Disodium zinc bis-(sulfate) tetra-hydrate (zinc astrakanite) revisited.

We present a new low-temperature refinement of disodium zinc bis-(sulfate) tetra-hydrate {systematic name: poly[tetra-μ-aqua-di-μ-sulfato-zinc(II)disodium(I)]}, [Na(2)Zn(SO(4))(2)(H(2)O)(4)](n) or Zn astrakanite, which is an upgrade of previously reported data [Bukin & Nozik (1974 ▶). Zh. Strukt. Khim.15, 712-716]. The compound is part of an isostructural family containing the Mg (the original astrakanite mineral), Co and Ni species. The very regular ZnO(aqua)(4)O(sulfate)(2) octa-hedra lie on centres of symmetry, while the rather distorted NaO(aqua)(2)O(sulfate)(4) octa-hedra appear at general positions, linked into a three-dimensional network by the bridging water mol-ecules and the fully coordinated sulfate groups.

Related literature

For related literature, see: Rumanova (1958 ▶); Giglio (1958 ▶); Bukin & Nozik (1974 ▶, 1975 ▶); Díaz de Vivar et al. (2006 ▶).

Experimental

Crystal data

[Na2Zn(SO4)2(H2O)4]

M = 375.53

Monoclinic,

a = 5.5075 (2) Å

b = 8.2127 (3) Å

c = 11.0559 (4) Å

β = 99.958 (10)°

V = 492.54 (3) Å3

Z = 2

Mo Kα radiation

μ = 3.07 mm−1

T = 170 (2) K

0.30 × 0.20 × 0.10 mm

Data collection

Bruker SMART CCD diffractometer

Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ▶) T min = 0.452, T max = 0.728

3533 measured reflections

1080 independent reflections

1062 reflections with I > 2σ(I)

R int = 0.012

Refinement

R[F 2 > 2σ(F 2)] = 0.017

wR(F 2) = 0.054

S = 1.00

1080 reflections

96 parameters

6 restraints

H atoms treated by a mixture of independent and constrained refinement

Δρmax = 0.29 e Å−3

Δρmin = −0.53 e Å−3

Data collection: SMART (Bruker, 2001 ▶); cell refinement: SAINT (Bruker, 2001 ▶); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: SHELXTL (Sheldrick, 2008 ▶); software used to prepare material for publication: SHELXTL and PLATON (Spek, 2003 ▶).

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536808009719/fi2061sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536808009719/fi2061Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

[Na2Zn(SO4)2(H2O)4]	F000 = 376
Mr = 375.53	Dx = 2.539 Mg m−3
Monoclinic, P21/c	Mo Kα radiation λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 3942 reflections
a = 5.5075 (2) Å	θ = 3.8–26.7º
b = 8.2127 (3) Å	µ = 3.07 mm−1
c = 11.0559 (4) Å	T = 170 (2) K
β = 99.9580 (10)º	Prism, colourless
V = 492.54 (3) Å3	0.30 × 0.20 × 0.10 mm
Z = 2

Bruker SMART CCD diffractometer	1080 independent reflections
Radiation source: fine-focus sealed tube	1062 reflections with I > 2σ(I)
Monochromator: graphite	Rint = 0.012
T = 170(2) K	θmax = 27.9º
φ and ω scans	θmin = 3.1º
Absorption correction: multi-scan(SADABS; Sheldrick, 1996)	h = −6→7
Tmin = 0.452, Tmax = 0.728	k = −10→10
3533 measured reflections	l = −13→14

Refinement on F2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.017	H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.054	w = 1/[σ2(Fo2) + (0.0408P)2 + 0.265P] where P = (Fo2 + 2Fc2)/3
S = 1.00	(Δ/σ)max < 0.001
1080 reflections	Δρmax = 0.29 e Å−3
96 parameters	Δρmin = −0.53 e Å−3
6 restraints	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.080 (4)

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes.

