Acta Cryst. (2009). E65, m42-m43 [ doi:10.1107/S1600536808040634 ]
-sulfato-bis[diaqua(1H-imidazo[4,5-f][1,10]phenanthroline)nickel(II)] dihydrateIn the title compound, [Ni2(SO4)2(C13H8N4)2(H2O)4]·2H2O, the complete dimeric complex is generated by an inversion center. The NiII atoms are octahedrally coordinated by two N atoms from one 1H-imidazo[4,5-f][1,10]phenanthroline (IP) ligand and two O atoms from two adjacent sulfate ions forming the equatorial plane, with two coordinated water molecules in the axial sites. Both of the sulfate ions act as bidentate-bridging ligands connecting the two NiII ions, thus generating a binuclear complex. In the crystal structure, O-H
O and O-H
N hydrogen bonds involving the coordinated and uncoordinated water molecules and N-H
O links lead to the formation of a two-dimensional sheet structure developing parallel to (010). Weak
-
stacking interactions [centroid-centroid separation = 3.613 (2) Å] between the IP ligands also occur.
IP (0.031 g, 0.18 mmol) and NiSO4 (0.28 g, 0.11 mmol) were added to acetonitrile (15 ml), the mixture was heated for ten hours under reflux conditions. The resultant solution was then filtered to give a pure solution which was infiltrated by diethyl ether freely in a closed vessel: three weeks later, green blocks of (I) were collected.
All H atoms attached to C atoms, and N atoms were fixed geometrically and treated as riding with C—H distances of 0.93Å (pyridine ring), 0.86 Å (amine group), with UisoH = 1.2Ueq(C). H atoms of water molecule were located in difference Fourier maps and included in the subsequent refinement using restraints [O—H = 0.82 (1)Å and H···H = 1.38 (2) Å]. In the last stage of refinement, they were treated as riding on their parent O atom with O—H = 0.80Å.
Data collection: APEX2 (Bruker, 2004); cell refinement: SAINT (Bruker, 2004); data reduction: SAINT (Bruker, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).
| [Ni2(SO4)2(C13H8N4)2(H2O)4]·2H2O | F(000) = 880 |
| Mr = 858.10 | Dx = 1.839 Mg m−3 |
| Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
| Hall symbol: -P 2ybc | Cell parameters from 2887 reflections |
| a = 10.296 (2) Å | θ = 2.5–25.5° |
| b = 9.0560 (18) Å | µ = 1.44 mm−1 |
| c = 16.836 (3) Å | T = 298 K |
| β = 99.108 (3)° | Block, green |
| V = 1550.0 (5) Å3 | 0.28 × 0.20 × 0.13 mm |
| Z = 2 |
| Bruker APEXII CCD diffractometer | 2887 independent reflections |
| Radiation source: fine-focus sealed tube | 2085 reflections with I > 2σ(I) |
| graphite | Rint = 0.040 |
| φ and ω scans | θmax = 25.5°, θmin = 2.5° |
| Absorption correction: multi-scan (SADABS; Bruker, 2004) | h = −12→11 |
