Poly[di-μ₃-hydroxy­methane­sulfinato-zinc(II)]

Zinc(II) formaldehyde sulfoxylate, [Zn(CH₃O₃S)₂], a widely marketed additive in the polymer and textile industry (under the registered trademarks Decroline, Decolin and Safolin, CAS 24887-06-7), possesses, in the solid state, a polymeric framework, with the Zn atoms octa­hedrally coordinated by six O atoms of four different hydroxy­methane­sulfinate groups. The latter are found to coordinate through all their O atoms, including the hydr­oxy ones, and possess a chelating nature. By contrast, in the structure of the only other commercially available salt of this ligand (dihydrated sodium formaldehyde sulfoxylate), the organic residue, being involved in an extensive network of hydrogen-bond contacts, is fully stretched and bridges two Na^I ions through a single O atom.

Key indicators

• Single-crystal X-ray study
• T = 295 K
• Mean [sigma](O-C) = 0.010 Å
• R factor = 0.028
• wR factor = 0.074
• Data-to-parameter ratio = 6.0

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT089_ALERT_3_C Poor Data / Parameter Ratio (Zmax .LT. 18) .....       6.05
PLAT731_ALERT_1_C Bond    Calc     0.82(4), Rep   0.820(10) ......       4.00 su-Rat
              O6   -H6      1.555   1.555
PLAT764_ALERT_4_C Overcomplete CIF Bond List Detected (Rep/Expd) .       1.21 Ratio

Alert level G
REFLT03_ALERT_4_G  WARNING: Large fraction of Friedel related reflns may
                     be needed to determine absolute structure
           From the CIF: _diffrn_reflns_theta_max           25.27
           From the CIF: _reflns_number_total                653
           Count of symmetry unique reflns          653
           Completeness (_total/calc)            100.00%
           TEST3: Check Friedels for noncentro structure
           Estimate of Friedel pairs measured         0
           Fraction of Friedel pairs measured     0.000
           Are heavy atom types Z>Si present        yes

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   3 ALERT level C = Check and explain
   1 ALERT level G = General alerts; check

   1 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   0 ALERT type 2 Indicator that the structure model may be wrong or deficient
   1 ALERT type 3 Indicator that the structure quality may be low
   2 ALERT type 4 Improvement, methodology, query or suggestion


checkCIF publication errors

Alert level A
PUBL023_ALERT_1_A There is a mismatched ^ on line 189
              'Masciocchi^, Norberto'
              If you require a ^ then it should be escaped
              with a \, i.e. \^
              Otherwise there must be a matching closing ~, e.g. ^12^C

   1 ALERT level A = Data missing that is essential or data in wrong format
   0 ALERT level G = General alerts. Data that may be required is missing

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Computing details

Data collection: CAD-4 Software (Enraf–Nonius, 1989); cell refinement: CAD-4 Software; data reduction: local programs; program(s) used to solve structure: SHELXS86 (Sheldrick, 1986); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEP-3 in WinGX (Farrugia, 1999); software used to prepare material for publication: SHELXL97.

Poly[di-µ₃-hydroxymethanesulfinato-zinc(II)]

Crystal data

[Zn(CH3O3S)2]	F(000) = 512
Mr = 255.56	Dx = 2.360 Mg m^−3
Monoclinic, Cc	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: C -2yc	Cell parameters from 25 reflections
a = 8.332 (5) Å	θ = 9–12°
b = 10.797 (10) Å	µ = 3.97 mm^−1
c = 8.939 (2) Å	T = 295 K
β = 116.56 (3)°	Prism, colourless
V = 719.3 (8) Å^3	0.12 × 0.10 × 0.10 mm
Z = 4

Data collection

Enraf-Nonius CAD-4 diffractometer	Rint = 0.000
Radiation source: fine-focus sealed tube, Enraf-Nonius X-ray Generator	θmax = 25.3°, θmin = 3.3°
Graphite monochromator	h = −10→8
ω scan	k = 0→12
653 measured reflections	l = 0→10
653 independent reflections	3 standard reflections every 10800 min
652 reflections with I > 2σ(I)	intensity decay: 5.0%

