metal-organic compounds
Poly[bis(μ-azido-κ2N1:N1)[μ-1,2-bis(imidazol-1-yl)ethane-κ2N3:N3′]cadmium]
aCollege of Chemistry, Chemical Engineering and Materials Science, Key Laboratory of Organic Synthesis of Jiangsu Province, Soochow University, Suzhou 215123, People's Republic of China
*Correspondence e-mail: libaolong@suda.edu.cn
In the title three-dimensional coordination polymer, [Cd(N3)2(C8H10N4)]n, the coordination geometry around the CdII atom is distorted octahedral. The CdII atom is coordinated by two N atoms from two cis-positioned bridging 1,2-bis(imidazol-1-yl)ethane (bime) ligands and four N atoms from four azide anions. Each azide ligand acts in an end-on bridging coordination mode. The azide ligands and CdII atoms form a one-dimensional zigzag chain constructed from four-membered [Cd(N3)2]n metallacycles extending along the a axis. These inorganic chains are connected with four other chains via bridging bime ligands to form a three-dimensional coordination network.
Related literature
For coordination polymers with intriguing structures, see: Batten & Robson (1998); Blake et al. (1999); Kitagawa et al. (2004). For coordination polymers with flexible ligands, see: Hoskins et al. (1997a,b). For azide coordination compounds and polymers, see: Ribas et al. (1999); Leibeling et al. (2004); Chen & Chen (2002); Mautner et al. (1997). For 1,2-bis(imidazol-1-yl)ethane (bime) coordination polymers, see: Zhang et al. (2005, 2008); Zhu et al. (2010).
Experimental
Crystal data
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Refinement
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Data collection: CrystalClear (Rigaku, 2000); cell CrystalClear; data reduction: CrystalClear; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL.
Supporting information
10.1107/S1600536812004370/gk2436sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536812004370/gk2436Isup2.hkl
An aqueous (20 mL) solution of Cd(NO3)2.4H2O (0.50 mmol) and NaN3 (1.0 mmol) was added to one side of a "H-shape" tube, and a methanolic solution (20 mL) of bime (0.50 mmol) was added to the another side of the "H-shape" tube. Colourless crystal were obtained after about one month. Anal. Calcd. for C8H10CdN10: C, 26.79; H, 2.81; N, 39.06%. Found: C, 26.68; H, 2.72; N, 38.98%.
H atoms were placed in idealized positions and refined as riding, with C—H distances of 0.99Å (ethyl) and 0.95Å (imidazole) with Uiso(H) = 1.2Ueq(C).
Data collection: CrystalClear (Rigaku, 2000); cell
CrystalClear (Rigaku, 2000); data reduction: CrystalClear (Rigaku, 2000); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).[Cd(N3)2(C8H10N4)] | F(000) = 704 |
Mr = 358.66 | Dx = 1.871 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71070 Å |
Hall symbol: -P 2ybc | Cell parameters from 4950 reflections |
a = 6.4565 (14) Å | θ = 3.2–25.4° |
b = 18.874 (4) Å | µ = 1.72 mm−1 |
c = 10.449 (2) Å | T = 153 K |