| Tmin = 0.689, Tmax = 0.835 | k = −8→10 |
| 7756 measured reflections | l = −20→20 |
| 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)] = 0.043 | Hydrogen site location: inferred from neighbouring sites |
| wR(F2) = 0.146 | H-atom parameters constrained |
| S = 0.81 | w = 1/[σ2(Fo2) + (0.127P)2] where P = (Fo2 + 2Fc2)/3 |
| 2887 reflections | (Δ/σ)max < 0.001 |
| 236 parameters | Δρmax = 0.47 e Å−3 |
| 0 restraints | Δρmin = −0.40 e Å−3 |
| [Ni2(SO4)2(C13H8N4)2(H2O)4]·2H2O | V = 1550.0 (5) Å3 |
| Mr = 858.10 | Z = 2 |
| Monoclinic, P21/c | Mo Kα radiation |
| a = 10.296 (2) Å | µ = 1.44 mm−1 |
| b = 9.0560 (18) Å | T = 298 K |
| c = 16.836 (3) Å | 0.28 × 0.20 × 0.13 mm |
| β = 99.108 (3)° |
| Bruker APEXII CCD diffractometer | 2887 independent reflections |
| Absorption correction: multi-scan (SADABS; Bruker, 2004) | 2085 reflections with I > 2σ(I) |
| Tmin = 0.689, Tmax = 0.835 | Rint = 0.040 |
| 7756 measured reflections | θmax = 25.5° |
| R[F2 > 2σ(F2)] = 0.043 | H-atom parameters constrained |
| wR(F2) = 0.146 | Δρmax = 0.47 e Å−3 |
| S = 0.81 | Δρmin = −0.40 e Å−3 |
| 2887 reflections | Absolute structure: ? |
| 236 parameters | Flack parameter: ? |
| 0 restraints | Rogers parameter: ? |
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 | ||
| Ni1 | 0.18902 (5) | 0.68064 (6) | 0.04131 (3) | 0.0299 (2) | |
| S1 | −0.03201 (9) | 0.60119 (10) | −0.11230 (5) | 0.0263 (3) | |
| N1 | 0.2570 (3) | 0.9021 (4) | 0.03289 (18) | 0.0266 (7) | |
| N2 | 0.3746 (3) | 0.6769 (3) | 0.11665 (19) | 0.0275 (7) | |
| N3 | 0.6436 (3) | 1.2065 (4) | 0.1392 (2) | 0.0338 (8) | |
| N4 | 0.7470 (3) | 1.0131 (4) | 0.20327 (19) | 0.0340 (8) | |
| H4A | 0.8077 | 0.9627 | 0.2321 | 0.034 (12)* | |
| O1W | 0.0747 (3) | 0.7638 (4) | 0.12140 (18) | 0.0487 (9) | |
| H1WA | 0.0783 | 0.8400 | 0.1457 | 0.058* | |
| H1WB | 0.0340 | 0.6894 | 0.1248 | 0.058* | |
| O2W | 0.2961 (3) | 0.5649 (3) | −0.03940 (15) | 0.0342 (7) | |
| H2WA | 0.3137 | 0.6304 | −0.0678 | 0.041* | |
| H2WB | 0.2281 | 0.5421 | −0.0666 | 0.041* | |
| O2 | −0.0906 (3) | 0.6771 (3) | −0.18632 (17) | 0.0401 (8) | |
| O4 | 0.0613 (3) | 0.4873 (3) | −0.13353 (15) | 0.0311 (6) | |
| O1 | 0.0382 (2) | 0.7092 (3) | −0.05661 (16) | 0.0300 (6) | |
| O3W | 0.0861 (4) | 0.0146 (4) | 0.20094 (19) | 0.0661 (11) | |
| H3WB | 0.0873 | 0.1025 | 0.1963 | 0.079* | |
| H3WA | 0.0790 | 0.0137 | 0.2476 | 0.079* | |
| C1 | 0.1913 (4) | 1.0142 (5) | −0.0056 (2) | 0.0314 (9) | |
| H1A | 0.1083 | 0.9961 | −0.0347 | 0.038* | |
| C2 | 0.2408 (4) | 1.1571 (5) | −0.0042 (2) | 0.0339 (10) | |
| H2A | 0.1915 | 1.2325 | −0.0318 | 0.041* | |
| C3 | 0.3637 (4) | 1.1857 (4) | 0.0385 (2) | 0.0308 (9) | |
