  =  2n
 2 b -1
 0, 1/2, 1/2 1/2, 1/2, 1/2
hkl: h  =  2n
 2 a -1
 0, 0, 0 1/2, 0, 0
hkl: h  =  2n

Symmetry of special projections

 Along [001]   p2a' = 1/2a   b' = b   Origin at 0, 0, z Along [100]   p2mma' = bp   b' = c   Origin at x, 0, 0 Along [010]   p2gma' = c   b' = ap   Origin at 0, y, 0

UNIQUE AXIS c, DIFFERENT CELL CHOICES

P112/a

UNIQUE AXIS c, CELL CHOICE 1

Origin at -1 on glide plane a

 Asymmetric unit 0 ≤ x ≤ 1/2; 0 ≤ y ≤ 1/2; 0 ≤ z ≤ 1

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

Positions

Multiplicity, Wyckoff letter,
Site symmetry
Coordinates Reflection conditions
General:
 4 g 1
 (1) x, y, z (2) -x + 1/2, -y, z (3) -x, -y, -z (4) x + 1/2, y, -z
hk0: h = 2n
h00: h = 2n
Special: as above, plus
 2 f 2
 1/4, 1/2, z 3/4, 1/2, -z
no extra conditions
 2 e 2
 1/4, 0, z 3/4, 0, -z
no extra conditions
 2 d -1
 0, 1/2, 0 1/2, 1/2, 0
hkl: h = 2n
 2 c -1
 0, 0, 1/2 1/2, 0, 1/2
 2 b -1
 0, 1/2, 1/2 1/2, 1/2, 1/2
hkl: h = 2n
 2 a -1
 0, 0, 0 1/2, 0, 0

P112/n

UNIQUE AXIS c, CELL CHOICE 2

Origin at -1 on glide plane n

 Asymmetric unit 0 ≤ x ≤ 1/4; 0 ≤ y ≤ 1; 0 ≤ z ≤ 1

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

Positions

Multiplicity, Wyckoff letter,
Site symmetry
Coordinates Reflection conditions
General:
 4 g 1
 (1) x, y, z (2) -x + 1/2, -y + 1/2, z (3) -x, -y, -z (4) x + 1/2, y + 1/2, -z
hk0: h + k = 2n
h00: h = 2n
0k0: k = 2n
Special: as above, plus
 2 f 2
 1/4, 3/4, z 3/4, 1/4, -z
no extra conditions
 2 e 2
 3/4, 3/4, z 1/4, 1/4, -z
no extra conditions
 2 d -1
 1/2, 0, 0 0, 1/2, 0
hkl: h + k = 2n
 2 c -1
 0, 0, 1/2 1/2, 1/2, 1/2
 2 b -1
 1/2, 0, 1/2 0, 1/2, 1/2
hkl: h + k = 2n
 2 a -1
 0, 0, 0 1/2, 1/2, 0

P112/b

UNIQUE AXIS c, CELL CHOICE 3

Origin at -1 on glide plane b

 Asymmetric unit 0 ≤ x ≤ 1/2; 0 ≤ y ≤ 1/2; 0 ≤ z ≤ 1

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

Positions

Multiplicity, Wyckoff letter,
Site symmetry
Coordinates Reflection conditions
General:
 4 g 1
 (1) x, y, z (2) -x, -y + 1/2, z (3) -x, -y, -z (4) x, y + 1/2, -z
hk0: k = 2n
0k0: k = 2n
Special: as above, plus
 2 f 2
 1/2, 3/4, z 1/2, 1/4, -z
no extra conditions
 2 e 2
 0, 1/4, z 0, 3/4, -z
no extra conditions
 2 d -1
 1/2, 1/2, 0 1/2, 0, 0
hkl: k = 2n
 2 c -1
 0, 0, 1/2 0, 1/2, 1/2
 2 b -1
 1/2, 1/2, 1/2 1/2, 0, 1/2
hkl: k = 2n
 2 a -1
 0, 0, 0 0, 1/2, 0