Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S0108270104005542/tr1078sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S0108270104005542/tr1078Isup2.hkl |
CCDC reference: 237920
A water/MeOH (1:1, v/v) solution (25 ml) of 1,2-bis(1,2,4-triazol-1-yl)ethane (0.082 g, 0.5 mmol) was added to one leg of a H-shaped tube and a water/MeOH (1:1, v/v) solution (25 ml) of NaN3 (0.078 g, 1.2 mmol) and Zn(NO3)2·6H2O (0.149 g, 0.5 mmol) was added to the other leg of the tube. Colourless crystals suitable for X-ray analysis were obtained after about three months. Analysis found: C 22.87, H 2.61, N 53.58%; calculated for C6H8N12Zn: C 22.98, H 2.57, N 53.61%.
H atoms were placed in idealized positions and refined as riding, with C—H distances of 0.95 (triazole) and 0.99 Å (ethane).
Data collection: CrystalClear (Rigaku, 2000); cell refinement: CrystalClear; data reduction: CrystalClear; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Bruker, 1998); software used to prepare material for publication: SHELXTL & DIAMOND (Brandenburg, 2000).
Fig. 1. A view of (I), drawn at the 50% probability level. [Symmetry codes: (i) 1 − x, 1 − y, 2 − z; (ii) −x, 1 − y, 2 − z; (iii) 1 + x, y, z.] | |
Fig. 2. The infinite one-dimensional chain of (I). |
[Zn(N3)2(C6H8N6)] | Z = 2 |
Mr = 313.61 | F(000) = 316 |
Triclinic, P1 | Dx = 1.805 Mg m−3 |
Hall symbol: -P 1 | Mo Kα radiation, λ = 0.71073 Å |
a = 7.646 (3) Å | Cell parameters from 2938 reflections |
b = 8.690 (3) Å | θ = 3.1–27.5° |
c = 9.266 (3) Å | µ = 2.14 mm−1 |
α = 95.430 (5)° | T = 193 K |
β = 105.054 (6)° | Block, colourless |
γ = 100.884 (5)° | 0.50 × 0.35 × 0.21 mm |
V = 577.1 (3) Å3 |
Rigaku Mercury CCD diffractometer | 2575 independent reflections |
Radiation source: fine-focus sealed tube | 2488 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.023 |
ω scans | θmax = 27.5°, θmin = 3.1° |
Absorption correction: multi-scan (North et al., 1968) | h = −9→9 |
Tmin = 0.412, Tmax = 0.638 | k = −11→10 |
6341 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)] = 0.025 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.063 | H-atom parameters constrained |
S = 1.06 | w = 1/[σ2(Fo2) + (0.0293P)2 + 0.4081P] where P = (Fo2 + 2Fc2)/3 |
2575 reflections | (Δ/σ)max = 0.001 |
172 parameters | Δρmax = 0.29 e Å−3 |
0 restraints | Δρmin = −0.41 e Å−3 |
[Zn(N3)2(C6H8N6)] | γ = 100.884 (5)° |
Mr = 313.61 | V = 577.1 (3) Å3 |
Triclinic, P1 | Z = 2 |
a = 7.646 (3) Å | Mo Kα radiation |
b = 8.690 (3) Å | µ = 2.14 mm−1 |