| H3A | 0.3989 | 1.2804 | 0.0395 | 0.037* | |
| C4 | 0.4353 (3) | 1.0702 (4) | 0.0806 (2) | 0.0263 (9) | |
| C5 | 0.3759 (3) | 0.9290 (4) | 0.0770 (2) | 0.0231 (8) | |
| C6 | 0.4416 (4) | 0.8062 (4) | 0.1208 (2) | 0.0250 (8) | |
| C7 | 0.4319 (4) | 0.5593 (5) | 0.1541 (2) | 0.0337 (9) | |
| H7A | 0.3860 | 0.4705 | 0.1505 | 0.040* | |
| C8 | 0.5586 (4) | 0.5636 (5) | 0.1988 (2) | 0.0358 (10) | |
| H8A | 0.5960 | 0.4790 | 0.2241 | 0.043* | |
| C9 | 0.6267 (4) | 0.6942 (4) | 0.2048 (2) | 0.0323 (10) | |
| H9A | 0.7107 | 0.6993 | 0.2347 | 0.039* | |
| C10 | 0.5692 (4) | 0.8195 (4) | 0.1657 (2) | 0.0250 (8) | |
| C11 | 0.6261 (4) | 0.9622 (5) | 0.1659 (2) | 0.0300 (9) | |
| C12 | 0.5625 (4) | 1.0813 (4) | 0.1265 (2) | 0.0291 (9) | |
| C13 | 0.7502 (4) | 1.1573 (5) | 0.1853 (3) | 0.0378 (10) | |
| H13A | 0.8218 | 1.2175 | 0.2039 | 0.045* | |
| O3 | −0.1354 (3) | 0.5305 (3) | −0.07522 (17) | 0.0352 (7) |
| U11 | U22 | U33 | U12 | U13 | U23 | |
| Ni1 | 0.0279 (3) | 0.0279 (4) | 0.0327 (3) | −0.0050 (2) | 0.0010 (2) | −0.0018 (2) |
| S1 | 0.0263 (5) | 0.0234 (6) | 0.0273 (5) | −0.0047 (4) | −0.0016 (4) | 0.0013 (4) |
| N1 | 0.0259 (17) | 0.0269 (19) | 0.0260 (16) | −0.0023 (14) | 0.0013 (13) | 0.0010 (14) |
| N2 | 0.0265 (17) | 0.0267 (19) | 0.0294 (17) | −0.0031 (14) | 0.0046 (14) | −0.0015 (14) |
| N3 | 0.033 (2) | 0.033 (2) | 0.0345 (19) | −0.0099 (15) | 0.0029 (16) | −0.0019 (15) |
| N4 | 0.0277 (18) | 0.040 (2) | 0.0310 (17) | −0.0034 (16) | −0.0053 (15) | 0.0003 (16) |
| O1W | 0.061 (2) | 0.0305 (18) | 0.061 (2) | −0.0183 (16) | 0.0311 (18) | −0.0190 (16) |
| O2W | 0.0315 (15) | 0.0345 (17) | 0.0370 (15) | −0.0029 (13) | 0.0061 (13) | −0.0004 (12) |
| O2 | 0.0454 (19) | 0.0349 (18) | 0.0342 (16) | −0.0055 (13) | −0.0118 (14) | 0.0063 (13) |
| O4 | 0.0293 (15) | 0.0253 (15) | 0.0375 (15) | −0.0050 (12) | 0.0021 (12) | −0.0043 (12) |
| O1 | 0.0253 (14) | 0.0252 (15) | 0.0348 (15) | −0.0025 (11) | −0.0096 (12) | −0.0042 (11) |
| O3W | 0.126 (4) | 0.0292 (19) | 0.0479 (19) | −0.015 (2) | 0.028 (2) | −0.0107 (16) |
| C1 | 0.023 (2) | 0.033 (2) | 0.036 (2) | −0.0010 (17) | −0.0009 (16) | 0.0032 (18) |
| C2 | 0.034 (2) | 0.031 (2) | 0.034 (2) | 0.0067 (18) | −0.0012 (18) | 0.0047 (18) |
| C3 | 0.036 (2) | 0.019 (2) | 0.036 (2) | −0.0032 (17) | 0.0020 (18) | −0.0029 (17) |
| C4 | 0.025 (2) | 0.028 (2) | 0.0251 (18) | −0.0012 (16) | 0.0022 (16) | −0.0029 (16) |
| C5 | 0.0232 (19) | 0.021 (2) | 0.0240 (18) | −0.0031 (15) | 0.0006 (15) | 0.0002 (15) |
| C6 | 0.026 (2) | 0.025 (2) | 0.0239 (19) | −0.0050 (16) | 0.0027 (16) | −0.0018 (15) |
| C7 | 0.038 (2) | 0.027 (2) | 0.035 (2) | −0.0067 (18) | 0.0029 (18) | 0.0014 (18) |
