Twinned poly­[[di­aqua­calcium(II)]-μ₄-benzene-1,3-dioxy­acetato]

The water-coordinated Ca atom in the layer structure of the title compound, [Ca(C₁₀H₈O₆)(H₂O)₂]_n, is connected to a carboxyl O atom of one —O—CH₂—CO₂ arm of the di­carboxyl­ate dianion; it is also linked to an O atom of a carboxyl­ate group of this arm of an adjacent dianion, as well as to the O atoms of the other arm of two different dianions. The six-coordinate octahedral geometry is distorted, owing to a weak interaction with the ether O atom of one of the arms; the dianion functions in a μ₄-bridging mode.

Key indicators

• Single-crystal X-ray study
• T = 295 K
• Mean [sigma](C-C) = 0.009 Å
• R factor = 0.061
• wR factor = 0.203
• Data-to-parameter ratio = 12.4

checkCIF/PLATON results

No syntax errors found



Alert level C
ABSTM02_ALERT_3_C  The ratio of expected to reported Tmax/Tmin(RR') is < 0.90
            Tmin and Tmax reported:      0.638     0.923
            Tmin' and Tmax expected:      0.806     0.922
            RR' =      0.791
            Please check that your absorption correction is appropriate.
PLAT042_ALERT_1_C Calc. and Rep. MoietyFormula Strings Differ ....          ?
PLAT061_ALERT_3_C Tmax/Tmin Range Test RR' too Large .............       0.79
PLAT127_ALERT_1_C Implicit Hall Symbol  Inconsistent with Explicit     -P 2yc
PLAT152_ALERT_1_C Supplied and Calc Volume s.u. Inconsistent .....          ?
PLAT242_ALERT_2_C Check Low       Ueq as Compared to Neighbors for        Ca1
PLAT341_ALERT_3_C Low Bond Precision on C-C bonds (x 1000) Ang ...          9
PLAT720_ALERT_4_C Number of Unusual/Non-Standard Label(s) ........          4

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   8 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
   3 ALERT type 3 Indicator that the structure quality may be low
   1 ALERT type 4 Improvement, methodology, query or suggestion

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Computing details

Data collection: RAPID-AUTO (Rigaku, 1998); cell refinement: RAPID-AUTO; data reduction: CrystalStructure (Rigaku/MSC, 2002); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEPII (Johnson, 1976); software used to prepare material for publication: SHELXL97.

poly[[diaquacalcium(II)]-µ₄-benzene-1,3-dioxyacetato]

Crystal data

[Ca(C10H8O6)(H2O)2]	F(000) = 624
Mr = 300.28	Dx = 1.623 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yc	Cell parameters from 9802 reflections
a = 15.795 (3) Å	θ = 3.3–27.5°
b = 7.917 (2) Å	µ = 0.54 mm^−1
c = 9.829 (2) Å	T = 295 K
β = 90.65 (3)°	Prism, colorless
V = 1229.0 (4) Å^3	0.39 × 0.26 × 0.15 mm
Z = 4

Data collection

Rigaku R-AXIS-RAPID diffractometer	2153 independent reflections
Radiation source: fine-focus sealed tube	1933 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.040
ω scans	θmax = 25.0°, θmin = 3.3°
Absorption correction: multi-scan (ABSCOR; Higashi, 1995)	h = −18→18
Tmin = 0.638, Tmax = 0.923	k = −9→9
9687 measured reflections	l = −11→11

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.061	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.203	H-atom parameters constrained
S = 1.11	w = 1/[σ^2(Fo^2) + (0.1067P)^2 + 4.6656P] where P = (Fo^2 + 2Fc^2)/3
2153 reflections	(Δ/σ)max = 0.001
173 parameters	Δρmax = 0.38 e Å^−3
0 restraints	Δρmin = −0.96 e Å^−3