c = 9.266 (3) Å | T = 193 K |
α = 95.430 (5)° | 0.50 × 0.35 × 0.21 mm |
β = 105.054 (6)° |
Rigaku Mercury CCD diffractometer | 2575 independent reflections |
Absorption correction: multi-scan (North et al., 1968) | 2488 reflections with I > 2σ(I) |
Tmin = 0.412, Tmax = 0.638 | Rint = 0.023 |
6341 measured reflections |
R[F2 > 2σ(F2)] = 0.025 | 0 restraints |
wR(F2) = 0.063 | H-atom parameters constrained |
S = 1.06 | Δρmax = 0.29 e Å−3 |
2575 reflections | Δρmin = −0.41 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 | ||
Zn1 | 0.13542 (3) | 0.67259 (2) | 0.95778 (2) | 0.01747 (8) | |
N1 | 0.5348 (2) | 0.80601 (17) | 1.37504 (16) | 0.0170 (3) | |
N2 | 0.5678 (2) | 0.94439 (18) | 1.31816 (18) | 0.0240 (3) | |
N3 | 0.3418 (2) | 0.76120 (17) | 1.15051 (16) | 0.0171 (3) | |
N4 | 0.8152 (2) | 0.61031 (17) | 1.41296 (16) | 0.0173 (3) | |
N5 | 0.7474 (2) | 0.46692 (18) | 1.44963 (18) | 0.0218 (3) | |
N6 | 0.8153 (2) | 0.43662 (17) | 1.22871 (16) | 0.0182 (3) | |
N7 | 0.1502 (3) | 0.8848 (2) | 0.8806 (2) | 0.0299 (4) | |
N8 | 0.0641 (2) | 0.97580 (17) | 0.82908 (17) | 0.0207 (3) | |
N9 | −0.0158 (3) | 1.0664 (2) | 0.7738 (2) | 0.0358 (4) | |
N10 | −0.1289 (2) | 0.58864 (18) | 0.95056 (19) | 0.0218 (3) | |
N11 | −0.2475 (2) | 0.66411 (18) | 0.93077 (19) | 0.0234 (3) | |
N12 | −0.3654 (3) | 0.7307 (3) | 0.9122 (3) | 0.0521 (6) | |
C1 | 0.4480 (3) | 0.9117 (2) | 1.1833 (2) | 0.0221 (4) | |
H1A | 0.4363 | 0.9863 | 1.1147 | 0.027* | |
C2 | 0.4014 (2) | 0.6990 (2) | 1.2742 (2) | 0.0189 (3) | |
H2A | 0.3557 | 0.5938 | 1.2885 | 0.023* | |
C3 | 0.7502 (2) | 0.3663 (2) | 1.3352 (2) | 0.0198 (3) | |
H3A | 0.7103 | 0.2548 | 1.3277 | 0.024* | |
C4 | 0.8546 (2) | 0.5909 (2) | 1.2821 (2) | 0.0189 (3) | |
H4A | 0.9031 | 0.6739 | 1.2339 | 0.023* | |
C5 | 0.6499 (3) | 0.7874 (2) | 1.52177 (19) | 0.0203 (4) | |
H5A | 0.5843 | 0.6973 | 1.5594 | 0.024* | |
H5B | 0.6701 | 0.8843 | 1.5948 | 0.024* | |
C6 | 0.8366 (2) | 0.7579 (2) | 1.5123 (2) | 0.0206 (4) | |
H6A | 0.9016 | 0.8475 | 1.4737 | 0.025* | |
H6B | 0.9141 | 0.7528 | 1.6148 | 0.025* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Zn1 | 0.01774 (12) | 0.01953 (12) | 0.01378 (11) | 0.00251 (8) | 0.00409 (8) | 0.00027 (7) |
N1 | 0.0183 (7) | 0.0165 (7) | 0.0159 (7) | 0.0047 (6) | 0.0041 (6) | 0.0009 (5) |
N2 | 0.0281 (8) | 0.0168 (7) | 0.0231 (8) | 0.0014 (6) | 0.0032 (7) | 0.0029 (6) |
N3 | 0.0179 (7) | 0.0152 (6) | 0.0174 (7) | 0.0028 (5) | 0.0046 (6) | 0.0019 (5) |
