catena-Poly[[tetra­aqua­cadmium]-μ-5,5′-(1,4-phenyl­ene)di(tetra­zol-2-ido)-κ²N²:N^2′]

In the title compound, [Cd(C₈H₄N₈)(H₂O)₄]_n, 5,5′-(1,4-phenyl­ene)di(tetra­zol-2-ide) (L) ligands bridge Cd^II atoms into polymeric chains along [201]. The Cd^II atom is situated on an inversion centre and is coordinated by two N atoms from two L ligands and by four water O atoms in a distorted octa­hedral geometry. In the L ligand, the benzene ring resides on an inversion centre and the tetra­zole rings are twisted from its plane by 22.3 (1)°. An extensive hydrogen-bonding network formed by classical O—H...N and O—H...O inter­actions consolidates the crystal packing, linking the poymeric chains into a three-dimensional structure.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.007 Å
• R factor = 0.040
• wR factor = 0.085
• Data-to-parameter ratio = 12.5

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT232_ALERT_2_C Hirshfeld Test Diff (M-X)  Cd1    --  O2      ..        8.0 su
PLAT242_ALERT_2_C Check Low       Ueq as Compared to Neighbors for        Cd1
PLAT250_ALERT_2_C Large U3/U1 Ratio for Average U(i,j) Tensor ....        2.1
PLAT790_ALERT_4_C Centre of Gravity not Within Unit Cell: Resd.  #          1
              C8 H12 Cd N8 O4
PLAT906_ALERT_3_C Large K value in the Analysis of Variance ......      6.296
PLAT910_ALERT_3_C Missing # of FCF Reflections Below Th(Min) .....          1
PLAT911_ALERT_3_C Missing # FCF Refl Between THmin & STh/L=  0.595          2
PLAT975_ALERT_2_C Positive Residual Density at 0.99A from O1     .       0.45 eA-3
PLAT975_ALERT_2_C Positive Residual Density at 1.09A from O2     .       0.43 eA-3
PLAT976_ALERT_2_C Negative Residual Density at 0.52A from O2     .      -0.45 eA-3
PLAT976_ALERT_2_C Negative Residual Density at 0.60A from O2     .      -0.42 eA-3

Alert level G
PLAT004_ALERT_5_G Info: Polymeric Structure Found with Dimension .          1
PLAT005_ALERT_5_G No _iucr_refine_instructions_details  in the CIF          ?
PLAT007_ALERT_5_G Note: Number of Unrefined D-H Atoms ............          4
PLAT128_ALERT_4_G Alternate Setting of Space-group P21/c   .......      P21/n
PLAT199_ALERT_1_G Check the Reported _cell_measurement_temperature        293 K
PLAT200_ALERT_1_G Check the Reported   _diffrn_ambient_temperature        293 K
PLAT794_ALERT_5_G Note: Tentative Bond Valency for Cd1     (II)          1.87
PLAT909_ALERT_3_G Percentage of Observed Data at Theta(Max) still          57 Perc.
PLAT961_ALERT_5_G Dataset Contains no Negative Intensities .......          !

   0 ALERT level A = Most likely a serious problem - resolve or explain
   0 ALERT level B = A potentially serious problem, consider carefully
  11 ALERT level C = Check. Ensure it is not caused by an omission or oversight
   9 ALERT level G = General information/check it is not something unexpected

   2 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   7 ALERT type 2 Indicator that the structure model may be wrong or deficient
   4 ALERT type 3 Indicator that the structure quality may be low
   2 ALERT type 4 Improvement, methodology, query or suggestion
   5 ALERT type 5 Informative message, check

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S1. Comment

Over the last decade coordination frameworks with channels or pores have captivated great attention of chemists because of their potential applications in gas storage, separation, ion exchange and catalysis(Yaghi et al., 2003; Kitagawa et al., 2004; Ockwig et al., 2005). 1,4-Bis(tetrazol-5-yl)benzene, firstly synthesized and characterized by Tao et al. (2004), is now widely used for constructing coordination frameworks with channels or pores (Dinca et al., 2006; Ouellette et al., 2009; Liu et al., 2012). This paper concerns the reaction of cadmium(II) and 1,4-bis(tetrazol-5-yl)benzene, and the crystal structure of the product.

In the title compound (Fig. 1), the Cd^II ion is located at an inversion centre. It has a slightly distorted octahedral coordination geometry formed by four water molecules and two nitrogen atoms from ligands L, where H₂L = 1,4-bis(tetrazol-5-yl)benzene. Four oxygen atoms form a planar parallelogram arrangement around the Cd centre, and the other two nitrogen atoms occupy the apical position. Each ligand L coordinates two cadmium atoms in a µ₂-bridging mode, thus generating a one-dimension coordination polymer. As far as we known, this coordination mode is currently unknown for L ligand.

