A two-dimensional cadmium(II) coordination polymer with unusual 4.8² topology: poly­[aqua­(μ₃-1H-imidazole-4,5-dicarboxyl­ato)cadmium(II)]

In the title coordination polymer, [Cd(C₅H₂N₂O₄)(H₂O)]_n, the Cd^II atom is six-coordinated by one N atom and four O atoms from three individual imidazole-4,5-dicarboxyl­ate (HIDC²⁻) anions and the O atom of a water mol­ecule. The HIDC²⁻ anion serves as a bridging ligand to link the Cd^II atoms into a two-dimensional network.

Key indicators

• Single-crystal X-ray study
• T = 295 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.017
• wR factor = 0.043
• Data-to-parameter ratio = 12.3

checkCIF/PLATON results

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Alert level C
PLAT720_ALERT_4_C Number of Unusual/Non-Standard Label(s) ........          2

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

   0 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
   0 ALERT type 3 Indicator that the structure quality may be low
   1 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

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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[aqua(µ₃-1H-imidazole-4,5-dicarboxylato)cadmium(II)]

Crystal data

[Cd(C5H2N2O4)(H2O)]	F(000) = 544
Mr = 284.50	Dx = 2.838 Mg m^−3
Monoclinic, P21/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 6209 reflections
a = 6.5915 (13) Å	θ = 3.3–27.5°
b = 9.950 (2) Å	µ = 3.27 mm^−1
c = 10.546 (2) Å	T = 295 K
β = 105.73 (3)°	Prism, colourless
V = 665.8 (2) Å^3	0.35 × 0.24 × 0.16 mm
Z = 4

Data collection

Rigaku R-AXIS RAPID diffractometer	1521 independent reflections
Radiation source: fine-focus sealed tube	1464 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.017
Detector resolution: 10.000 pixels mm^-1	θmax = 27.5°, θmin = 3.3°
ω scans	h = −8→8
Absorption correction: multi-scan (ABSCOR; Higashi, 1995)	k = −12→12
Tmin = 0.401, Tmax = 0.594	l = −13→13
6292 measured reflections

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)] = 0.017	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.043	H atoms treated by a mixture of independent and constrained refinement
S = 1.07	w = 1/[σ^2(Fo^2) + (0.0229P)^2 + 0.7764P] where P = (Fo^2 + 2Fc^2)/3
1521 reflections	(Δ/σ)max = 0.001
124 parameters	Δρmax = 0.55 e Å^−3
3 restraints	Δρmin = −0.44 e Å^−3