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

	x	y	z	Uiso*/Ueq
Ca1	0.6398 (1)	0.4604 (1)	0.315 (1)	0.0279 (4)
O1	0.6002 (3)	0.6325 (6)	0.4971 (5)	0.043 (1)
O2	0.6221 (3)	0.8152 (6)	0.6611 (6)	0.047 (1)
O3	0.7458 (3)	0.7036 (6)	0.3826 (5)	0.041 (1)
O4	0.8931 (3)	1.1001 (6)	0.0910 (5)	0.037 (1)
O5	0.6951 (3)	1.3101 (6)	0.1307 (5)	0.038 (1)
O6	0.7447 (3)	1.1687 (6)	−0.0463 (5)	0.043 (1)
O1w	0.5671 (3)	0.2318 (6)	0.4330 (6)	0.040 (1)
O2w	0.4985 (4)	0.4383 (8)	0.2220 (7)	0.059 (2)
C1	0.6406 (4)	0.7506 (8)	0.5503 (7)	0.031 (1)
C2	0.7146 (4)	0.8237 (8)	0.4755 (7)	0.037 (2)
C3	0.8124 (4)	0.7531 (8)	0.3015 (7)	0.033 (1)
C4	0.8728 (4)	0.6315 (8)	0.2781 (7)	0.037 (2)
C5	0.9380 (4)	0.6689 (8)	0.1874 (8)	0.040 (2)
C6	0.9426 (4)	0.8253 (8)	0.1263 (7)	0.036 (2)
C7	0.8824 (4)	0.9469 (8)	0.1557 (7)	0.032 (2)
C8	0.8161 (4)	0.9121 (9)	0.2433 (8)	0.037 (2)
C9	0.8408 (4)	1.2363 (8)	0.1334 (7)	0.034 (1)
C10	0.7529 (4)	1.2358 (8)	0.0674 (7)	0.031 (1)
H1w1	0.5192	0.2674	0.4599	0.048*
H1w2	0.5972	0.2034	0.5017	0.048*
H2w1	0.4620	0.4020	0.2775	0.070*
H2w2	0.4804	0.5268	0.1828	0.070*
H2a	0.6971	0.9248	0.4271	0.045*
H2b	0.7590	0.8545	0.5399	0.045*
H4	0.8704	0.5272	0.3214	0.044*
H5	0.9786	0.5874	0.1683	0.049*
H6	0.9859	0.8490	0.0658	0.043*
H8	0.7754	0.9934	0.2623	0.044*
H9a	0.8688	1.3419	0.1118	0.041*
H9b	0.8348	1.2310	0.2314	0.041*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Ca1	0.0276 (6)	0.0221 (6)	0.0340 (6)	0.0008 (5)	0.0046 (6)	0.0006 (5)
O1	0.038 (3)	0.043 (3)	0.048 (3)	−0.012 (2)	0.018 (2)	−0.016 (2)
O2	0.042 (3)	0.043 (3)	0.056 (3)	−0.008 (2)	0.014 (2)	−0.020 (2)
O3	0.041 (3)	0.026 (2)	0.058 (3)	−0.004 (2)	0.022 (2)	−0.004 (2)
O4	0.028 (2)	0.028 (2)	0.055 (3)	0.000 (2)	0.009 (2)	0.007 (2)
O5	0.035 (2)	0.039 (3)	0.041 (3)	0.010 (2)	0.007 (2)	−0.005 (2)
O6	0.035 (2)	0.051 (3)	0.043 (3)	0.004 (2)	0.000 (2)	−0.018 (2)
O1w	0.030 (2)	0.039 (3)	0.049 (3)	−0.009 (2)	−0.001 (2)	0.007 (2)
O2w	0.036 (3)	0.063 (4)	0.076 (5)	−0.008 (3)	−0.001 (3)	0.030 (3)
C1	0.026 (3)	0.024 (3)	0.041 (3)	0.003 (3)	0.005 (3)	−0.007 (3)
C2	0.038 (3)	0.030 (3)	0.044 (4)	−0.005 (3)	0.010 (3)	−0.007 (3)
C3	0.031 (3)	0.027 (3)	0.043 (4)	−0.003 (3)	0.011 (3)	0.000 (3)
C4	0.036 (3)	0.026 (3)	0.048 (4)	0.000 (3)	0.006 (3)	0.002 (3)
C5	0.028 (3)	0.032 (3)	0.061 (4)	0.008 (3)	0.004 (3)	−0.007 (3)
C6	0.025 (3)	0.033 (3)	0.050 (4)	0.001 (3)	0.010 (3)	0.000 (3)
C7	0.025 (3)	0.030 (3)	0.041 (4)	−0.005 (2)	0.004 (3)	0.000 (3)
C8	0.029 (3)	0.030 (3)	0.052 (4)	0.004 (3)	0.011 (3)	−0.002 (3)
C9	0.033 (3)	0.026 (3)	0.043 (3)	−0.004 (3)	−0.001 (3)	−0.002 (3)
C10	0.029 (3)	0.022 (3)	0.041 (3)	−0.002 (3)	0.000 (3)	−0.001 (3)