| C8 | 0.039 (2) | 0.029 (2) | 0.038 (2) | 0.0085 (19) | 0.0021 (19) | 0.0065 (18) |
| C9 | 0.024 (2) | 0.038 (3) | 0.032 (2) | −0.0001 (18) | −0.0031 (17) | −0.0009 (18) |
| C10 | 0.027 (2) | 0.025 (2) | 0.0236 (18) | −0.0011 (16) | 0.0045 (16) | −0.0009 (15) |
| C11 | 0.024 (2) | 0.039 (2) | 0.0252 (19) | −0.0072 (18) | −0.0023 (16) | −0.0030 (18) |
| C12 | 0.031 (2) | 0.030 (2) | 0.0265 (19) | −0.0052 (17) | 0.0061 (16) | −0.0013 (17) |
| C13 | 0.038 (3) | 0.035 (3) | 0.038 (2) | −0.019 (2) | −0.001 (2) | −0.0038 (19) |
| O3 | 0.0311 (15) | 0.0242 (15) | 0.0521 (17) | −0.0034 (12) | 0.0116 (13) | 0.0031 (13) |
| Ni1—O1W | 2.067 (3) | O3W—H3WB | 0.8000 |
| Ni1—O3i | 2.095 (3) | O3W—H3WA | 0.8000 |
| Ni1—O1 | 2.094 (3) | C1—C2 | 1.390 (6) |
| Ni1—N2 | 2.120 (3) | C1—H1A | 0.9300 |
| Ni1—N1 | 2.136 (3) | C2—C3 | 1.378 (6) |
| Ni1—O2W | 2.152 (3) | C2—H2A | 0.9300 |
| S1—O1 | 1.464 (3) | C3—C4 | 1.405 (5) |
| S1—O3 | 1.464 (3) | C3—H3A | 0.9300 |
| S1—O2 | 1.467 (3) | C4—C5 | 1.414 (5) |
| S1—O4 | 1.491 (3) | C4—C12 | 1.415 (5) |
| N1—C1 | 1.330 (5) | C5—C6 | 1.442 (5) |
| N1—C5 | 1.349 (5) | C6—C10 | 1.413 (5) |
| N2—C7 | 1.327 (5) | C7—C8 | 1.400 (6) |
| N2—C6 | 1.355 (5) | C7—H7A | 0.9300 |
| N3—C13 | 1.317 (5) | C8—C9 | 1.371 (6) |
| N3—C12 | 1.405 (5) | C8—H8A | 0.9300 |
| N4—C13 | 1.341 (5) | C9—C10 | 1.396 (5) |
| N4—C11 | 1.382 (5) | C9—H9A | 0.9300 |
| N4—H4A | 0.8600 | C10—C11 | 1.419 (5) |
| O1W—H1WA | 0.8000 | C11—C12 | 1.376 (6) |
| O1W—H1WB | 0.8000 | C13—H13A | 0.9300 |
| O2W—H2WA | 0.8000 | O3—Ni1i | 2.095 (3) |
| O2W—H2WB | 0.8000 | ||
| O1W—Ni1—O3i | 87.30 (12) | N1—C1—H1A | 118.5 |
| O1W—Ni1—O1 | 92.33 (12) | C2—C1—H1A | 118.5 |
| O3i—Ni1—O1 | 97.62 (11) | C3—C2—C1 | 119.2 (4) |
| O1W—Ni1—N2 | 99.67 (13) | C3—C2—H2A | 120.4 |
| O3i—Ni1—N2 | 94.22 (11) | C1—C2—H2A | 120.4 |
| O1—Ni1—N2 | 163.51 (11) | C2—C3—C4 | 119.2 (4) |
| O1W—Ni1—N1 | 85.86 (12) | C2—C3—H3A | 120.4 |
| O3i—Ni1—N1 | 168.08 (11) | C4—C3—H3A | 120.4 |
| O1—Ni1—N1 | 92.40 (11) | C3—C4—C5 | 117.6 (3) |
| N2—Ni1—N1 | 77.35 (12) | C3—C4—C12 | 126.1 (4) |
| O1W—Ni1—O2W | 172.06 (12) | C5—C4—C12 | 116.4 (3) |
| O3i—Ni1—O2W | 84.89 (10) | N1—C5—C4 | 122.4 (3) |
| O1—Ni1—O2W | 87.31 (11) | N1—C5—C6 | 117.0 (3) |
| N2—Ni1—O2W | 82.35 (11) | C4—C5—C6 | 120.7 (3) |
| N1—Ni1—O2W | 102.08 (11) | N2—C6—C10 | 121.6 (3) |
| O1—S1—O3 | 109.72 (16) | N2—C6—C5 | 116.5 (3) |
| O1—S1—O2 | 109.01 (16) | C10—C6—C5 | 121.9 (3) |
| O3—S1—O2 | 109.77 (17) | N2—C7—C8 | 122.7 (4) |
| O1—S1—O4 | 110.14 (15) | N2—C7—H7A | 118.7 |
| O3—S1—O4 | 109.85 (16) | C8—C7—H7A | 118.7 |
| O2—S1—O4 | 108.32 (17) | C9—C8—C7 | 119.1 (4) |