β = 90.485 (5)° | Block, colourless |
V = 1273.2 (5) Å3 | 0.36 × 0.17 × 0.15 mm |
Z = 4 |
Rigaku Mercury CCD diffractometer | 2324 independent reflections |
Radiation source: fine-focus sealed tube | 2190 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.029 |
ω scans | θmax = 25.3°, θmin = 3.2° |
Absorption correction: multi-scan (REQAB; Jacobson, 1998) | h = −7→7 |
Tmin = 0.576, Tmax = 0.783 | k = −22→21 |
12260 measured reflections | l = −12→12 |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.023 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.056 | H-atom parameters constrained |
S = 1.09 | w = 1/[σ2(Fo2) + (0.0271P)2 + 1.003P] where P = (Fo2 + 2Fc2)/3 |
2324 reflections | (Δ/σ)max < 0.001 |
172 parameters | Δρmax = 0.68 e Å−3 |
0 restraints | Δρmin = −0.39 e Å−3 |
[Cd(N3)2(C8H10N4)] | V = 1273.2 (5) Å3 |
Mr = 358.66 | Z = 4 |
Monoclinic, P21/c | Mo Kα radiation |
a = 6.4565 (14) Å | µ = 1.72 mm−1 |
b = 18.874 (4) Å | T = 153 K |
c = 10.449 (2) Å | 0.36 × 0.17 × 0.15 mm |
β = 90.485 (5)° |
Rigaku Mercury CCD diffractometer | 2324 independent reflections |
Absorption correction: multi-scan (REQAB; Jacobson, 1998) | 2190 reflections with I > 2σ(I) |
Tmin = 0.576, Tmax = 0.783 | Rint = 0.029 |
12260 measured reflections |
R[F2 > 2σ(F2)] = 0.023 | 0 restraints |
wR(F2) = 0.056 | H-atom parameters constrained |
S = 1.09 | Δρmax = 0.68 e Å−3 |
2324 reflections | Δρmin = −0.39 e Å−3 |
172 parameters |
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. |
x | y | z | Uiso*/Ueq | ||
Cd1 | 0.25318 (3) | 0.538064 (9) | 0.443664 (17) | 0.01313 (8) | |
N1 | 0.6247 (3) | 0.60924 (12) | 0.1163 (2) | 0.0180 (5) | |
N2 | 0.4047 (3) | 0.56039 (12) | 0.2487 (2) | 0.0173 (5) | |
N3 | 0.9231 (4) | 0.75635 (12) | −0.0341 (2) | 0.0214 (5) | |
N4 | 1.1350 (4) | 0.84573 (12) | −0.0646 (2) | 0.0203 (5) | |
N5 | 0.5555 (3) | 0.57080 (12) | 0.5537 (2) | 0.0174 (5) | |
N6 | 0.5556 (4) | 0.61004 (12) | 0.6435 (2) | 0.0210 (5) | |
N7 | 0.5618 (5) | 0.64938 (15) | 0.7285 (3) | 0.0419 (8) | |
N8 | −0.0515 (3) | 0.48306 (13) | 0.3709 (2) | 0.0194 (5) | |
N9 | −0.0800 (3) | 0.46469 (11) | 0.2657 (2) | 0.0163 (5) | |
N10 | −0.1107 (4) | 0.44775 (15) | 0.1588 (3) | 0.0344 (7) | |
C1 | 0.8087 (4) | 0.64601 (16) | 0.0693 (3) | 0.0228 (6) | |
H1A | 0.8769 | 0.6170 | 0.0030 | 0.027* | |
H1B | 0.9085 | 0.6534 | 0.1405 | 0.027* | |
C2 | 0.7448 (4) | 0.71673 (15) | 0.0134 (3) | 0.0244 (6) | |
H2A | 0.6452 | 0.7088 | −0.0578 | 0.029* | |
H2B | 0.6742 | 0.7450 | 0.0798 | 0.029* | |
C3 | 0.5867 (4) | 0.59166 (14) | 0.2384 (3) | 0.0182 (6) | |
H3A | 0.6786 | 0.6005 | 0.3081 | 0.022* | |
C4 | 0.3236 (4) | 0.55828 (15) | 0.1267 (3) | 0.0212 (6) | |
H4A | 0.1927 | 0.5388 | 0.1039 | 0.025* | |
C5 | 0.4581 (4) | 0.58817 (15) | 0.0439 (3) | 0.0223 (6) | |
H5A | 0.4405 | 0.5934 | −0.0460 | 0.027* | |
C6 | 0.9741 (4) | 0.82267 (14) | −0.0004 (3) | 0.0202 (6) | |
H6A | 0.9028 | 0.8497 | 0.0621 | 0.024* | |