Geometric parameters (Å, º)

Ca1—O1	2.340 (5)	C4—C5	1.40 (1)
Ca1—O2^i	2.347 (5)	C5—C6	1.38 (1)
Ca1—O3	2.631 (5)	C6—C7	1.386 (9)
Ca1—O6^ii	2.365 (5)	C7—C8	1.392 (9)
Ca1—O5^iii	2.344 (5)	C9—C10	1.526 (9)
Ca1—O1w	2.443 (5)	O1w—H1w1	0.85
Ca1—O2w	2.409 (6)	O1w—H1w2	0.85
O1—C1	1.244 (8)	O2w—H2w1	0.85
O2—C1	1.241 (8)	O2w—H2w2	0.85
O3—C3	1.384 (8)	C2—H2a	0.97
O3—C2	1.410 (8)	C2—H2b	0.97
O4—C7	1.381 (8)	C4—H4	0.93
O4—C9	1.423 (8)	C5—H5	0.93
O5—C10	1.257 (8)	C6—H6	0.93
O6—C10	1.243 (9)	C8—H8	0.93
C1—C2	1.504 (9)	C9—H9a	0.97
C3—C4	1.377 (9)	C9—H9b	0.97
C3—C8	1.384 (9)
O1—Ca1—O2^i	91.2 (2)	C3—C4—C5	118.3 (6)
O1—Ca1—O3	63.6 (2)	C6—C5—C4	120.7 (6)
O1—Ca1—O5^iii	172.6 (2)	C5—C6—C7	119.6 (6)
O1—Ca1—O6^ii	90.1 (2)	O4—C7—C6	115.3 (5)
O1—Ca1—O1w	86.4 (2)	O4—C7—C8	123.7 (6)
O1—Ca1—O2w	94.5 (2)	C6—C7—C8	121.0 (6)
O2^i—Ca1—O3	71.3 (2)	C3—C8—C7	118.1 (6)
O2^i—Ca1—O5^iii	85.9 (2)	O4—C9—C10	113.7 (5)
O2^i—Ca1—O6^ii	140.9 (2)	O6—C10—O5	125.1 (6)
O2^i—Ca1—O1w	144.4 (2)	O6—C10—C9	118.0 (6)
O2^i—Ca1—O2w	73.0 (2)	O5—C10—C9	116.8 (6)
O3—Ca1—O5^iii	109.0 (2)	Ca1—O1w—H1w1	109.0
O3—Ca1—O6^ii	74.4 (2)	Ca1—O1w—H1w2	108.1
O3—Ca1—O1w	136.3 (2)	H1w1—O1w—H1w2	109.3
O3—Ca1—O2w	137.1 (2)	Ca1—O2w—H2w1	114.5
O5^iii—Ca1—O6^ii	87.8 (2)	Ca1—O2w—H2w2	114.8
O5^iii—Ca1—O1w	99.9 (2)	H2w1—O2w—H2w2	110.1
O5^iii—Ca1—O2w	91.2 (2)	O3—C2—H2a	109.7
O6^ii—Ca1—O1w	74.7 (2)	C1—C2—H2a	109.7
O6^ii—Ca1—O2w	145.8 (2)	O3—C2—H2b	109.7
O1w—Ca1—O2w	71.8 (2)	C1—C2—H2b	109.7
C1—O1—Ca1	128.3 (4)	H2a—C2—H2b	108.2
C1—O2—Ca1^ii	148.2 (5)	C3—C4—H4	120.9
C3—O3—C2	117.1 (5)	C5—C4—H4	120.9
C3—O3—Ca1	123.2 (4)	C6—C5—H5	119.7
C2—O3—Ca1	115.6 (4)	C4—C5—H5	119.7
C7—O4—C9	117.1 (5)	C5—C6—H6	120.2
C10—O5—Ca1^iv	154.0 (4)	C7—C6—H6	120.2
C10—O6—Ca1^i	140.2 (4)	C3—C8—H8	120.9