N4 | 0.0181 (7) | 0.0170 (7) | 0.0160 (7) | 0.0037 (6) | 0.0039 (6) | 0.0014 (5) |
N5 | 0.0265 (8) | 0.0201 (7) | 0.0211 (8) | 0.0046 (6) | 0.0110 (6) | 0.0040 (6) |
N6 | 0.0203 (7) | 0.0183 (7) | 0.0169 (7) | 0.0042 (6) | 0.0071 (6) | 0.0023 (6) |
N7 | 0.0354 (10) | 0.0238 (8) | 0.0289 (9) | 0.0064 (7) | 0.0042 (7) | 0.0097 (7) |
N8 | 0.0255 (8) | 0.0149 (7) | 0.0183 (7) | −0.0014 (6) | 0.0055 (6) | −0.0007 (6) |
N9 | 0.0336 (10) | 0.0207 (8) | 0.0495 (12) | 0.0068 (7) | 0.0042 (9) | 0.0082 (8) |
N10 | 0.0223 (8) | 0.0164 (7) | 0.0267 (8) | 0.0026 (6) | 0.0087 (6) | 0.0017 (6) |
N11 | 0.0190 (8) | 0.0209 (7) | 0.0258 (8) | 0.0004 (6) | 0.0022 (6) | 0.0015 (6) |
N12 | 0.0274 (10) | 0.0410 (11) | 0.0824 (18) | 0.0146 (9) | 0.0012 (11) | 0.0086 (11) |
C1 | 0.0266 (9) | 0.0162 (8) | 0.0206 (9) | 0.0021 (7) | 0.0033 (7) | 0.0039 (7) |
C2 | 0.0212 (8) | 0.0154 (8) | 0.0190 (8) | 0.0031 (7) | 0.0048 (7) | 0.0025 (6) |
C3 | 0.0216 (9) | 0.0186 (8) | 0.0205 (8) | 0.0035 (7) | 0.0086 (7) | 0.0032 (7) |
C4 | 0.0215 (9) | 0.0189 (8) | 0.0167 (8) | 0.0039 (7) | 0.0062 (7) | 0.0029 (6) |
C5 | 0.0236 (9) | 0.0245 (9) | 0.0126 (8) | 0.0085 (7) | 0.0032 (7) | −0.0001 (6) |
C6 | 0.0201 (8) | 0.0201 (8) | 0.0180 (8) | 0.0048 (7) | 0.0013 (7) | −0.0038 (7) |
Zn1—N3 | 2.0222 (15) | N6—C3 | 1.360 (2) |
Zn1—N7 | 2.0344 (18) | N6—Zn1i | 2.0476 (15) |
Zn1—N6i | 2.0476 (15) | N7—N8 | 1.179 (2) |
Zn1—N10 | 1.9964 (17) | N8—N9 | 1.162 (2) |
Zn1—N10ii | 2.4943 (17) | N10—N11 | 1.203 (2) |
N1—C2 | 1.327 (2) | N10—Zn1ii | 2.4943 (17) |
N1—N2 | 1.364 (2) | N11—N12 | 1.145 (3) |
N1—C5 | 1.457 (2) | C1—H1A | 0.9500 |
N2—C1 | 1.312 (2) | C2—H2A | 0.9500 |
N3—C2 | 1.324 (2) | C3—H3A | 0.9500 |
N3—C1 | 1.363 (2) | C4—H4A | 0.9500 |
N4—C4 | 1.327 (2) | C5—C6 | 1.520 (3) |
N4—N5 | 1.365 (2) | C5—H5A | 0.9900 |
N4—C6 | 1.462 (2) | C5—H5B | 0.9900 |
N5—C3 | 1.316 (2) | C6—H6A | 0.9900 |
N6—C4 | 1.333 (2) | C6—H6B | 0.9900 |
N3—Zn1—N7 | 93.69 (7) | N11—N10—Zn1ii | 128.71 (13) |
N3—Zn1—N6i | 121.68 (6) | Zn1—N10—Zn1ii | 105.32 (7) |
N3—Zn1—N10ii | 85.78 (6) | N12—N11—N10 | 177.3 (2) |
N6i—Zn1—N10ii | 85.28 (6) | N2—C1—N3 | 113.97 (16) |
N7—Zn1—N6i | 93.08 (7) | N2—C1—H1A | 123.0 |
N7—Zn1—N10ii | 177.67 (6) | N3—C1—H1A | 123.0 |
N10—Zn1—N3 | 124.15 (7) | N3—C2—N1 | 109.64 (16) |
N10—Zn1—N6i | 108.40 (6) | N3—C2—H2A | 125.2 |
N10—Zn1—N7 | 107.44 (7) | N1—C2—H2A | 125.2 |
N10—Zn1—N10ii | 74.68 (7) | N5—C3—N6 | 113.90 (16) |
C2—N1—N2 | 110.20 (15) | N5—C3—H3A | 123.1 |
C2—N1—C5 | 128.95 (16) | N6—C3—H3A | 123.1 |