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
Cd1	0.11652 (2)	0.569624 (15)	0.168205 (14)	0.01680 (7)
O1	0.2553 (3)	0.78125 (16)	0.27063 (15)	0.0217 (3)
O1W	0.3852 (3)	0.6144 (2)	0.07243 (17)	0.0289 (4)
H1W1	0.362 (4)	0.619 (4)	−0.0107 (10)	0.043*
H1W2	0.5164 (19)	0.609 (4)	0.108 (3)	0.043*
O2	0.4111 (3)	0.88051 (15)	0.45851 (14)	0.0193 (3)
O3	0.3167 (2)	0.82876 (16)	0.70993 (15)	0.0208 (3)
O4	0.2760 (4)	0.6353 (2)	0.80767 (18)	0.0370 (5)
N1	0.2408 (3)	0.54092 (17)	0.38604 (17)	0.0148 (3)
N2	0.2487 (3)	0.48812 (17)	0.58876 (17)	0.0144 (3)
H2	0.2433	0.4404	0.6557	0.017*
C1	0.2237 (3)	0.4427 (2)	0.4666 (2)	0.0151 (4)
H1	0.1975	0.3534	0.4413	0.018*
C2	0.2821 (3)	0.6558 (2)	0.46193 (19)	0.0125 (4)
C3	0.2849 (3)	0.6246 (2)	0.5896 (2)	0.0130 (4)
C4	0.3169 (3)	0.78106 (19)	0.3924 (2)	0.0136 (4)
C5	0.2968 (3)	0.7015 (2)	0.7130 (2)	0.0176 (4)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Cd1	0.02340 (10)	0.01647 (10)	0.00905 (9)	0.00214 (6)	0.00186 (6)	−0.00235 (5)
O1	0.0342 (9)	0.0188 (7)	0.0110 (7)	−0.0072 (7)	0.0042 (6)	0.0011 (6)
O1W	0.0231 (8)	0.0457 (11)	0.0175 (8)	−0.0040 (8)	0.0048 (7)	−0.0032 (8)
O2	0.0300 (8)	0.0126 (7)	0.0131 (7)	−0.0058 (6)	0.0018 (6)	−0.0001 (6)
O3	0.0263 (8)	0.0187 (8)	0.0187 (8)	−0.0011 (6)	0.0084 (6)	−0.0071 (6)
O4	0.0666 (14)	0.0314 (10)	0.0178 (8)	−0.0055 (10)	0.0195 (9)	0.0005 (7)
N1	0.0200 (8)	0.0121 (7)	0.0123 (8)	−0.0007 (7)	0.0043 (6)	−0.0015 (6)
N2	0.0196 (8)	0.0128 (8)	0.0118 (8)	0.0002 (7)	0.0058 (6)	0.0034 (6)
C1	0.0187 (10)	0.0115 (9)	0.0150 (10)	−0.0012 (7)	0.0046 (8)	−0.0009 (7)
C2	0.0148 (9)	0.0119 (8)	0.0105 (9)	−0.0001 (7)	0.0028 (7)	−0.0013 (7)
C3	0.0152 (9)	0.0112 (9)	0.0128 (9)	0.0001 (7)	0.0040 (7)	0.0006 (7)
C4	0.0153 (9)	0.0126 (9)	0.0127 (9)	0.0003 (7)	0.0033 (7)	0.0004 (7)
C5	0.0200 (9)	0.0213 (10)	0.0119 (9)	0.0002 (8)	0.0048 (8)	−0.0025 (8)

Geometric parameters (Å, º)