C7 | 1.1899 (5) | 0.79080 (16) | −0.1438 (3) | 0.0322 (8) | |
H7A | 1.3012 | 0.7917 | −0.2027 | 0.039* | |
C8 | 1.0618 (5) | 0.73543 (17) | −0.1252 (3) | 0.0350 (8) | |
H8A | 1.0667 | 0.6908 | −0.1669 | 0.042* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Cd1 | 0.01024 (12) | 0.01476 (13) | 0.01442 (12) | 0.00040 (7) | 0.00091 (8) | 0.00122 (7) |
N1 | 0.0179 (12) | 0.0179 (12) | 0.0184 (12) | −0.0024 (9) | 0.0052 (10) | 0.0028 (9) |
N2 | 0.0180 (12) | 0.0174 (11) | 0.0164 (12) | 0.0028 (10) | 0.0023 (10) | 0.0012 (10) |
N3 | 0.0223 (13) | 0.0169 (12) | 0.0251 (13) | −0.0057 (10) | 0.0059 (11) | −0.0022 (10) |
N4 | 0.0184 (12) | 0.0173 (12) | 0.0252 (13) | −0.0019 (10) | 0.0036 (10) | −0.0013 (10) |
N5 | 0.0156 (12) | 0.0167 (12) | 0.0199 (12) | 0.0020 (9) | −0.0006 (10) | −0.0020 (10) |
N6 | 0.0192 (13) | 0.0205 (13) | 0.0233 (14) | −0.0054 (10) | 0.0037 (10) | 0.0033 (11) |
N7 | 0.063 (2) | 0.0351 (17) | 0.0281 (16) | −0.0174 (15) | 0.0124 (14) | −0.0144 (13) |
N8 | 0.0136 (12) | 0.0269 (13) | 0.0178 (13) | −0.0039 (10) | 0.0006 (10) | 0.0029 (11) |
N9 | 0.0108 (11) | 0.0136 (12) | 0.0246 (15) | −0.0019 (8) | 0.0031 (10) | 0.0020 (10) |
N10 | 0.0336 (16) | 0.0459 (17) | 0.0238 (16) | −0.0125 (13) | 0.0015 (12) | −0.0103 (13) |
C1 | 0.0167 (14) | 0.0288 (16) | 0.0231 (15) | −0.0040 (12) | 0.0042 (12) | 0.0038 (12) |
C2 | 0.0205 (15) | 0.0215 (15) | 0.0312 (16) | −0.0055 (12) | 0.0040 (13) | 0.0020 (13) |
C3 | 0.0161 (14) | 0.0204 (14) | 0.0182 (14) | 0.0016 (11) | −0.0005 (11) | 0.0010 (11) |
C4 | 0.0203 (15) | 0.0209 (14) | 0.0222 (15) | −0.0042 (12) | −0.0011 (12) | −0.0031 (12) |
C5 | 0.0252 (16) | 0.0241 (15) | 0.0177 (14) | −0.0061 (12) | 0.0001 (12) | −0.0012 (12) |
C6 | 0.0199 (15) | 0.0161 (14) | 0.0247 (15) | −0.0019 (11) | 0.0056 (12) | −0.0025 (11) |
C7 | 0.0392 (19) | 0.0233 (16) | 0.0345 (18) | −0.0055 (14) | 0.0204 (15) | −0.0058 (13) |
C8 | 0.049 (2) | 0.0218 (16) | 0.0344 (18) | −0.0084 (15) | 0.0219 (16) | −0.0103 (14) |
Cd1—N2 | 2.306 (2) | N5—Cd1iii | 2.397 (2) |
Cd1—N4i | 2.324 (2) | N6—N7 | 1.158 (3) |
Cd1—N5 | 2.340 (2) | N8—N9 | 1.166 (3) |
Cd1—N8 | 2.345 (2) | N8—Cd1ii | 2.377 (2) |
Cd1—N8ii | 2.377 (2) | N9—N10 | 1.177 (4) |
Cd1—N5iii | 2.397 (2) | C1—C2 | 1.513 (4) |
N1—C3 | 1.343 (3) | C1—H1A | 0.9900 |
N1—C5 | 1.369 (4) | C1—H1B | 0.9900 |
N1—C1 | 1.464 (4) | C2—H2A | 0.9900 |
N2—C3 | 1.320 (4) | C2—H2B | 0.9900 |
N2—C4 | 1.375 (4) | C3—H3A | 0.9500 |
N3—C6 | 1.341 (3) | C4—C5 | 1.355 (4) |
N3—C8 | 1.370 (4) | C4—H4A | 0.9500 |
N3—C2 | 1.463 (4) | C5—H5A | 0.9500 |
N4—C6 | 1.316 (4) | C6—H6A | 0.9500 |
N4—C7 | 1.375 (4) | C7—C8 | 1.348 (4) |
N4—Cd1iv | 2.324 (2) | C7—H7A | 0.9500 |
N5—N6 | 1.195 (3) | C8—H8A | 0.9500 |
N2—Cd1—N4i | 86.36 (8) | Cd1—N8—Cd1ii | 105.89 (9) |
N2—Cd1—N5 | 91.57 (8) | N8—N9—N10 | 178.4 (3) |
N4i—Cd1—N5 | 92.36 (8) | N1—C1—C2 | 109.1 (2) |
N2—Cd1—N8 | 98.95 (8) | N1—C1—H1A | 109.9 |
N4i—Cd1—N8 | 97.56 (8) | C2—C1—H1A | 109.9 |
