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Acta Cryst. (2009). E65, m1271    [ doi:10.1107/S1600536809038793 ]

Poly[[triaqua([mu]3-pyridine-2,4,6-tricarboxylato)gadolinium(III)] monohydrate]

H.-S. Wang and W.-Q. Zhang

Abstract top

The title compound, {[Gd(C8H2NO6)(H2O)3]·H2O}n, was obtained in water under hydrothermal conditions. The GdIII ions are nine-coordinated by two O and one N atoms from one pyridine-2,4,6-tricarboxylate ligand, two O atoms from another ligand, one O atom from a third ligand and three coordinated water molecules. Each ligand binds three metal centers. Two-dimensional layers are formed through the Gd-O bonds and the layers are linked by O-H...O hydrogen bonds, forming a three-dimensional network.

Comment top

The preparation and property researching of metal-organic frameworks have attracted widespread interest in recent years due to their potential application in the areas of magnetism, luminescence, adsorption, catalysis and so on (Parker, 2000; Tobisch, 2005; Pan et al., 2003). Multicarboxylic acids containing pyridyl rings were widely used and many 1-D, 2-D and 3-D coordination polymers with novel structures have been reported. Especially, complexes with pyridine-2,4,6-tricarboxylato (H3pta = pyridine-2,4,6-tricarboxylic acid) ligands have been recently reported (Li et al., 2008; Wang et al., 2007; Fu et al., 2008.). The title compound is a new GdIII complex built with pta ligands and prepared under hydrothermal conditions.

As shown in Fig. 1, the local geometry of GdIII ion is a distorted monocapped antitetragonal prism. Each pta ligand connects three GdIII ions with oxgen atoms of the carboxyl groups and the nitrogen atom. There are three coordination water molecules on each GdIII ion. A two-dimentional layer is constructed by the bonding among oxygen atoms and GdIII ions (see Fig. 2). In addition, a lattice water molecule per asymmetric unit is in the crystal structure. Many O—H···O hydrogen bonds are formed between the oxygen atoms of water molecules and the oxygen atoms of caboxyl groups. As a result, the three-dimensional network formed by hydrogen bonds is shown in Fig. 3.

Related literature top

For related crystal structures, see: Gao et al. (2006); Ghosh & Bharadwaj (2005); Wang et al. (2007); Fu et al. (2008); Li et al. (2008). For general background to lanthanide-organic frameworks and their properties, see: Parker (2000); Tobisch (2005); Pan et al. (2003).

Experimental top

A mixture of H3pta (0.0422 g, 0.2 mmol), GdCl3.6H2O (0.0743 g, 0.2 mmol) and deionized water (15 ml) was put in a teflon-lined steel bomb and heated at 453 K for 3 days, then cooled the bomb at a rate of 2 K/hour. The colorless crystals suitable for X-ray diffraction measurements were obtained. Spectroscopic analysis: IR (KBr, ν cm-1): 3606, 3382, 1631, 1608, 1582, 1549, 1445, 1395, 1352, 1277, 1235, 1110, 1025, 950, 931, 818, 791, 740, 664, 623, 587, 543, 479, 435. Elemental analysis, calculated for C8H10GdNO10: C, 21.97; H, 2.30; N, 3.20.%; found: C, 22.18; H, 2.11; N, 3.54%.

Refinement top

All hydrogen atoms bonded to carbon atoms were positioned geometrically and refined as riding, with C—H = 0.95 Å and Uiso(H) = 1.2Ueq(C). The H atoms of water molecules were found from difference Fourier maps and included in the final refinements with a restraint of O—H = 0.75 - 0.85 Å and Uiso(H) = 1.5 Ueq(O).

Computing details top

Data collection: CrystalClear (Rigaku/MSC, 2005); cell refinement: CrystalClear (Rigaku/MSC, 2005); data reduction: CrystalClear (Rigaku/MSC, 2005); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXL97 (Sheldrick, 2008); software used to prepare material for publication: CrystalStructure (Rigaku/MSC, 2005).