| C1—N1—C5 | 118.5 (3) | C9—C8—H8A | 120.5 |
| C1—N1—Ni1 | 127.0 (3) | C7—C8—H8A | 120.5 |
| C5—N1—Ni1 | 114.3 (2) | C8—C9—C10 | 119.5 (4) |
| C7—N2—C6 | 119.0 (3) | C8—C9—H9A | 120.2 |
| C7—N2—Ni1 | 126.0 (3) | C10—C9—H9A | 120.2 |
| C6—N2—Ni1 | 114.9 (3) | C9—C10—C11 | 126.5 (4) |
| C13—N3—C12 | 103.7 (3) | C9—C10—C6 | 118.2 (3) |
| C13—N4—C11 | 106.0 (3) | C11—C10—C6 | 115.3 (3) |
| C13—N4—H4A | 127.0 | N4—C11—C12 | 106.5 (4) |
| C11—N4—H4A | 127.0 | N4—C11—C10 | 130.3 (4) |
| Ni1—O1W—H1WA | 131.4 | C12—C11—C10 | 123.2 (3) |
| Ni1—O1W—H1WB | 95.7 | C11—C12—N3 | 109.4 (3) |
| H1WA—O1W—H1WB | 132.3 | C11—C12—C4 | 122.4 (4) |
| Ni1—O2W—H2WA | 101.7 | N3—C12—C4 | 128.1 (4) |
| Ni1—O2W—H2WB | 89.9 | N3—C13—N4 | 114.4 (4) |
| H2WA—O2W—H2WB | 96.3 | N3—C13—H13A | 122.8 |
| S1—O1—Ni1 | 130.62 (17) | N4—C13—H13A | 122.8 |
| H3WB—O3W—H3WA | 96.4 | S1—O3—Ni1i | 139.12 (17) |
| N1—C1—C2 | 123.1 (4) |
| Symmetry codes: (i) −x, −y+1, −z. |
| D—H···A | D—H | H···A | D···A | D—H···A |
| N4—H4A···O2ii | 0.86 | 2.03 | 2.870 (5) | 165 |
| O1W—H1WA···O3Wiii | 0.80 | 1.83 | 2.630 (4) | 180 |
| O1W—H1WB···O4i | 0.80 | 1.89 | 2.695 (4) | 180 |
| O1W—H1WB···O3i | 0.80 | 2.46 | 2.873 (4) | 114 |
| O2W—H2WA···N3iv | 0.80 | 2.00 | 2.797 (4) | 179 |
| O3W—H3WB···O2i | 0.80 | 2.00 | 2.803 (4) | 179 |
| O3W—H3WA···O4v | 0.80 | 2.04 | 2.839 (4) | 180 |
| O2W—H2WB···O4 | 0.80 | 1.96 | 2.764 (4) | 180 |
| O2W—H2WB···O1 | 0.80 | 2.50 | 2.932 (4) | 115 |
| Symmetry codes: (ii) x+1, −y+3/2, z+1/2; (iii) x, y+1, z; (i) −x, −y+1, −z; (iv) −x+1, −y+2, −z; (v) x, −y+1/2, z+1/2. |
| Ni1—O1W | 2.067 (3) | Ni1—N2 | 2.120 (3) |
| Ni1—O3i | 2.095 (3) | Ni1—N1 | 2.136 (3) |
| Ni1—O1 | 2.094 (3) | Ni1—O2W | 2.152 (3) |
| Symmetry codes: (i) −x, −y+1, −z. |
| D—H···A | D—H | H···A | D···A | D—H···A |
| N4—H4A···O2ii | 0.86 | 2.03 | 2.870 (5) | 165 |
| O1W—H1WA···O3Wiii | 0.80 | 1.83 | 2.630 (4) | 180 |
| O1W—H1WB···O4i | 0.80 | 1.89 | 2.695 (4) | 180 |
| O1W—H1WB···O3i | 0.80 | 2.46 | 2.873 (4) | 114 |
| O2W—H2WA···N3iv | 0.80 | 2.00 | 2.797 (4) | 179 |
| O3W—H3WB···O2i | 0.80 | 2.00 | 2.803 (4) | 179 |
| O3W—H3WA···O4v | 0.80 | 2.04 | 2.839 (4) | 180 |
| O2W—H2WB···O4 | 0.80 | 1.96 | 2.764 (4) | 180 |
| O2W—H2WB···O1 | 0.80 | 2.50 | 2.932 (4) | 115 |
| Symmetry codes: (ii) x+1, −y+3/2, z+1/2; (iii) x, y+1, z; (i) −x, −y+1, −z; (iv) −x+1, −y+2, −z; (v) x, −y+1/2, z+1/2. |
The authors are grateful to SouthWest JiaoTong University for financial support.
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Xu, L., Wang, E.-B. M., Peng, J. & Huang, R.-D. (2003). Inorg. Chem. Commun. 6, 740–743.