N2—N1—C5 | 120.62 (15) | N4—C4—N6 | 109.27 (15) |
C1—N2—N1 | 102.65 (15) | N4—C4—H4A | 125.4 |
C2—N3—C1 | 103.54 (15) | N6—C4—H4A | 125.4 |
C2—N3—Zn1 | 131.43 (12) | N1—C5—C6 | 111.49 (14) |
C1—N3—Zn1 | 124.94 (12) | N1—C5—H5A | 109.3 |
C4—N4—N5 | 110.40 (14) | C6—C5—H5A | 109.3 |
C4—N4—C6 | 128.55 (16) | N1—C5—H5B | 109.3 |
N5—N4—C6 | 121.05 (14) | C6—C5—H5B | 109.3 |
C3—N5—N4 | 102.73 (14) | H5A—C5—H5B | 108.0 |
C4—N6—C3 | 103.71 (14) | N4—C6—C5 | 111.59 (15) |
C4—N6—Zn1i | 128.64 (12) | N4—C6—H6A | 109.3 |
C3—N6—Zn1i | 127.39 (12) | C5—C6—H6A | 109.3 |
N8—N7—Zn1 | 145.03 (16) | N4—C6—H6B | 109.3 |
N9—N8—N7 | 176.8 (2) | C5—C6—H6B | 109.3 |
N11—N10—Zn1 | 124.83 (13) | H6A—C6—H6B | 108.0 |
C2—N1—N2—C1 | 0.5 (2) | N10ii—Zn1—N10—Zn1ii | 0.0 |
C5—N1—N2—C1 | 175.53 (15) | N1—N2—C1—N3 | −0.4 (2) |
N10—Zn1—N3—C2 | 55.90 (18) | C2—N3—C1—N2 | 0.1 (2) |
N7—Zn1—N3—C2 | 169.90 (17) | Zn1—N3—C1—N2 | 177.08 (13) |
N6i—Zn1—N3—C2 | −94.18 (17) | C1—N3—C2—N1 | 0.2 (2) |
N10ii—Zn1—N3—C2 | −12.37 (16) | Zn1—N3—C2—N1 | −176.47 (12) |
N10—Zn1—N3—C1 | −120.15 (15) | N2—N1—C2—N3 | −0.5 (2) |
N7—Zn1—N3—C1 | −6.15 (16) | C5—N1—C2—N3 | −174.96 (16) |
N6i—Zn1—N3—C1 | 89.76 (16) | N4—N5—C3—N6 | 0.0 (2) |
N10ii—Zn1—N3—C1 | 171.58 (15) | C4—N6—C3—N5 | −0.1 (2) |
C4—N4—N5—C3 | 0.07 (19) | Zn1i—N6—C3—N5 | 174.41 (12) |
C6—N4—N5—C3 | −179.75 (15) | N5—N4—C4—N6 | −0.1 (2) |
N3—Zn1—N7—N8 | −130.9 (3) | C6—N4—C4—N6 | 179.66 (16) |
N6i—Zn1—N7—N8 | 107.0 (3) | C3—N6—C4—N4 | 0.1 (2) |
N3—Zn1—N10—N11 | 94.82 (17) | Zn1i—N6—C4—N4 | −174.27 (11) |
N7—Zn1—N10—N11 | −12.31 (18) | C2—N1—C5—C6 | 97.0 (2) |
N6i—Zn1—N10—N11 | −111.75 (16) | N2—N1—C5—C6 | −77.0 (2) |
N10ii—Zn1—N10—N11 | 168.7 (2) | C4—N4—C6—C5 | 114.3 (2) |
N3—Zn1—N10—Zn1ii | −73.86 (8) | N5—N4—C6—C5 | −65.9 (2) |
N7—Zn1—N10—Zn1ii | 179.00 (6) | N1—C5—C6—N4 | −62.6 (2) |
N6i—Zn1—N10—Zn1ii | 79.57 (7) |
Symmetry codes: (i) −x+1, −y+1, −z+2; (ii) −x, −y+1, −z+2. |
Experimental details
Crystal data | |
Chemical formula | [Zn(N3)2(C6H8N6)] |
Mr | 313.61 |
Crystal system, space group | Triclinic, P1 |
Temperature (K) | 193 |
a, b, c (Å) | 7.646 (3), 8.690 (3), 9.266 (3) |
α, β, γ (°) | 95.430 (5), 105.054 (6), 100.884 (5) |
V (Å3) | 577.1 (3) |
Z | 2 |
Radiation type | Mo Kα |
µ (mm−1) | 2.14 |
Crystal size (mm) | 0.50 × 0.35 × 0.21 |
Data collection | |
Diffractometer | Rigaku Mercury CCD diffractometer |
Absorption correction | Multi-scan (North et al., 1968) |
Tmin, Tmax | 0.412, 0.638 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 6341, 2575, 2488 |