Figures top
[Figure 1] Fig. 1. The molecular structure of (I), with atom labels and 30% probability displacement ellipsoids for non-H atoms.
[Figure 2] Fig. 2. The packing of (I), showing the two-dimensional layers formed by Gd—O bonds.
[Figure 3] Fig. 3. View of the three-dimensional network constructed by O—H···O hydrogen bonds (dashed lines). All H atoms were omitted for clarity.
Poly[[triaqua(µ3-pyridine-2,4,6-tricarboxylato)gadolinium(III)] monohydrate] top
Crystal data top
[Gd(C8H2NO6)(H2O)3]·H2OF(000) = 836
Mr = 437.42Dx = 2.503 Mg m−3
Monoclinic, P21/cMo Kα radiation, λ = 0.71070 Å
Hall symbol: -P 2ybcCell parameters from 3775 reflections
a = 11.896 (3) Åθ = 1.7–28.7°
b = 7.2696 (14) ŵ = 5.77 mm−1
c = 13.505 (3) ÅT = 113 K
β = 96.259 (3)°Block, colourless
V = 1160.9 (4) Å30.12 × 0.10 × 0.08 mm
Z = 4
Data collection top
Rigaku Saturn
diffractometer		2776 independent reflections
Radiation source: rotating anode2366 reflections with I > 2σ(I)
confocalRint = 0.038
Detector resolution: 7.31 pixels mm-1θmax = 27.9°, θmin = 1.7°
ω scansh = −15→15
Absorption correction: multi-scan
(REQAB; Jacobson, 1998)		k = −8→9
Tmin = 0.544, Tmax = 0.655l = −17→17
10599 measured reflections
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.021Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.049H atoms treated by a mixture of independent and constrained refinement
S = 1.04 w = 1/[σ2(Fo2) + (0.0242P)2]
where P = (Fo2 + 2Fc2)/3
2776 reflections(Δ/σ)max = 0.001
206 parametersΔρmax = 0.64 e Å−3
8 restraintsΔρmin = −1.29 e Å−3
Crystal data top
[Gd(C8H2NO6)(H2O)3]·H2OV = 1160.9 (4) Å3
Mr = 437.42Z = 4
Monoclinic, P21/cMo Kα radiation
a = 11.896 (3) ŵ = 5.77 mm−1
b = 7.2696 (14) ÅT = 113 K
c = 13.505 (3) Å0.12 × 0.10 × 0.08 mm
β = 96.259 (3)°
Data collection top
Rigaku Saturn
diffractometer		2776 independent reflections
Absorption correction: multi-scan
(REQAB; Jacobson, 1998)		2366 reflections with I > 2σ(I)
Tmin = 0.544, Tmax = 0.655Rint = 0.038
10599 measured reflectionsθmax = 27.9°
Refinement top
R[F2 > 2σ(F2)] = 0.021H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.049Δρmax = 0.64 e Å−3
S = 1.04Δρmin = −1.29 e Å−3
2776 reflectionsAbsolute structure: ?
206 parametersFlack parameter: ?
8 restraintsRogers parameter: ?
Special details top