	x	y	z	Uiso*/Ueq
Zn1	0.0000	0.0000	0.0000	0.00887 (13)
Na1	0.12607 (11)	0.07173 (8)	0.36217 (5)	0.01231 (17)
S1	0.37405 (6)	0.28842 (4)	0.13609 (3)	0.00821 (14)
O1	0.3516 (2)	0.27120 (14)	0.26765 (10)	0.0127 (2)
O2	0.2085 (2)	0.41630 (14)	0.07871 (10)	0.0136 (3)
O3	0.3186 (2)	0.13129 (14)	0.07174 (10)	0.0134 (2)
O4	0.63500 (19)	0.32955 (13)	0.13056 (10)	0.0127 (2)
O1W	−0.1247 (2)	0.03807 (16)	0.16331 (10)	0.0110 (2)
O2W	0.1753 (2)	−0.21442 (13)	0.08065 (10)	0.0115 (2)
H1WA	−0.215 (5)	−0.032 (3)	0.179 (2)	0.028 (7)*
H1WB	−0.207 (4)	0.123 (2)	0.156 (2)	0.023 (6)*
H2WA	0.299 (4)	−0.203 (3)	0.1341 (18)	0.021 (6)*
H2WB	0.213 (5)	−0.278 (3)	0.032 (2)	0.034 (7)*

	U11	U22	U33	U12	U13	U23
Zn1	0.01021 (18)	0.00753 (17)	0.00909 (17)	−0.00024 (7)	0.00231 (11)	−0.00054 (7)
Na1	0.0133 (3)	0.0116 (3)	0.0118 (3)	−0.0002 (2)	0.0015 (2)	0.0005 (2)
S1	0.0083 (2)	0.0075 (2)	0.0089 (2)	0.00016 (12)	0.00150 (13)	−0.00049 (12)
O1	0.0156 (6)	0.0130 (5)	0.0101 (5)	0.0014 (4)	0.0034 (4)	0.0013 (4)
O2	0.0149 (5)	0.0139 (6)	0.0119 (5)	0.0051 (4)	0.0017 (4)	0.0017 (4)
O3	0.0111 (5)	0.0109 (5)	0.0179 (5)	−0.0016 (4)	0.0022 (4)	−0.0054 (4)
O4	0.0103 (5)	0.0110 (5)	0.0176 (5)	−0.0021 (4)	0.0042 (4)	−0.0016 (4)
O1W	0.0114 (5)	0.0098 (5)	0.0122 (5)	0.0000 (4)	0.0035 (4)	0.0002 (4)
O2W	0.0120 (5)	0.0100 (5)	0.0118 (5)	0.0007 (4)	−0.0002 (4)	−0.0017 (4)