Rint | 0.023 |
(sin θ/λ)max (Å−1) | 0.649 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.025, 0.063, 1.06 |
No. of reflections | 2575 |
No. of parameters | 172 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.29, −0.41 |
Computer programs: CrystalClear (Rigaku, 2000), CrystalClear, SHELXS97 (Sheldrick, 1997), SHELXL97 (Sheldrick, 1997), SHELXTL (Bruker, 1998), SHELXTL & DIAMOND (Brandenburg, 2000).
Zn1—N3 | 2.0222 (15) | Zn1—N10 | 1.9964 (17) |
Zn1—N7 | 2.0344 (18) | Zn1—N10ii | 2.4943 (17) |
Zn1—N6i | 2.0476 (15) | ||
N3—Zn1—N7 | 93.69 (7) | N10—Zn1—N3 | 124.15 (7) |
N3—Zn1—N6i | 121.68 (6) | N10—Zn1—N6i | 108.40 (6) |
N3—Zn1—N10ii | 85.78 (6) | N10—Zn1—N7 | 107.44 (7) |
N6i—Zn1—N10ii | 85.28 (6) | N10—Zn1—N10ii | 74.68 (7) |
N7—Zn1—N6i | 93.08 (7) | Zn1—N10—Zn1ii | 105.32 (7) |
N7—Zn1—N10ii | 177.67 (6) |
Symmetry codes: (i) −x+1, −y+1, −z+2; (ii) −x, −y+1, −z+2. |
Interest in the crystal engineering of coordinated frameworks stems not only from their potential applications as zeolite-like materials in molecular selection, ion exchange and catalysis but also from their intriguing variety of architectures and topologies (Robson et al., 1992). The design of coordination polymers is highly influenced by several factors, such as the metal-coordination preference, the structural characteristics of the polydentate organic ligand, the metal–ligand ratio, the solvent system and the counter-ion (Batten & Murray, 2003; Riggio et al., 2001). The most widely used ligands are rigid rod-like organic building blocks, such as 4,4'-bipyridine (Fujita et al., 1994) and 4,4'-azobispyridine (Li et al., 2001). Relatively few studies of flexible ligands have been reported, but bis(1,2,4-triazole-1-yl)ethane (Li et al., 1999a, 1999b, 2003) is an excellent flexible ligand candidate for further research.
The pseudohalide azide has been demonstrated to be an extremely versatile ligand. It may provide end-to-end (EE or 1,3), end-on (EO or 1,1) or terminal coordination modes. Thus a large number of azide-bridged polymers have been synthesized and magneto-structurally characterized (Ribas et al., 1999). However, azide-bridged Zn polymers are relatively rare (Krischner et al., 1986; Pan et al., 1999; Chen & Chen, 2002). In the present work, we report the preparation and crystal structure of [Zn(bte)(N3)2]n, (I), which exhibits a novel one-dimensional chain with both four-membered Zn(µ-1,1-N3)2Zn and 18-membered Zn(gauche-bte)2Zn rings.