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 (Å2) top
xyzUiso*/Ueq
Gd10.283337 (12)0.28362 (2)0.703522 (11)0.00496 (6)
O10.46782 (18)0.4287 (3)0.74763 (16)0.0085 (5)
O20.58731 (18)0.5825 (3)0.85710 (16)0.0080 (4)
O30.3449 (2)1.0594 (3)1.05119 (16)0.0101 (5)
O40.25022 (19)0.8881 (3)1.14877 (16)0.0111 (5)
O50.10951 (19)0.3347 (3)0.77338 (17)0.0118 (5)
O60.00718 (19)0.4715 (3)0.88248 (16)0.0105 (5)
O70.3762 (2)0.1238 (3)0.85200 (17)0.0109 (5)
H7A0.425 (3)0.051 (4)0.838 (3)0.016*
H7B0.369 (3)0.110 (5)0.9117 (19)0.016*
O80.1937 (2)−0.0211 (3)0.71872 (18)0.0117 (5)
H8A0.129 (2)−0.034 (5)0.690 (3)0.018*
H8B0.225 (3)−0.109 (4)0.709 (3)0.018*
O90.1329 (2)0.2581 (3)0.56658 (18)0.0135 (5)
H9A0.081 (3)0.185 (4)0.571 (3)0.020*
H9B0.121 (3)0.314 (5)0.513 (2)0.020*
O100.0781 (2)0.4862 (3)0.40873 (19)0.0194 (6)
H10A0.106 (4)0.505 (6)0.357 (2)0.029*
H10B0.016 (3)0.531 (5)0.392 (3)0.029*
N10.2963 (2)0.4907 (3)0.85098 (19)0.0060 (5)
C10.3938 (3)0.5761 (4)0.8822 (2)0.0055 (6)
C20.4007 (3)0.7107 (4)0.9553 (2)0.0073 (6)
H20.46990.77300.97440.009*
C30.3035 (3)0.7525 (4)1.0003 (2)0.0082 (6)
C40.2043 (3)0.6563 (4)0.9712 (2)0.0073 (6)
H40.13850.67611.00370.009*
C50.2035 (3)0.5320 (4)0.8944 (2)0.0070 (6)
C60.4912 (3)0.5242 (4)0.8255 (2)0.0068 (6)
C70.3007 (3)0.9081 (4)1.0720 (2)0.0077 (6)
C80.0974 (3)0.4387 (4)0.8469 (2)0.0072 (6)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Gd10.00489 (8)0.00531 (9)0.00486 (9)0.00011 (6)0.00130 (6)−0.00021 (6)
O10.0066 (11)0.0089 (11)0.0103 (12)−0.0013 (8)0.0017 (9)−0.0024 (9)
O20.0051 (11)0.0103 (11)0.0082 (11)−0.0021 (8)−0.0006 (9)0.0004 (8)
O30.0137 (12)0.0071 (11)0.0099 (12)−0.0012 (9)0.0034 (9)−0.0026 (9)
O40.0143 (13)0.0104 (12)0.0094 (12)−0.0038 (9)0.0059 (9)−0.0025 (9)
O50.0075 (12)0.0142 (11)0.0142 (12)−0.0027 (9)0.0030 (9)−0.0062 (9)
O60.0054 (11)0.0150 (12)0.0111 (12)0.0014 (9)0.0015 (9)−0.0024 (9)
O70.0132 (13)0.0111 (12)0.0086 (12)0.0047 (9)0.0023 (10)0.0035 (9)
O80.0084 (12)0.0096 (12)0.0166 (13)0.0008 (9)−0.0005 (10)−0.0012 (10)
O90.0135 (13)0.0173 (13)0.0088 (12)−0.0061 (9)−0.0027 (10)0.0041 (9)
O100.0237 (16)0.0199 (13)0.0141 (14)0.0057 (11)0.0010 (12)0.0048 (11)
N10.0057 (13)0.0058 (12)0.0065 (13)0.0006 (9)0.0012 (10)0.0008 (10)
C10.0072 (15)0.0040 (14)0.0056 (15)−0.0021 (11)0.0024 (12)0.0023 (11)
C20.0071 (15)0.0054 (14)0.0094 (16)−0.0029 (11)0.0015 (12)0.0004 (12)