In the crystal, polymeric one-dimensional chains are linked via O—H···N hydrogen bonds (Table 1) into a three-dimensional structure. The results show that there are no channels in the crystal structure.

Related literature

For background to coordination frameworks, see: Yaghi et al. (2003); Kitagawa et al. (2004); Ockwig et al. (2005). For details of the synthesis of 1,4-bis(tetrazole-5-yl)benzene, see: Tao et al. (2004). For the crystal structures of coordination polymers containing the 1,4-bis(tetrazole-5-yl)benzene ligand, see: Dinca et al. (2006); Ouellette et al. (2009); Liu et al. (2012).

S2. Experimental

Cadmium nitrate tetrahydrate (0.123 g, 0.40 mmol), 1,4-bis(tetrazole-5-yl)benzene (0.042 g, 0.20 mmol) and sodium hydroxide (0.016, 0.40 mmol) were added to 8 ml of water:ammonium hydroxide (v:v=1:1) mixture. The solution was transferred into a Teflon-lined stainless steel autoclave and the autoclave was heated to 393 K and maintained at that temperature for 72 h. After cooling to room temperature, crystals suitable for X-ray diffraction were collected.

S3. Refinement

Water hydrogen atoms were placed in calculated positions [O—H = 0.85–0.87 Å], and refined as riding, with U_iso(H) = 1.5 U_eq(O). The aromatic H atoms were positioned geometrically [C—H = 0.93 Å], and refined using a riding model, with U_iso(H) = 1.2 U_eq(C).

Computing details

Data collection: CrysAlis PRO (Agilent, 2012); cell refinement: CrysAlis PRO (Agilent, 2012); data reduction: CrysAlis PRO (Agilent, 2012); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg & Putz, 2006); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures

Fig. 1. A portion of the polymeric chain in the title compound showing the atomic numbering [symmetry codes: (a) 1-x , 1-y, 1-z; (b) -1-x, 1-y, -z]. Displacement ellipsoids are drawn at the 50% probability level.

catena-Poly[[tetraaquacadmium]-µ-5,5'-(1,4-phenylene)di(tetrazol-2-ido)-κ²N²:N^2']

Crystal data

[Cd(C8H4N8)(H2O)4]	F(000) = 392
Mr = 396.66	2013-04-07 # Formatted by publCIF
Monoclinic, P21/n	Dx = 1.883 Mg m^−3
Hall symbol: -P 2yn	Mo Kα radiation, λ = 0.71073 Å
a = 5.3188 (4) Å	Cell parameters from 739 reflections
b = 11.1525 (14) Å	θ = 3.5–29.1°
c = 12.0279 (8) Å	µ = 1.59 mm^−1
β = 101.256 (7)°	T = 293 K
V = 699.75 (11) Å^3	Prism, yellow
Z = 2	0.25 × 0.20 × 0.15 mm

Data collection

Agilent Xcalibur (Eos, Gemini) diffractometer	1237 independent reflections
Radiation source: fine-focus sealed tube	895 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.033
Detector resolution: 16.0710 pixels mm^-1	θmax = 25.0°, θmin = 3.5°
ω scans	h = −5→6
Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2012)	k = −5→13
Tmin = 0.692, Tmax = 0.796	l = −13→14
2351 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)] = 0.040	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.085	H-atom parameters constrained
S = 1.05	w = 1/[σ^2(Fo^2) + (0.0301P)^2] where P = (Fo^2 + 2Fc^2)/3
1237 reflections	(Δ/σ)max < 0.001
99 parameters	Δρmax = 0.62 e Å^−3
0 restraints	Δρmin = −0.53 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	0.5000	0.5000	0.5000	0.0273 (2)
O1	0.7271 (6)	0.6312 (4)	0.4040 (3)	0.0365 (10)
H1A	0.6261	0.6859	0.3696	0.055*
H1B	0.7918	0.5921	0.3544	0.055*
N1	0.0067 (7)	0.5049 (4)	0.2701 (3)	0.0266 (10)
N4	0.0598 (8)	0.3375 (4)	0.1802 (4)	0.0369 (12)
C2	−0.2949 (9)	0.4694 (5)	0.0882 (4)	0.0279 (13)
C4	−0.3166 (9)	0.4199 (5)	−0.0197 (4)	0.0333 (13)
H4	−0.1933	0.3658	−0.0335	0.040*
N2	0.2066 (7)	0.4426 (4)	0.3287 (4)	0.0327 (11)
C1	−0.0782 (9)	0.4371 (5)	0.1798 (4)	0.0286 (12)
N3	0.2401 (8)	0.3426 (4)	0.2768 (4)	0.0403 (12)
O2	0.2732 (8)	0.6693 (4)	0.5307 (4)	0.0659 (14)
H2A	0.3484	0.7038	0.5914	0.099*
H2B	0.1225	0.6488	0.5376	0.099*
C3	−0.4828 (10)	0.5505 (5)	0.1061 (4)	0.0342 (13)
H3	−0.4724	0.5849	0.1773	0.041*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Cd1	0.0262 (3)	0.0279 (3)	0.0244 (3)	0.0008 (3)	−0.0036 (2)	−0.0009 (3)
O1	0.034 (2)	0.041 (3)	0.034 (2)	0.0078 (17)	0.0051 (18)	0.0042 (19)
N1	0.021 (2)	0.036 (3)	0.019 (2)	0.005 (2)	−0.0059 (17)	0.001 (2)
N4	0.039 (3)	0.033 (3)	0.031 (3)	0.008 (2)	−0.013 (2)	−0.005 (2)
C2	0.023 (3)	0.034 (4)	0.024 (3)	−0.003 (2)	−0.002 (2)	0.001 (2)
C4	0.030 (3)	0.036 (4)	0.030 (3)	0.008 (3)	−0.004 (2)	−0.002 (3)
N2	0.031 (2)	0.039 (3)	0.025 (2)	0.001 (2)	−0.004 (2)	0.001 (2)
C1	0.027 (3)	0.035 (3)	0.020 (3)	0.000 (3)	−0.002 (2)	0.002 (3)
N3	0.042 (3)	0.036 (3)	0.034 (3)	0.005 (2)	−0.014 (2)	−0.003 (2)
O2	0.047 (2)	0.062 (3)	0.084 (4)	0.001 (2)	0.001 (2)	−0.019 (3)
C3	0.039 (3)	0.041 (4)	0.018 (3)	0.006 (3)	−0.006 (2)	−0.006 (3)