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F^2 > 2σ(F^2)] = 0.028	H atoms treated by a mixture of independent and constrained refinement
wR(F^2) = 0.074	w = 1/[σ^2(Fo^2) + (0.0173P)^2 + 8.9338P] where P = (Fo^2 + 2Fc^2)/3
S = 1.15	(Δ/σ)max = 0.013
653 reflections	Δρmax = 0.67 e Å^−3
108 parameters	Δρmin = −0.79 e Å^−3
4 restraints	Absolute structure: Flack (1983)
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: 0.02 (3)

Special details

Experimental. Several crystals have been tested, all showing extreme mosaicity and heavily broadened, multiple peaks in the ω axis. Eventually, a (nearly) single-crystal specimen was found, which allowed a satisfactory unit cell determination, although with far from ideal e.s.d.'s. Of the several data collections performed with increasing ω scan width, the best results, reported hereafter, were obtained by the omega scan method with a rather unconventional scan angle of Δω=6.0 + 0.35tanθ°, 150 s per reflection (see the caption of Figure 3 for a further comment). Data collection performed with an Enraf–Nonius CAD-4 four-circle diffractometer equipped with a scintillation counter, sealed X-ray tube with Mo Kα radiation, graphite monochromator. Lattice parameters obtained by the indexing and least-squares refinement procedures of the setting angles of 25 strong reflections randomly distributed in the 9<θ<12° range. No absorption correction was applied. Powder diffraction data (Cu Kα radiation) were collected on the bulk sample, in order to test sample purity, crystal mosaicity and to confirm the unit cell proposed above. The relevant comments are reported in the caption to Fig.3.

Geometry. All e.s.d.'s 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.

Refinement. Refinement of F² against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F², conventional R-factors R are based on F, with F set to zero for negative F². The threshold expression of F² > σ(F²) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F² are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
Zn	0.00150 (9)	0.14440 (7)	0.55754 (9)	0.02306 (17)
S1	0.0926 (2)	0.34050 (17)	0.8285 (2)	0.0264 (4)
S2	0.2006 (2)	0.02396 (17)	0.3735 (2)	0.0259 (4)
O1	0.1286 (7)	0.3027 (5)	0.6808 (6)	0.0276 (12)
O2	0.2496 (6)	0.2991 (5)	0.9910 (6)	0.0284 (12)
O3	0.3197 (6)	0.5296 (5)	0.9125 (6)	0.0323 (14)
C1	0.1364 (9)	0.5070 (8)	0.8371 (11)	0.034 (2)
H1A	0.0827	0.5408	0.7246	0.040*
H1B	0.0821	0.5479	0.8999	0.040*
O4	0.2039 (6)	0.0495 (5)	0.5419 (6)	0.0307 (13)
O5	0.0352 (7)	−0.0570 (5)	0.2720 (6)	0.0281 (12)
O6	−0.0117 (6)	0.2178 (5)	0.3204 (6)	0.0302 (13)
C2	0.1220 (11)	0.1736 (7)	0.2768 (10)	0.0343 (18)
H2A	0.2213	0.2316	0.3147	0.041*
H2B	0.0727	0.1662	0.1562	0.041*
H3	0.336 (3)	0.518 (9)	0.829 (2)	0.07 (4)*
H6	−0.113 (3)	0.207 (7)	0.244 (5)	0.04 (3)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Zn	0.0225 (3)	0.0221 (3)	0.0231 (3)	0.0007 (4)	0.0089 (2)	0.0005 (4)
S1	0.0196 (7)	0.0254 (9)	0.0325 (9)	−0.0014 (7)	0.0101 (6)	−0.0049 (7)
S2	0.0218 (7)	0.0280 (9)	0.0272 (8)	−0.0009 (7)	0.0105 (6)	−0.0051 (7)
O1	0.029 (2)	0.025 (2)	0.026 (2)	−0.005 (2)	0.0094 (19)	−0.008 (2)
O2	0.028 (2)	0.029 (3)	0.026 (2)	−0.004 (2)	0.0103 (19)	−0.001 (2)
O3	0.029 (3)	0.031 (3)	0.036 (3)	−0.003 (2)	0.013 (2)	−0.003 (2)
C1	0.024 (4)	0.022 (3)	0.047 (4)	0.005 (3)	0.009 (3)	−0.001 (3)
O4	0.026 (2)	0.036 (3)	0.028 (2)	0.001 (2)	0.010 (2)	−0.007 (2)
O5	0.027 (2)	0.031 (3)	0.025 (2)	−0.008 (2)	0.0104 (19)	−0.006 (2)
O6	0.028 (2)	0.025 (3)	0.037 (3)	0.000 (2)	0.015 (2)	0.004 (2)
C2	0.039 (4)	0.028 (4)	0.043 (4)	−0.003 (3)	0.025 (3)	−0.001 (3)