C30.0097 (17)0.0102 (16)0.0042 (15)0.0004 (11)−0.0011 (12)0.0011 (11)
C40.0061 (15)0.0070 (14)0.0092 (16)0.0013 (11)0.0026 (12)0.0021 (12)
C50.0059 (15)0.0073 (15)0.0083 (16)0.0010 (11)0.0021 (12)0.0009 (12)
C60.0095 (16)0.0038 (14)0.0071 (16)0.0000 (11)0.0007 (12)0.0014 (11)
C70.0054 (15)0.0101 (15)0.0070 (16)0.0018 (11)−0.0017 (12)0.0000 (12)
C80.0065 (16)0.0060 (15)0.0095 (16)−0.0008 (11)0.0023 (12)0.0021 (12)
Geometric parameters (Å, °) top
Gd1—O2i2.335 (2)O7—H7B0.83 (2)
Gd1—O52.393 (2)O8—H8A0.82 (3)
Gd1—O92.437 (3)O8—H8B0.75 (2)
Gd1—O12.449 (2)O9—H9A0.82 (2)
Gd1—O72.471 (2)O9—H9B0.83 (2)
Gd1—O82.477 (2)O10—H10A0.81 (2)
Gd1—N12.488 (2)O10—H10B0.82 (3)
Gd1—O4ii2.517 (2)N1—C51.339 (4)
Gd1—O3ii2.530 (2)N1—C11.342 (4)
Gd1—C7ii2.880 (3)C1—C21.386 (4)
O1—C61.266 (4)C1—C61.504 (4)
O2—C61.250 (4)C2—C31.397 (4)
O2—Gd1iii2.335 (2)C2—H20.9500
O3—C71.264 (4)C3—C41.391 (4)
O3—Gd1iv2.530 (2)C3—C71.492 (4)
O4—C71.261 (4)C4—C51.374 (4)
O4—Gd1iv2.517 (2)C4—H40.9500
O5—C81.269 (4)C5—C81.513 (4)
O6—C81.245 (4)C7—Gd1iv2.880 (3)
O7—H7A0.82 (2)
O2i—Gd1—O5150.00 (8)C6—O1—Gd1123.22 (19)
O2i—Gd1—O998.27 (8)C6—O2—Gd1iii134.9 (2)
O5—Gd1—O973.52 (8)C7—O3—Gd1iv92.69 (17)
O2i—Gd1—O175.39 (7)C7—O4—Gd1iv93.35 (18)
O5—Gd1—O1128.84 (7)C8—O5—Gd1125.3 (2)
O9—Gd1—O1141.45 (7)Gd1—O7—H7A112 (3)
O2i—Gd1—O774.73 (7)Gd1—O7—H7B140 (3)
O5—Gd1—O794.71 (8)H7A—O7—H7B107 (4)
O9—Gd1—O7143.75 (8)Gd1—O8—H8A117 (3)
O1—Gd1—O772.28 (7)Gd1—O8—H8B121 (3)
O2i—Gd1—O877.00 (7)H8A—O8—H8B106 (4)
O5—Gd1—O873.01 (8)Gd1—O9—H9A119 (3)
O9—Gd1—O872.98 (8)Gd1—O9—H9B131 (3)
O1—Gd1—O8138.37 (7)H9A—O9—H9B109 (4)
O7—Gd1—O870.78 (8)H10A—O10—H10B98 (4)
O2i—Gd1—N1132.39 (8)C5—N1—C1118.9 (3)
O5—Gd1—N164.62 (8)C5—N1—Gd1120.3 (2)
O9—Gd1—N1129.04 (8)C1—N1—Gd1120.47 (19)
O1—Gd1—N164.48 (7)N1—C1—C2122.2 (3)
O7—Gd1—N169.63 (8)N1—C1—C6114.3 (3)
O8—Gd1—N1117.68 (8)C2—C1—C6123.4 (3)
O2i—Gd1—O4ii125.38 (7)C1—C2—C3118.4 (3)
O5—Gd1—O4ii81.63 (7)C1—C2—H2120.8
O9—Gd1—O4ii76.75 (8)C3—C2—H2120.8
O1—Gd1—O4ii76.74 (7)C4—C3—C2119.0 (3)
O7—Gd1—O4ii136.55 (8)C4—C3—C7119.1 (3)
O8—Gd1—O4ii144.83 (8)C2—C3—C7121.7 (3)
N1—Gd1—O4ii69.84 (8)C5—C4—C3118.7 (3)
O2i—Gd1—O3ii74.76 (7)C5—C4—H4120.7
O5—Gd1—O3ii126.13 (8)C3—C4—H4120.7
O9—Gd1—O3ii70.79 (8)N1—C5—C4122.7 (3)
O1—Gd1—O3ii70.88 (7)N1—C5—C8113.8 (3)
O7—Gd1—O3ii136.76 (8)C4—C5—C8123.4 (3)
O8—Gd1—O3ii129.52 (7)O2—C6—O1125.4 (3)
N1—Gd1—O3ii112.32 (8)O2—C6—C1117.9 (3)
O4ii—Gd1—O3ii51.91 (7)O1—C6—C1116.7 (3)
