Pnc2 jpeg

International Tables for Ciystallography (2006). Vol. A, Space group 30, pp. 228-229.

Pnc2

No. 30

r⁶

^2v

Pnc 2

mm 2    Orthorhombic

Patterson symmetry Pmmm

e

♦O

⁺o

Oi+ *Q

0 ó
	o o

O ł+O

o*

o*

Origin on n 12

Asymmetric unit 0<x<f; 0<y<l; 0<z<j Symmetry operations

(1) 1    (2)2 0,0,z    (3) c x,\,z    (4) n(0,i,0 0,y,z

CONTINUED

No. 30

Pnc 2

Generators selected (1); *(1,0,0); /(0,1,0); *(0,0,1); (2); (3)

Positions

Multiplicity,    Coordinates    Reflection conditions

Wyckoff Ietter,

Site symmetry    General:

⁴ c 1 (l)x,y,z (2) x,y.z (3) x,y+\,z+ 5    (4) *,y+£,z+£    Oki : k + l=2n

hOl : 1 = 2 n OkO: k~2n 001: 1 = 2 n

Special: as above, plus

b	..2	5,0,Z	5,3,Z + 3	hkl :	k+l = 2n
a	..2	0,0, z	0,3,Z+3	hkl :	k+l = 2n

Symmetry of special projections

Along [010] p\\m a'= jc b' = a Origin at0,y,0

Along [001] p2gm    Along [100] ci ml

a' = a    b' = b    a' = b b' — c

Origin at 0,0,z    Origin at x, 0,0

Maximal non-isomorphic subgroups

I	[2] Piel (Pc, 7) 1;	3
	[2] Pnl 1 (Pc, 7) 1;	4
	[2] PI 12(P2, 3) 1;	2
Ha	nonę
Hb	[2] Pnn 2 (a' = 2a) (34)

Maximal isomorphic subgroups of lowest index

Etc [2] Pnc2 (a' = 2a) (30); [3] Pnc2 (b' = 3b) (30); [3] Pnc2 (c' = 3c) (30)

Minimal non-isomorphic supergroups

I    [2] Pban (50); [2] Pnna (52); [2] Pmna (53); [2] Pbcn(60)

D    [2] Ccc2 (37); [2] Amm2 (38); [2] Bbe2 (Aea2,41); [2] fma2 (46); [2] Pcc2 (b' = ]b) (27); [2] Pbm2 (c' = \c) {Pma2,28)

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