Zn1—O1Wi	2.0636 (11)	Na1—O2Wv	2.5694 (13)
Zn1—O1W	2.0636 (11)	Na1—Na1vi	3.7507 (12)
Zn1—O3	2.0952 (11)	S1—O2	1.4619 (11)
Zn1—O3i	2.0952 (11)	S1—O3	1.4797 (11)
Zn1—O2W	2.1285 (11)	S1—O1	1.4876 (11)
Zn1—O2Wi	2.1285 (11)	S1—O4	1.4878 (11)
Na1—O2ii	2.3603 (12)	O1W—H1WA	0.800 (17)
Na1—O4iii	2.3786 (12)	O1W—H1WB	0.832 (16)
Na1—O1	2.4016 (12)	O2W—H2WA	0.826 (16)
Na1—O1W	2.4017 (12)	O2W—H2WB	0.805 (16)
Na1—O2iv	2.4224 (13)
O1Wi—Zn1—O1W	180.00 (9)	O1—Na1—O2Wv	92.61 (4)
O1Wi—Zn1—O3	91.46 (4)	O1W—Na1—O2Wv	90.58 (4)
O1W—Zn1—O3	88.54 (4)	O2iv—Na1—O2Wv	74.93 (4)
O1Wi—Zn1—O3i	88.54 (4)	O2—S1—O3	110.89 (7)
O1W—Zn1—O3i	91.46 (4)	O2—S1—O1	109.97 (6)
O3—Zn1—O3i	180.00 (8)	O3—S1—O1	110.00 (7)
O1Wi—Zn1—O2W	92.62 (5)	O2—S1—O4	110.71 (7)
O1W—Zn1—O2W	87.38 (5)	O3—S1—O4	107.38 (6)
O3—Zn1—O2W	88.72 (4)	O1—S1—O4	107.81 (7)
O3i—Zn1—O2W	91.28 (4)	S1—O1—Na1	128.83 (7)
O1Wi—Zn1—O2Wi	87.38 (5)	S1—O2—Na1vii	117.79 (6)
O1W—Zn1—O2Wi	92.62 (5)	S1—O2—Na1v	135.07 (7)
O3—Zn1—O2Wi	91.28 (4)	Na1vii—O2—Na1v	103.29 (4)
O3i—Zn1—O2Wi	88.72 (4)	S1—O3—Zn1	136.09 (7)
O2W—Zn1—O2Wi	180.00 (7)	S1—O4—Na1viii	136.15 (7)
O2ii—Na1—O4iii	89.56 (4)	Zn1—O1W—Na1	126.34 (5)
O2ii—Na1—O1	112.94 (4)	Zn1—O1W—H1WA	113 (2)
O4iii—Na1—O1	105.09 (4)	Na1—O1W—H1WA	99.6 (19)
O2ii—Na1—O1W	155.87 (5)	Zn1—O1W—H1WB	107.7 (17)
O4iii—Na1—O1W	99.32 (5)	Na1—O1W—H1WB	102.0 (17)
O1—Na1—O1W	86.50 (4)	H1WA—O1W—H1WB	106 (2)
O2ii—Na1—O2iv	76.71 (4)	Zn1—O2W—Na1iv	113.77 (5)
O4iii—Na1—O2iv	89.57 (4)	Zn1—O2W—H2WA	117.7 (16)
O1—Na1—O2iv	162.11 (5)	Na1iv—O2W—H2WA	112.8 (17)
O1W—Na1—O2iv	80.94 (4)	Zn1—O2W—H2WB	114.1 (18)
O2ii—Na1—O2Wv	75.00 (4)	Na1iv—O2W—H2WB	89 (2)
O4iii—Na1—O2Wv	160.12 (5)	H2WA—O2W—H2WB	106 (2)

D—H···A	D—H	H···A	D···A	D—H···A
O1W—H1WA···O1iv	0.800 (17)	1.916 (17)	2.6977 (17)	165 (3)
O1W—H1WB···O4ix	0.832 (16)	1.901 (16)	2.7288 (17)	173 (2)
O2W—H2WA···O1iii	0.826 (16)	2.051 (18)	2.8468 (16)	162 (2)
O2W—H2WB···O4x	0.805 (16)	2.15 (2)	2.8779 (16)	151 (3)

Table 1

Selected bond lengths (Å)

Zn1—O1W	2.0636 (11)
Zn1—O3	2.0952 (11)
Zn1—O2W	2.1285 (11)
Na1—O2i	2.3603 (12)
Na1—O4ii	2.3786 (12)
Na1—O1	2.4016 (12)
Na1—O1W	2.4017 (12)
Na1—O2iii	2.4224 (13)
Na1—O2Wiv	2.5694 (13)

Symmetry codes: (i) ; (ii) ; (iii) ; (iv) .

Table 2

Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1W—H1WA⋯O1iii	0.800 (17)	1.916 (17)	2.6977 (17)	165 (3)
O1W—H1WB⋯O4v	0.832 (16)	1.901 (16)	2.7288 (17)	173 (2)
O2W—H2WA⋯O1ii	0.826 (16)	2.051 (18)	2.8468 (16)	162 (2)
O2W—H2WB⋯O4vi	0.805 (16)	2.15 (2)	2.8779 (16)	151 (3)

Symmetry codes: (ii) ; (iii) ; (v) ; (vi) .