N5—Cd1—N8 | 165.94 (8) | N1—C1—H1B | 109.9 |
N2—Cd1—N8ii | 171.89 (8) | C2—C1—H1B | 109.9 |
N4i—Cd1—N8ii | 90.38 (8) | H1A—C1—H1B | 108.3 |
N5—Cd1—N8ii | 95.98 (8) | N3—C2—C1 | 111.7 (2) |
N8—Cd1—N8ii | 74.11 (9) | N3—C2—H2A | 109.3 |
N2—Cd1—N5iii | 86.80 (8) | C1—C2—H2A | 109.3 |
N4i—Cd1—N5iii | 168.07 (8) | N3—C2—H2B | 109.3 |
N5—Cd1—N5iii | 78.07 (8) | C1—C2—H2B | 109.3 |
N8—Cd1—N5iii | 93.15 (8) | H2A—C2—H2B | 107.9 |
N8ii—Cd1—N5iii | 97.62 (8) | N2—C3—N1 | 111.0 (2) |
C3—N1—C5 | 107.7 (2) | N2—C3—H3A | 124.5 |
C3—N1—C1 | 126.2 (2) | N1—C3—H3A | 124.5 |
C5—N1—C1 | 126.1 (2) | C5—C4—N2 | 109.8 (2) |
C3—N2—C4 | 105.6 (2) | C5—C4—H4A | 125.1 |
C3—N2—Cd1 | 122.58 (18) | N2—C4—H4A | 125.1 |
C4—N2—Cd1 | 130.74 (18) | C4—C5—N1 | 105.8 (2) |
C6—N3—C8 | 106.9 (2) | C4—C5—H5A | 127.1 |
C6—N3—C2 | 125.5 (2) | N1—C5—H5A | 127.1 |
C8—N3—C2 | 127.5 (2) | N4—C6—N3 | 111.6 (2) |
C6—N4—C7 | 105.4 (2) | N4—C6—H6A | 124.2 |
C6—N4—Cd1iv | 123.63 (18) | N3—C6—H6A | 124.2 |
C7—N4—Cd1iv | 130.37 (19) | C8—C7—N4 | 109.6 (3) |
N6—N5—Cd1 | 122.96 (18) | C8—C7—H7A | 125.2 |
N6—N5—Cd1iii | 121.70 (18) | N4—C7—H7A | 125.2 |
Cd1—N5—Cd1iii | 101.93 (8) | C7—C8—N3 | 106.4 (3) |
N7—N6—N5 | 177.5 (3) | C7—C8—H8A | 126.8 |
N9—N8—Cd1 | 124.23 (19) | N3—C8—H8A | 126.8 |
N9—N8—Cd1ii | 129.46 (19) | ||
C3—N1—C1—C2 | −116.5 (3) | C3—N1—C5—C4 | 0.1 (3) |
C5—N1—C1—C2 | 61.8 (4) | C1—N1—C5—C4 | −178.4 (3) |
C6—N3—C2—C1 | −125.8 (3) | C7—N4—C6—N3 | −0.1 (3) |
C8—N3—C2—C1 | 58.2 (4) | Cd1iv—N4—C6—N3 | 172.20 (18) |
N1—C1—C2—N3 | 179.4 (2) | C8—N3—C6—N4 | 0.5 (3) |
C4—N2—C3—N1 | −0.1 (3) | C2—N3—C6—N4 | −176.2 (3) |
Cd1—N2—C3—N1 | −169.59 (17) | C6—N4—C7—C8 | −0.5 (4) |
C5—N1—C3—N2 | 0.0 (3) | Cd1iv—N4—C7—C8 | −172.0 (2) |
C1—N1—C3—N2 | 178.6 (2) | N4—C7—C8—N3 | 0.8 (4) |
C3—N2—C4—C5 | 0.2 (3) | C6—N3—C8—C7 | −0.8 (4) |
Cd1—N2—C4—C5 | 168.5 (2) | C2—N3—C8—C7 | 175.9 (3) |
N2—C4—C5—N1 | −0.2 (3) |
Symmetry codes: (i) x−1, −y+3/2, z+1/2; (ii) −x, −y+1, −z+1; (iii) −x+1, −y+1, −z+1; (iv) x+1, −y+3/2, z−1/2. |
Experimental details
Crystal data | |
Chemical formula | [Cd(N3)2(C8H10N4)] |
Mr | 358.66 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 153 |
a, b, c (Å) | 6.4565 (14), 18.874 (4), 10.449 (2) |
β (°) | 90.485 (5) |
V (Å3) | 1273.2 (5) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 1.72 |
Crystal size (mm) | 0.36 × 0.17 × 0.15 |
Data collection | |
Diffractometer | Rigaku Mercury CCD diffractometer |
Absorption correction | Multi-scan (REQAB; Jacobson, 1998) |
Tmin, Tmax | 0.576, 0.783 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 12260, 2324, 2190 |
Rint | 0.029 |
(sin θ/λ)max (Å−1) | 0.602 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.023, 0.056, 1.09 |
No. of reflections | 2324 |
No. of parameters | 172 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.68, −0.39 |
Computer programs: CrystalClear (Rigaku, 2000), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).