Geometric parameters (Å, º)

Cd1—O2^i	2.309 (4)	N4—N3	1.355 (5)
Cd1—O2	2.309 (4)	C2—C4	1.394 (7)
Cd1—O1	2.340 (3)	C2—C3	1.396 (7)
Cd1—O1^i	2.340 (3)	C2—C1	1.475 (7)
Cd1—N2	2.416 (4)	C4—C3^ii	1.377 (7)
Cd1—N2^i	2.416 (4)	C4—H4	0.9300
O1—H1A	0.8631	N2—N3	1.307 (6)
O1—H1B	0.8625	O2—H2A	0.8527
N1—C1	1.328 (6)	O2—H2B	0.8526
N1—N2	1.348 (6)	C3—C4^ii	1.377 (7)
N4—C1	1.331 (6)	C3—H3	0.9300
O2^i—Cd1—O2	179.999 (1)	C4—C2—C3	117.9 (5)
O2^i—Cd1—O1	95.51 (15)	C4—C2—C1	120.6 (4)
O2—Cd1—O1	84.49 (15)	C3—C2—C1	121.4 (5)
O2^i—Cd1—O1^i	84.49 (15)	C3^ii—C4—C2	121.3 (5)
O2—Cd1—O1^i	95.51 (15)	C3^ii—C4—H4	119.4
O1—Cd1—O1^i	180.0	C2—C4—H4	119.4
O2^i—Cd1—N2	85.26 (16)	N3—N2—N1	110.9 (4)
O2—Cd1—N2	94.74 (16)	N3—N2—Cd1	120.5 (3)
O1—Cd1—N2	93.12 (13)	N1—N2—Cd1	128.4 (3)
O1^i—Cd1—N2	86.88 (13)	N1—C1—N4	111.9 (4)
O2^i—Cd1—N2^i	94.74 (16)	N1—C1—C2	124.3 (5)
O2—Cd1—N2^i	85.26 (16)	N4—C1—C2	123.8 (5)
O1—Cd1—N2^i	86.88 (13)	N2—N3—N4	107.8 (4)
O1^i—Cd1—N2^i	93.12 (13)	Cd1—O2—H2A	109.5
N2—Cd1—N2^i	180.0 (3)	Cd1—O2—H2B	109.1
Cd1—O1—H1A	110.2	H2A—O2—H2B	109.3
Cd1—O1—H1B	109.8	C4^ii—C3—C2	120.8 (5)
H1A—O1—H1B	108.7	C4^ii—C3—H3	119.6
C1—N1—N2	104.0 (4)	C2—C3—H3	119.6
C1—N4—N3	105.4 (4)

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

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1B···N1^iii	0.86	1.93	2.779 (5)	167
O1—H1A···N4^iv	0.86	1.99	2.836 (6)	166
O2—H2A···N3^i	0.85	2.49	3.121 (6)	131
O2—H2B···O1^v	0.85	2.39	3.035 (6)	133

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