The molecular structure of (I) is shown in Fig. 1, and Table 1 gives selected structural parameters. Each Zn atom is pentacoordinated in a distorted trigonal-bipyramidal coordination environment. The trigonal base plane is defined by two N atoms [N3 and N6i; symmetry code: (i) 1 − x, 1 − y, 2 − z] from two bridging bte ligands and one N atom (N10) from an azide ligand. The Zn—Nbte bond lengths are shorter than those found in [Zn(dca)2(bte)2]n (Li et al., 2003). Two azide N atoms [N7 and N10ii; symmetry code: (ii) −x, 1 − y, 2 − z] occupy the axial positions. Atoms Zn1, N7 and N10ii deviate from the trigonal base plane by 0.2809 (9), 2.2874 (20) and −2.1934 (24) Å, respectively. One azide ligand is monodentate; the other acts as a bridging ligand linking two Zn atoms in an end-on (EO or 1,1) coordination mode [Zn1—N10—Zn1ii = 105.32 (7)°], generating a four-membered Zn(µ-1,1-N3)2Zn ring, with an intraring Zn···Zn distance of 3.5830 (9) Å.
Compound (I) develops into an infinite one-dimensional chain extending along the a axis and constructed from alternate interconnection of four-membered Zn(µ-1,1-N3)2Zn and 18-membered Zn(gauche-bte)2Zn rings (Fig. 2). The bte ligands exhibit a gauche conformation. The two triazole ring planes, viz. C1/C2/N1–N3 and C3/C4/N4–N6, are planar, with r.m.s. deviations of 0.0019 (11) and 0.0006 (10) Å, respectively. The dihedral angle between these two triazole ring planes is 51.65 (6)°. The bte ligand is twisted, the N1—C5—C6—N4 torsion angle being 62.62 (20)°.
There are four potentially coordinating N atoms in the bte ligand, but only two, at the 4-positions of the triazole rings, coordinate to Zn atoms. Two bte ligands are thus held together by two Zn atoms, forming a Zn(gauche-bte)2Zn ring around a centre of inversion, similar to that found in [Zn(dca)2(bte)2]n (Li et al., 2003). The Zn···Zn separation across the 18-membered ring is 6.7220 (18) Å, which is obviously shorter than the 8.369 (4) Å separation in [Zn(dca)2(bte)2]n. There are weak H···N interactions between the azide N atoms and alkane (triazole) H atoms of neighboring chains [N8···H6B—C6iii, 2.503 Å, and N9···H4A—C4iv, 2.274 Å; symmetry codes: (iii) −1 + x, y, −1 + z; (iv) 1 − x, 2 − y, 2 − z] linking adjacent chains in the crystal.
One example of an azide-bridged Zn polymer is [Zn(N3)2(4,4'-bipy)] (Pan et al., 1999 & Martin et al., 2001), in which the Zn/azide chain is an interesting combination of bridging types, incorporating four-membered ZnN2Zn rings, in which the azides bridge through one terminal atom, and six-membered rings, in which one of the azides coordinates to a pair of Zn atoms in an end-on fashion. Further examples are [Zn(N3)2L] (L is 2-methylpyridine, 3-methylpyridine, 4-methylpyridine, and 2,4-, 3,4- and 3,5-dimethylpyridine) (Mautner et al., 1987, 1988a, 1988b, 1992), in which each Zn atom is surrounded by four N atoms from different azide groups and one N atom from the pyridine in a distorted trigonal-bipyramidal fashion. The ZnN5 polyhedra share common edges, thus forming chains. To our knowledge, a one-dimensional chain constructed from alternate interconnection of four-membered and 18-membered rings is unusual. The structure of (I) is a successful example of synthesis of a novel polymer using the flexible bis(1,2,4-triazol-1-yl)alkane ligand.