O2—C1—O1	123.7 (6)	C7—C8—H8	120.9
O2—C1—C2	117.6 (6)	O4—C9—H9a	108.8
O1—C1—C2	118.8 (6)	C10—C9—H9a	108.8
O3—C2—C1	109.6 (5)	O4—C9—H9b	108.8
C4—C3—C8	122.3 (6)	C10—C9—H9b	108.8
C4—C3—O3	115.5 (6)	H9a—C9—H9b	107.7
C8—C3—O3	122.1 (6)
O2^i—Ca1—O1—C1	−71.1 (6)	O1—C1—C2—O3	−23.0 (9)
O6^ii—Ca1—O1—C1	69.8 (6)	C2—O3—C3—C4	141.7 (6)
O2w—Ca1—O1—C1	−144.1 (6)	Ca1—O3—C3—C4	−62.4 (8)
O1w—Ca1—O1—C1	144.5 (6)	C2—O3—C3—C8	−41 (1)
O3—Ca1—O1—C1	−2.7 (5)	Ca1—O3—C3—C8	115.0 (6)
O1—Ca1—O3—C3	−167.0 (5)	C8—C3—C4—C5	−3 (1)
O5^iii—Ca1—O3—C3	12.8 (5)	O3—C3—C4—C5	174.6 (6)
O2^i—Ca1—O3—C3	−65.9 (5)	C3—C4—C5—C6	2 (1)
O6^ii—Ca1—O3—C3	94.9 (5)	C4—C5—C6—C7	0 (1)
O2w—Ca1—O3—C3	−101.0 (5)	C9—O4—C7—C6	−170.7 (6)
O1w—Ca1—O3—C3	141.4 (5)	C9—O4—C7—C8	10.1 (9)
O1—Ca1—O3—C2	−10.7 (4)	C5—C6—C7—O4	179.1 (7)
O5^iii—Ca1—O3—C2	169.1 (4)	C5—C6—C7—C8	−2 (1)
O2^i—Ca1—O3—C2	90.4 (5)	C4—C3—C8—C7	2 (1)
O6^ii—Ca1—O3—C2	−108.8 (5)	O3—C3—C8—C7	−175.6 (6)
O2w—Ca1—O3—C2	55.3 (6)	O4—C7—C8—C3	179.8 (6)
O1w—Ca1—O3—C2	−62.4 (5)	C6—C7—C8—C3	1 (1)
Ca1^ii—O2—C1—O1	−165.9 (6)	C7—O4—C9—C10	−82.6 (7)
Ca1^ii—O2—C1—C2	12.4 (13)	Ca1^i—O6—C10—O5	−28 (1)
Ca1—O1—C1—O2	−166.5 (5)	Ca1^i—O6—C10—C9	155.3 (5)
Ca1—O1—C1—C2	15.3 (9)	Ca1^iv—O5—C10—O6	−179.7 (6)
C3—O3—C2—C1	177.7 (6)	Ca1^iv—O5—C10—C9	−3 (1)
Ca1—O3—C2—C1	20.0 (7)	O4—C9—C10—O6	−27.0 (9)
O2—C1—C2—O3	158.7 (6)	O4—C9—C10—O5	155.8 (6)

Symmetry codes: (i) x, −y+3/2, z−1/2; (ii) x, −y+3/2, z+1/2; (iii) x, y−1, z; (iv) x, y+1, z.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O1w—H1w1···O1^v	0.85	2.09	2.942 (7)	173
O1w—H1w2···O5^ii	0.85	1.99	2.807 (7)	160
O2w—H2w1···O2^v	0.85	2.26	3.004 (7)	147
O2w—H2w2···O1w^vi	0.85	2.12	2.960 (8)	174

Symmetry codes: (ii) x, −y+3/2, z+1/2; (v) −x+1, −y+1, −z+1; (vi) −x+1, y+1/2, −z+1/2.