Cd1—N1	2.2383 (18)	O4—C5	1.234 (3)
Cd1—O2^i	2.2865 (15)	N1—C1	1.320 (3)
Cd1—O1W	2.3073 (18)	N1—C2	1.379 (3)
Cd1—O2^ii	2.3122 (17)	N2—C1	1.333 (3)
Cd1—O3^ii	2.3649 (16)	N2—C3	1.378 (3)
Cd1—O1	2.4294 (16)	N2—H2	0.86
O1—C4	1.237 (3)	C1—H1	0.93
O1W—H1W1	0.85 (1)	C2—C3	1.377 (3)
O1W—H1W2	0.85 (1)	C2—C4	1.495 (3)
O2—C4	1.271 (2)	C3—C5	1.494 (3)
O3—C5	1.275 (3)
N1—Cd1—O2^i	116.35 (6)	C5—O3—Cd1^iv	121.79 (14)
N1—Cd1—O1W	111.29 (7)	C1—N1—C2	106.17 (17)
O2^i—Cd1—O1W	81.49 (7)	C1—N1—Cd1	133.12 (14)
N1—Cd1—O2^ii	164.91 (6)	C2—N1—Cd1	116.71 (13)
O2^i—Cd1—O2^ii	71.60 (6)	C1—N2—C3	108.45 (16)
O1W—Cd1—O2^ii	81.94 (6)	C1—N2—H2	125.8
N1—Cd1—O3^ii	87.44 (6)	C3—N2—H2	125.8
O2^i—Cd1—O3^ii	121.49 (6)	N1—C1—N2	111.15 (18)
O1W—Cd1—O3^ii	141.09 (6)	N1—C1—H1	124.4
O2^ii—Cd1—O3^ii	77.53 (6)	N2—C1—H1	124.4
N1—Cd1—O1	70.45 (6)	C3—C2—N1	109.18 (17)
O2^i—Cd1—O1	159.05 (6)	C3—C2—C4	134.80 (18)
O1W—Cd1—O1	77.65 (6)	N1—C2—C4	116.01 (17)
O2^ii—Cd1—O1	106.95 (6)	N2—C3—C2	105.04 (17)
O3^ii—Cd1—O1	77.27 (6)	N2—C3—C5	118.60 (18)
C4—O1—Cd1	115.99 (13)	C2—C3—C5	136.06 (19)
Cd1—O1W—H1W1	121 (2)	O1—C4—O2	122.84 (19)
Cd1—O1W—H1W2	127 (2)	O1—C4—C2	117.35 (17)
H1W1—O1W—H1W2	110.0 (16)	O2—C4—C2	119.79 (18)
C4—O2—Cd1^iii	111.73 (13)	O4—C5—O3	125.9 (2)
C4—O2—Cd1^iv	139.81 (13)	O4—C5—C3	116.1 (2)
Cd1^iii—O2—Cd1^iv	108.40 (6)	O3—C5—C3	117.91 (18)
N1—Cd1—O1—C4	−4.44 (15)	C1—N2—C3—C2	−0.7 (2)
O2^i—Cd1—O1—C4	−117.38 (18)	C1—N2—C3—C5	173.98 (18)
O1W—Cd1—O1—C4	−122.62 (16)	N1—C2—C3—N2	1.2 (2)
O2^ii—Cd1—O1—C4	159.90 (15)	C4—C2—C3—N2	−177.4 (2)
O3^ii—Cd1—O1—C4	87.38 (15)	N1—C2—C3—C5	−172.1 (2)
O2^i—Cd1—N1—C1	−33.7 (2)	C4—C2—C3—C5	9.4 (4)
O1W—Cd1—N1—C1	−124.6 (2)	Cd1—O1—C4—O2	173.23 (16)
O2^ii—Cd1—N1—C1	85.3 (3)	Cd1—O1—C4—C2	−5.1 (2)
O3^ii—Cd1—N1—C1	90.5 (2)	Cd1^iii—O2—C4—O1	13.1 (3)
O1—Cd1—N1—C1	167.9 (2)	Cd1^iv—O2—C4—O1	−163.68 (16)
O2^i—Cd1—N1—C2	172.39 (13)	Cd1^iii—O2—C4—C2	−168.62 (14)
O1W—Cd1—N1—C2	81.48 (16)	Cd1^iv—O2—C4—C2	14.6 (3)
O2^ii—Cd1—N1—C2	−68.7 (3)	C3—C2—C4—O1	−163.7 (2)
O3^ii—Cd1—N1—C2	−63.46 (15)	N1—C2—C4—O1	17.8 (3)
O1—Cd1—N1—C2	13.94 (14)	C3—C2—C4—O2	17.9 (3)
C2—N1—C1—N2	0.8 (2)	N1—C2—C4—O2	−160.57 (18)
Cd1—N1—C1—N2	−155.05 (15)	Cd1^iv—O3—C5—O4	120.7 (2)
C3—N2—C1—N1	−0.1 (2)	Cd1^iv—O3—C5—C3	−63.0 (2)
C1—N1—C2—C3	−1.3 (2)	N2—C3—C5—O4	1.1 (3)
Cd1—N1—C2—C3	159.23 (13)	C2—C3—C5—O4	173.7 (2)
C1—N1—C2—C4	177.60 (18)	N2—C3—C5—O3	−175.56 (19)
Cd1—N1—C2—C4	−21.9 (2)	C2—C3—C5—O3	−3.0 (4)

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

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O1W—H1W1···O4^v	0.85 (1)	1.85 (1)	2.696 (3)	173 (3)
O1W—H1W2···O3^vi	0.85 (1)	2.07 (2)	2.877 (3)	158 (3)
N2—H2···O3^vii	0.86	1.92	2.776 (2)	171

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