Cd1—N2 | 2.306 (2) | Cd1—N8 | 2.345 (2) |
Cd1—N4i | 2.324 (2) | Cd1—N8ii | 2.377 (2) |
Cd1—N5 | 2.340 (2) | Cd1—N5iii | 2.397 (2) |
N2—Cd1—N5 | 91.57 (8) |
Symmetry codes: (i) x−1, −y+3/2, z+1/2; (ii) −x, −y+1, −z+1; (iii) −x+1, −y+1, −z+1. |
Acknowledgements
This work was supported by the Natural Science Foundation of China (grant Nos. 21171126, 20671066), and the Funds of the Key Laboratory of Organic Synthesis Chemistry, Jiangsu Province, People's Republic of China.
References
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Coordination polymers have been paid great attention for their intriguing structures and potential applications as functional materials (Batten & Robson 1998; Kitagawa et al., 2004). The selection of ligand is very important for the design and construction of the coordination polymers. In contrast to the rigid ligands with little or no conformational freedom when they interact with the metal ions, the flexible ligands can adjust their conformations to the geometric requirements of the metal ions (Hoskins et al., 1997a,b).
The short anion ligand azide (N3-) is widely used to construct novel coordination polymers because its versatile coordination modes and the ability to mediate strong magnetic coupling (Ribas et al., 1999; Leibeling et al., 2004).
In our previous studies, we synthesized two CdII coordination polymers with the flexible ligand 1,2-bis(imidazol-1-yl)ethane (bime; Zhang et al., 2005; Zhang et al., 2008) and one CuII coordination polymer (Zhu et al., 2010). In order to extend our work, in the present paper we report the preparation and crystal structure of a novel three-dimensional cadmium(II) coordination polymer [Cd(bime)(N3)2]n (I) with the flexible ligand bime and short anion ligand azide.
The structure of (I) is a novel three-dimensional network. Each CdII atom is coordinated by six nitrogen atoms: two from two bime ligands in the cis-positions and the remaining four from four azide anions, in a distorted octahedral geometry (Fig. 1, Table 1).
The Cd—N bond lengths are in the range of 2.306 (2) - 2.397 (2) Å and do not vary much. The Cd—N (bime) lengths of 2.306 (2) and 2.324 (2)Å are corresponding to the values 2.2769 (17)Å in [Cd(bime)dca)2]n (dca = dicyanamide; Zhang, et al., 2005) and 2.2748 (18) Å in [Cd(phba)2(bime)(H2O)2]n (phba = 4-hydroxybenzoate; Zhang et al., 2008). There are two symmetry independent azide ligands and they both act in end-on (EO) bridging coordination mode. The EO-azide ligands are linear and asymmetric [bond angles N5—N6—N7 = 177.5 (3)° and N8—N9—N10 = 178.4 (3)°, bond lengths N5—N6 = 1.195 (3) Å, N6—N7 = 1.158 (3) Å, N8—N9 = 1.166 (3) Å and N9—N10 = 1.177 (4) Å].
The Cd—N (azide) bond lengths of 2.340 (2) to 2.397 (2)Å are similar to the corresponding values of 2.258 (7) and 2.335 (6) Å in [Cd(picolinato)(N3]n with only EO-azide (Mautner et al., 1997) and 2.404 (3) to 2.474 (3) Å in [Cd(N3)(4-aba)(H2O)]n with µ-1,1,3-azide (4-abaH = 4-aminobenzoic acid; Chen & Chen, 2002). The cis N—Cd—N bond angles are in the range of 74.11 (9) to 98.95 (8)°, deviating much from 90°.
A pair of azide ligands bridge the CdII atoms to form a [Cd2(N3)2] four-membered metallacycle. The neighboring metallacycles have a common CdII atom and form a one-dimensional inorganic zigzag chain [Cd(N3)2]n (Fig. 2). The Cd1···Cd1# and Cd1···Cd1& separations via the EO-azide ligands are 3.6804 (7) and 3.7688 (7) Å, respectively. There is one symmetry independent bime ligand in (I). The bime ligands exhibits the anti-conformation with the torsion angle N1—C1—C2—N3 of 179.4 (2)°. The Cd···Cd distances between CdII atoms bridged via bime ligands are 11.5566 (15) Å.
The bime ligands attached to the [Cd(N3)2]n chain point in four different directions (Fig. 3) binding to adjacent [Cd(N3)2 chain and generating a three-dimensional network (Fig. 4).