Poly[bis­(μ₂-1H-imidazolyl-1,3-diyldiacetato-κ⁴O,O′:O′′′,O′′′')cadmium(II)]

In the title compound, [Cd(C₇H₇N₂O₄)₂]_n, C₇H₇N₂O₄⁻ zwitterions link Cd²⁺ cations into a network of [Cd(C₇H₇N₂O₄)₂]_n sheets. The carboxyl­ate arms of the ligand chelate to the metal, which shows square-anti­prismatic coordination. The Cd²⁺ ion occupies a special position 2 site symmetry. The crystals were found to be twinned.

Key indicators

• Single-crystal X-ray study
• T = 295 K
• Mean [sigma](Wave) = 0.000 Å
• R factor = 0.023
• wR factor = 0.053
• Data-to-parameter ratio = 14.6

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:      0.570     0.783
            Tmin(prime) and Tmax expected:      0.644     0.773
            RR(prime) =      0.873
            Please check that your absorption correction is appropriate.

   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
   1 ALERT type 3 Indicator that the structure quality may be low
   0 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: X-SEED (Barbour, 2001); software used to prepare material for publication: SHELXL97.

Poly[bis(µ₂-1H-imidazolyl-1,3-diyldiacetato-κ⁴O,O':O''',O'''')cadmium(II)]

Crystal data

[Cd(C7H7N2O4)2]	Dx = 2.001 Mg m^−3
Mr = 478.69	Mo Kα radiation, λ = 0.71073 Å
Tetragonal, I41/a	Cell parameters from 11950 reflections
Hall symbol: -I 4ad	θ = 3.4–27.5°
a = 14.9585 (4) Å	µ = 1.43 mm^−1
c = 14.2034 (4) Å	T = 295 K
V = 3178.11 (11) Å^3	Prism, colourless
Z = 8	0.30 × 0.24 × 0.18 mm
F(000) = 1904

Data collection

Rigaku R-AXIS RAPID IP diffractometer	1814 independent reflections
Radiation source: fine-focus sealed tube	1602 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.034
ω scans	θmax = 27.5°, θmin = 3.4°
Absorption correction: multi-scan (ABSCOR; Higashi, 1995)	h = −19→19
Tmin = 0.570, Tmax = 0.783	k = −19→19
15612 measured reflections	l = −18→18

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)] = 0.023	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.053	H-atom parameters constrained
S = 1.08	w = 1/[σ^2(Fo^2) + (0.0317P)^2 + 0.193P] where P = (Fo^2 + 2Fc^2)/3
1814 reflections	(Δ/σ)max = 0.001
124 parameters	Δρmax = 0.29 e Å^−3
0 restraints	Δρmin = −0.37 e Å^−3