Geometric parameters (Å, º)

Zn—O2^i	2.004 (5)	O2—Zn^iii	2.004 (5)
Zn—O4	2.031 (5)	O3—C1	1.388 (9)
Zn—O5^ii	2.040 (5)	O3—Zn^iii	2.398 (6)
Zn—O1	2.053 (5)	O3—H3	0.821 (11)
Zn—O6	2.219 (5)	C1—H1A	0.9700
Zn—O3^i	2.398 (6)	C1—H1B	0.9700
S1—O2	1.524 (5)	O5—Zn^iv	2.040 (5)
S1—O1	1.535 (6)	O6—C2	1.418 (10)
S1—C1	1.829 (9)	O6—H6	0.820 (10)
S2—O4	1.518 (5)	C2—H2A	0.9700
S2—O5	1.539 (5)	C2—H2B	0.9700
S2—C2	1.812 (8)
O2^i—Zn—O4	157.7 (2)	S1—O2—Zn^iii	122.2 (3)
O2^i—Zn—O5^ii	96.0 (2)	C1—O3—Zn^iii	114.6 (5)
O4—Zn—O5^ii	93.5 (2)	C1—O3—H3	97 (2)
O2^i—Zn—O1	97.3 (2)	Zn^iii—O3—H3	93 (5)
O4—Zn—O1	102.3 (2)	O3—C1—S1	110.4 (5)
O5^ii—Zn—O1	93.4 (2)	O3—C1—H1A	109.6
O2^i—Zn—O6	90.6 (2)	S1—C1—H1A	109.6
O4—Zn—O6	78.6 (2)	O3—C1—H1B	109.6
O5^ii—Zn—O6	171.8 (2)	S1—C1—H1B	109.6
O1—Zn—O6	90.5 (2)	H1A—C1—H1B	108.1
O2^i—Zn—O3^i	75.7 (2)	S2—O4—Zn	120.8 (3)
O4—Zn—O3^i	84.9 (2)	S2—O5—Zn^iv	121.9 (3)
O5^ii—Zn—O3^i	86.2 (2)	C2—O6—Zn	115.7 (4)
O1—Zn—O3^i	172.9 (2)	C2—O6—H6	111 (4)
O6—Zn—O3^i	90.79 (19)	Zn—O6—H6	110 (5)
O2—S1—O1	109.1 (3)	O6—C2—S2	109.2 (5)
O2—S1—C1	100.3 (3)	O6—C2—H2A	109.8
O1—S1—C1	100.6 (4)	S2—C2—H2A	109.8
O4—S2—O5	107.6 (3)	O6—C2—H2B	109.8
O4—S2—C2	98.9 (4)	S2—C2—H2B	109.8
O5—S2—C2	100.8 (3)	H2A—C2—H2B	108.3
S1—O1—Zn	115.5 (3)

Symmetry codes: (i) x−1/2, −y+1/2, z−1/2; (ii) x, −y, z+1/2; (iii) x+1/2, −y+1/2, z+1/2; (iv) x, −y, z−1/2.