Transition-metal complexes with 1,10-phen ligands have shown their employments in catalysis, biochemistry, etc. (Ross, et al., 1999; Xu et al., 2003). 1H-imidazo[4,5-f][1,10]-phenanthroline (IP) is an important derivative of 1,10-phen that has been used to recognize the secondary structure of DNA in Ru(II) complexes (Xiong et al., 1999). Furthermore,the rich electron conjugated rings of IP may be important for providing potential supramolecular recognition sites for π—π aromatic stacking and, via the imidazole moiety, IP can form hydrogen-bonding interactions, thus allowing for the formation of supramolecular assemblies. Herein we report the synthesis and characterization of the title compound, (I).
The center of the dimeric complex is located on an inversion center. Each NiII atom is octahedrally coordinated by two N atoms from one IP ligand and two oxygen atoms from two adjacent sulfate ions forming the equatorial plane, whereas axial positions are occupied by two oxygen atoms of coordinated water molecules (Figure 1). Taking account of these two irregular bond angles [168.06 (11)° for O3—Ni—N1 and 172.06 (12)° for O1W—Ni—O2W], the geometry of copper center is best described as a distorted octahedron (Table 1). The distances of Ni—N and Ni—O bonds are similar to those of related complexes (An et al., 2007; Xu et al., 2003). Both of sulfates taking as bidentated-bridging mode connect NiII ions, generating a binuclear complex. The separation of Ni—Ni distance is 5.16 (6) Å, which is markedly shorter than the corresponding Ni—Ni distance of 6.132 (4)Å in NiII analog (Gu et al., 2004). Each IP molecule only binds to NiII center via two nitrogen atoms from two pyridine rings. The IP ligand does not show any abnormal characteristic, with its four bound rings being basically coplanar. One type of π—π stacking interaction between pyridine and imidazole ring from two adjacent IP ligands. The centroid to centroid distances for the further π—π stacking interaction is 3.613 (2)Å [symmetry code = x, -y, z - 1/2], thus indicating weak π—π stacking interaction (Fig. 2).
Intramolecular hydrogen bonds between coordinated water molecules and oxygen atoms from sulfate ions may contribute to its stability (Table 2). Fruthermore, the linking agent is the extensive hydrogen-bonding network involving all the available water molecules and, together with some N atoms of the organic ligand, resulting in the formation of a two-dimensionnal network (Figure 2). For example, the lattice water molecule (O3W) is hydrogen bonded to the O2 and O4 atoms of two related sulfates groups, so generating a R42(8) motif (Bernstein et al., 1995) (Figure 2).