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

	x	y	z	Uiso*/Ueq
Cd1	1.0000	0.2500	0.36280 (2)	0.02957 (8)
O1	1.0087 (2)	0.1377 (1)	0.4771 (1)	0.0519 (5)
O2	0.8711 (1)	0.1905 (1)	0.4717 (1)	0.0466 (5)
O3	0.6122 (1)	−0.2714 (1)	0.5030 (2)	0.0469 (5)
O4	0.5778 (1)	−0.1304 (1)	0.4732 (1)	0.0387 (5)
N1	0.8191 (1)	0.0356 (1)	0.5805 (2)	0.0285 (5)
N2	0.7224 (1)	−0.0716 (2)	0.5825 (2)	0.0305 (6)
C1	0.9288 (2)	0.1403 (2)	0.5039 (2)	0.0333 (6)
C2	0.9068 (2)	0.0793 (2)	0.5865 (2)	0.0396 (7)
C3	0.7359 (2)	0.0748 (2)	0.5837 (2)	0.0388 (7)
C4	0.6758 (2)	0.0078 (2)	0.5855 (2)	0.0382 (7)
C5	0.8086 (2)	−0.0525 (2)	0.5788 (2)	0.0293 (5)
C6	0.6871 (2)	−0.1626 (2)	0.5915 (2)	0.0377 (7)
C7	0.6208 (2)	−0.1889 (2)	0.5160 (2)	0.0326 (6)
H2a	0.9525	0.0336	0.5909	0.048*
H2b	0.9090	0.1142	0.6441	0.048*
H3	0.7236	0.1357	0.5845	0.047*
H4	0.6140	0.0141	0.5882	0.046*
H5	0.8547	−0.0941	0.5755	0.035*
H6a	0.6584	−0.1683	0.6524	0.045*
H6b	0.7368	−0.2043	0.5900	0.045*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Cd1	0.0293 (1)	0.0242 (1)	0.0352 (1)	0.0030 (1)	0.000	0.000
O1	0.046 (1)	0.047 (1)	0.063 (1)	−0.003 (1)	0.023 (1)	0.010 (1)
O2	0.044 (1)	0.042 (1)	0.054 (1)	−0.009 (1)	−0.006 (1)	0.016 (1)
O3	0.046 (1)	0.033 (1)	0.062 (1)	−0.003 (1)	−0.011 (1)	−0.011 (1)
O4	0.038 (1)	0.041 (1)	0.037 (1)	−0.005 (1)	−0.007 (1)	0.003 (1)
N1	0.026 (1)	0.031 (1)	0.028 (1)	−0.004 (1)	−0.001 (1)	0.005 (1)
N2	0.031 (1)	0.031 (1)	0.030 (1)	−0.006 (1)	−0.002 (1)	0.000 (1)
C1	0.039 (1)	0.031 (1)	0.030 (1)	−0.014 (1)	0.003 (1)	−0.004 (1)
C2	0.031 (2)	0.049 (2)	0.039 (1)	−0.010 (1)	−0.004 (1)	0.011 (1)
C3	0.034 (2)	0.031 (2)	0.051 (2)	0.005 (2)	0.009 (2)	−0.007 (1)
C4	0.027 (1)	0.041 (2)	0.047 (2)	−0.003 (2)	0.008 (1)	−0.009 (2)
C5	0.026 (2)	0.035 (2)	0.028 (1)	0.001 (1)	−0.002 (1)	0.005 (1)
C6	0.040 (2)	0.032 (2)	0.041 (1)	−0.011 (1)	−0.009 (1)	0.007 (1)
C7	0.026 (1)	0.037 (1)	0.035 (2)	−0.006 (1)	0.006 (1)	−0.003 (1)

Geometric parameters (Å, º)

