Poly[diaqua-μ₄-acetyl­enedicarboxyl­ato-zinc(II)]

From a solution of [Zn(H₂O)₆](NO₃)₂ and acetyl­enedicarb­oxylic acid in deionized water, single crystals of zinc acetyl­ene­dicarboxyl­ate dihydrate, {[Zn(C₄O₄)(H₂O)₂]}_n, were obtained by slow evaporation of the solvent. The asymmetric unit consits of one zinc cation which is located on a centre of symmetry, half of an acetyl­enedicarboxyl­ate anion, the anion lying on a twofold axis, and one water mol­ecule in a general position. Thus, zinc is octa­hedrally coordinated by four O atoms of acetyl­enedicarboxyl­ate anions and two water mol­ecules in trans positions. These octa­hedra are connected by dicarboxyl­ate ligands into a three-dimensional network.

Key indicators

• Single-crystal X-ray study
• T = 295 K
• Mean [sigma](C-C) = 0.007 Å
• R factor = 0.042
• wR factor = 0.091
• Data-to-parameter ratio = 14.2

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT341_ALERT_3_C Low Bond Precision on C-C bonds (x 1000) Ang ...          7
PLAT371_ALERT_2_C Long   C(sp2)-C(sp1) Bond  C1     -   C2     ...       1.46 Ang.
PLAT731_ALERT_1_C Bond    Calc     0.82(6), Rep     0.82(2) ......       3.00 su-Rat
              O3   -H1      1.555   1.555
PLAT735_ALERT_1_C D-H     Calc     0.82(6), Rep     0.82(2) ......       3.00 su-Rat
              O3   -H1      1.555   1.555
PLAT736_ALERT_1_C H...A   Calc     2.06(6), Rep     2.06(2) ......       3.00 su-Rat
              H1   -O2      1.555   2.555

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

   3 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   1 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
   0 ALERT type 4 Improvement, methodology, query or suggestion

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Computing details

Data collection: X-AREA (Stoe & Cie, 2001); cell refinement: X-AREA; data reduction: X-AREA; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: DIAMOND (Brandenburg, 2001); software used to prepare material for publication: SHELXL97.

Poly[diaqua-µ₄-acetylenedicarboxylato-zinc(II)]

Crystal data

[Zn(C4O4)(H2O)2]	F(000) = 424
Mr = 213.44	Dx = 2.301 Mg m^−3
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2yc	Cell parameters from 2482 reflections
a = 13.245 (3) Å	θ = 6.3–59.2°
b = 7.223 (2) Å	µ = 3.96 mm^−1
c = 7.649 (2) Å	T = 295 K
β = 122.66 (1)°	Cube, colourless
V = 616.1 (3) Å^3	0.1 × 0.1 × 0.07 mm
Z = 4

Data collection

Stoe IPDS-II diffractometer	868 independent reflections
Radiation source: fine-focus sealed tube	551 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.092
φ scans	θmax = 29.6°, θmin = 3.4°
Absorption correction: numerical [X-RED (Stoe & Cie, 2001); the crystal shape was optimized using X-SHAPE (Stoe & Cie, 1999)]	h = −18→18
Tmin = 0.690, Tmax = 0.766	k = −9→10
5711 measured reflections	l = −10→10

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.042	All H-atom parameters refined
wR(F^2) = 0.091	w = 1/[σ^2(Fo^2) + (0.0395P)^2 + 0.4994P] where P = (Fo^2 + 2Fc^2)/3
S = 1.02	(Δ/σ)max < 0.001
868 reflections	Δρmax = 0.67 e Å^−3
61 parameters	Δρmin = −1.30 e Å^−3
2 restraints	Extinction correction: SHELXL97, Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0066 (14)

Special details

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.

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
Zn1	0.2500	0.2500	0.5000	0.0237 (2)
O1	0.2284 (3)	0.4834 (5)	0.1010 (5)	0.0347 (8)
O2	0.1289 (3)	0.2856 (4)	0.1802 (4)	0.0240 (7)
O3	0.1068 (3)	0.1323 (5)	0.4968 (6)	0.0335 (8)
C1	0.1413 (4)	0.3825 (6)	0.0557 (6)	0.0237 (8)
C2	0.0415 (4)	0.3751 (6)	−0.1614 (7)	0.0263 (9)
H1	0.041 (3)	0.177 (8)	0.460 (10)	0.06 (2)*
H2	0.133 (6)	0.075 (8)	0.605 (6)	0.06 (2)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Zn1	0.0214 (4)	0.0285 (4)	0.0179 (3)	0.0001 (4)	0.0086 (3)	−0.0010 (4)
O1	0.0301 (18)	0.0359 (18)	0.0256 (16)	−0.0119 (14)	0.0069 (14)	0.0057 (13)
O2	0.0231 (15)	0.029 (2)	0.0164 (12)	−0.0027 (11)	0.0083 (11)	0.0021 (10)
O3	0.0234 (19)	0.047 (2)	0.0303 (18)	0.0029 (15)	0.0146 (16)	0.0096 (15)
C1	0.025 (2)	0.0232 (19)	0.0190 (19)	0.0009 (16)	0.0095 (18)	−0.0014 (15)
C2	0.024 (2)	0.032 (2)	0.0210 (18)	−0.0029 (17)	0.0108 (17)	0.0018 (17)

Geometric parameters (Å, º)

Zn1—O3^i	2.067 (3)	O1—Zn1^iv	2.151 (3)
Zn1—O3	2.067 (3)	O2—C1	1.262 (5)
Zn1—O2^i	2.094 (3)	C1—C2	1.462 (6)
Zn1—O2	2.094 (3)	C2—C2^v	1.199 (9)
Zn1—O1^ii	2.151 (3)	O3—H1	0.82 (2)
Zn1—O1^iii	2.151 (3)	O3—H2	0.81 (2)
O1—C1	1.245 (5)
O3^i—Zn1—O3	180.0	O2^i—Zn1—O1^iii	98.23 (12)
O3^i—Zn1—O2^i	85.24 (13)	O2—Zn1—O1^iii	81.77 (12)
O3—Zn1—O2^i	94.76 (13)	O1^ii—Zn1—O1^iii	180.0
O3^i—Zn1—O2	94.76 (13)	C1—O1—Zn1^iv	135.0 (3)
O3—Zn1—O2	85.24 (13)	C1—O2—Zn1	128.3 (3)
O2^i—Zn1—O2	180.0	Zn1—O3—H1	130 (5)
O3^i—Zn1—O1^ii	85.80 (15)	Zn1—O3—H2	108 (5)
O3—Zn1—O1^ii	94.20 (15)	O1—C1—O2	126.4 (4)
O2^i—Zn1—O1^ii	81.77 (12)	O1—C1—C2	118.1 (4)
O2—Zn1—O1^ii	98.23 (12)	O2—C1—C2	115.5 (4)
O3^i—Zn1—O1^iii	94.20 (15)	C2^v—C2—C1	177.7 (4)
O3—Zn1—O1^iii	85.80 (15)	H1—O3—H2	110 (7)

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

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O3—H1···O2^vi	0.82 (2)	2.06 (2)	2.871 (5)	171 (7)
O3—H2···O1^i	0.81 (2)	2.04 (4)	2.771 (5)	150 (7)

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