Cd1—O1	2.339 (2)	N1—C2	1.469 (3)
Cd1—O1^i	2.339 (2)	N2—C5	1.322 (4)
Cd1—O2	2.627 (2)	N2—C4	1.379 (4)
Cd1—O2^i	2.627 (2)	N2—C6	1.466 (3)
Cd1—O3^ii	2.372 (2)	C1—C2	1.522 (4)
Cd1—O3^iii	2.372 (2)	C3—C4	1.346 (3)
Cd1—O4^ii	2.460 (2)	C6—C7	1.512 (4)
Cd1—O4^iii	2.460 (2)	C2—H2a	0.97
O1—C1	1.255 (3)	C2—H2b	0.97
O2—C1	1.232 (3)	C3—H3	0.93
O3—C7	1.254 (4)	C4—H4	0.93
O4—C7	1.245 (3)	C5—H5	0.93
N1—C5	1.327 (4)	C6—H6a	0.97
N1—C3	1.375 (4)	C6—H6b	0.97
O1—Cd1—O1^i	92.1 (1)	C5—N1—C2	123.3 (2)
O1—Cd1—O2	52.3 (1)	C3—N1—C2	128.0 (2)
O1—Cd1—O2^i	78.1 (1)	C5—N2—C4	107.9 (3)
O1—Cd1—O3^ii	88.9 (1)	C5—N2—C6	123.8 (2)
O1—Cd1—O3^iii	169.1 (1)	C4—N2—C6	128.0 (2)
O1—Cd1—O4^ii	88.0 (1)	O2—C1—O1	124.9 (3)
O1—Cd1—O4^iii	136.5 (1)	O2—C1—C2	120.0 (3)
O1^i—Cd1—O2	78.1 (1)	O1—C1—C2	114.9 (3)
O1^i—Cd1—O2^i	52.3 (1)	N1—C2—C1	114.5 (2)
O1^i—Cd1—O3^ii	169.1 (1)	C4—C3—N1	106.7 (3)
O1^i—Cd1—O3^iii	88.9 (1)	C3—C4—N2	107.7 (3)
O1^i—Cd1—O4^ii	136.5 (1)	N2—C5—N1	109.2 (2)
O1^i—Cd1—O4^iii	88.0 (1)	N2—C6—C7	114.6 (2)
O2—Cd1—O2^i	107.9 (1)	O4—C7—O3	124.5 (3)
O2—Cd1—O3^ii	94.0 (1)	O4—C7—C6	120.1 (2)
O2—Cd1—O3^iii	138.3 (1)	O3—C7—C6	115.3 (3)
O2—Cd1—O4^ii	131.8 (1)	N1—C2—H2a	108.6
O2—Cd1—O4^iii	85.3 (1)	C1—C2—H2a	108.6
O2^i—Cd1—O3^ii	138.3 (1)	N1—C2—H2b	108.6
O2^i—Cd1—O3^iii	94.0 (1)	C1—C2—H2b	108.6
O2^i—Cd1—O4^ii	85.3 (1)	H2a—C2—H2b	107.6
O2^i—Cd1—O4^iii	131.8 (1)	C4—C3—H3	126.7
O3^ii—Cd1—O3^iii	92.2 (1)	N1—C3—H3	126.7
O3^ii—Cd1—O4^ii	54.5 (1)	C3—C4—H4	126.2
O3^ii—Cd1—O4^iii	83.8 (1)	N2—C4—H4	126.2
O3^iii—Cd1—O4^ii	83.8 (1)	N2—C5—H5	125.4
O3^iii—Cd1—O4^iii	54.5 (1)	N1—C5—H5	125.4
O4^ii—Cd1—O4^iii	120.4 (1)	N2—C6—H6a	108.6
C1—O1—Cd1	97.8 (2)	C7—C6—H6a	108.6
C1—O2—Cd1	84.9 (2)	N2—C6—H6b	108.6
C7—O3—Cd1^iv	92.4 (2)	C7—C6—H6b	108.6
C7—O4—Cd1^iv	88.6 (2)	H6a—C6—H6b	107.6
C5—N1—C3	108.5 (2)
O1^i—Cd1—O1—C1	72.9 (2)	O2—C1—C2—N1	42.2 (4)
O3^ii—Cd1—O1—C1	−96.2 (2)	O1—C1—C2—N1	−141.3 (3)
O3^iii—Cd1—O1—C1	168.1 (3)	C5—N1—C3—C4	1.0 (4)
O4^ii—Cd1—O1—C1	−150.7 (2)	C2—N1—C3—C4	−173.7 (3)
O4^iii—Cd1—O1—C1	−16.4 (2)	N1—C3—C4—N2	−0.6 (4)
O2^i—Cd1—O1—C1	123.7 (2)	C5—N2—C4—C3	−0.1 (4)
O2—Cd1—O1—C1	−0.3 (2)	C6—N2—C4—C3	173.9 (3)
O1^i—Cd1—O2—C1	−101.8 (2)	C4—N2—C5—N1	0.8 (3)
O1—Cd1—O2—C1	0.3 (2)	C6—N2—C5—N1	−173.6 (3)
O3^ii—Cd1—O2—C1	85.8 (2)	C3—N1—C5—N2	−1.1 (3)
O3^iii—Cd1—O2—C1	−176.4 (1)	C2—N1—C5—N2	173.9 (2)
O4^ii—Cd1—O2—C1	41.8 (2)	C5—N2—C6—C7	−125.3 (3)
O4^iii—Cd1—O2—C1	169.3 (2)	C4—N2—C6—C7	61.5 (4)
O2^i—Cd1—O2—C1	−58.2 (2)	Cd1^iv—O4—C7—O3	0.4 (3)
Cd1—O2—C1—O1	−0.6 (3)	Cd1^iv—O4—C7—C6	−177.7 (2)
Cd1—O2—C1—C2	175.5 (2)	Cd1^iv—O3—C7—O4	−0.4 (3)
Cd1—O1—C1—O2	0.6 (3)	Cd1^iv—O3—C7—C6	177.8 (2)
Cd1—O1—C1—C2	−175.7 (2)	N2—C6—C7—O4	−24.0 (4)
C5—N1—C2—C1	119.8 (3)	N2—C6—C7—O3	157.6 (3)
C3—N1—C2—C1	−66.1 (4)

Symmetry codes: (i) −x+2, −y+1/2, z; (ii) y+5/4, −x+3/4, −z+3/4; (iii) −y+3/4, x−1/4, −z+3/4; (iv) y+1/4, −x+3/4, −z+3/4.