O2i—Gd1—C7ii100.19 (8)O4—C7—O3122.0 (3)
O5—Gd1—C7ii104.20 (8)O4—C7—C3119.5 (3)
O9—Gd1—C7ii71.79 (8)O3—C7—C3118.4 (3)
O1—Gd1—C7ii72.09 (8)O4—C7—Gd1iv60.73 (15)
O7—Gd1—C7ii144.11 (8)O3—C7—Gd1iv61.32 (15)
O8—Gd1—C7ii143.83 (9)C3—C7—Gd1iv176.6 (2)
N1—Gd1—C7ii91.16 (8)O6—C8—O5126.3 (3)
O4ii—Gd1—C7ii25.92 (7)O6—C8—C5117.7 (3)
O3ii—Gd1—C7ii25.99 (7)O5—C8—C5116.0 (3)
O2i—Gd1—O1—C6−147.2 (2)Gd1—N1—C1—C2171.2 (2)
O5—Gd1—O1—C612.7 (3)C5—N1—C1—C6−177.8 (3)
O9—Gd1—O1—C6127.9 (2)Gd1—N1—C1—C6−4.0 (3)
O7—Gd1—O1—C6−68.8 (2)N1—C1—C2—C32.6 (4)
O8—Gd1—O1—C6−97.2 (2)C6—C1—C2—C3177.5 (3)
N1—Gd1—O1—C66.5 (2)C1—C2—C3—C40.9 (4)
O4ii—Gd1—O1—C680.3 (2)C1—C2—C3—C7−173.7 (3)
O3ii—Gd1—O1—C6134.2 (2)C2—C3—C4—C5−4.3 (5)
C7ii—Gd1—O1—C6106.8 (2)C7—C3—C4—C5170.5 (3)
O2i—Gd1—O5—C8133.9 (2)C1—N1—C5—C4−1.1 (4)
O9—Gd1—O5—C8−148.4 (3)Gd1—N1—C5—C4−174.9 (2)
O1—Gd1—O5—C8−4.4 (3)C1—N1—C5—C8175.1 (3)
O7—Gd1—O5—C866.6 (2)Gd1—N1—C5—C81.3 (3)
O8—Gd1—O5—C8134.8 (3)C3—C4—C5—N14.6 (5)
N1—Gd1—O5—C81.8 (2)C3—C4—C5—C8−171.3 (3)
O4ii—Gd1—O5—C8−69.8 (2)Gd1iii—O2—C6—O162.9 (4)
O3ii—Gd1—O5—C8−98.3 (2)Gd1iii—O2—C6—C1−115.0 (3)
C7ii—Gd1—O5—C8−82.7 (2)Gd1—O1—C6—O2171.1 (2)
O2i—Gd1—N1—C5−151.4 (2)Gd1—O1—C6—C1−11.0 (3)
O5—Gd1—N1—C5−1.5 (2)N1—C1—C6—O2−172.4 (3)
O9—Gd1—N1—C536.4 (3)C2—C1—C6—O212.4 (4)
O1—Gd1—N1—C5173.1 (2)N1—C1—C6—O19.6 (4)
O7—Gd1—N1—C5−107.4 (2)C2—C1—C6—O1−165.6 (3)
O8—Gd1—N1—C5−53.6 (2)Gd1iv—O4—C7—O30.5 (3)
O4ii—Gd1—N1—C588.6 (2)Gd1iv—O4—C7—C3−176.1 (3)
O3ii—Gd1—N1—C5119.2 (2)Gd1iv—O3—C7—O4−0.5 (3)
C7ii—Gd1—N1—C5103.6 (2)Gd1iv—O3—C7—C3176.1 (3)
O2i—Gd1—N1—C134.9 (3)C4—C3—C7—O445.8 (4)
O5—Gd1—N1—C1−175.3 (2)C2—C3—C7—O4−139.6 (3)
O9—Gd1—N1—C1−137.4 (2)C4—C3—C7—O3−131.0 (3)
O1—Gd1—N1—C1−0.6 (2)C2—C3—C7—O343.6 (4)
O7—Gd1—N1—C178.9 (2)Gd1—O5—C8—O6177.7 (2)
O8—Gd1—N1—C1132.6 (2)Gd1—O5—C8—C5−1.8 (4)
O4ii—Gd1—N1—C1−85.1 (2)N1—C5—C8—O6−179.3 (3)
O3ii—Gd1—N1—C1−54.5 (2)C4—C5—C8—O6−3.1 (4)
C7ii—Gd1—N1—C1−70.1 (2)N1—C5—C8—O50.2 (4)
C5—N1—C1—C2−2.6 (4)C4—C5—C8—O5176.4 (3)
Symmetry codes: (i) −x+1, y−1/2, −z+3/2; (ii) x, −y+3/2, z−1/2; (iii) −x+1, y+1/2, −z+3/2; (iv) x, −y+3/2, z+1/2.
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
O7—H7A···O1i0.82 (2)2.02 (3)2.794 (3)157 (4)
O7—H7B···O3v0.83 (2)1.97 (2)2.795 (3)175 (4)
O8—H8A···O6vi0.82 (3)1.80 (3)2.621 (3)171 (4)
O8—H8B···O4vii0.75 (2)2.22 (3)2.933 (3)158 (4)
O9—H9A···O6vi0.82 (2)2.01 (3)2.800 (3)161 (4)
O9—H9B···O100.83 (2)1.91 (3)2.723 (3)166 (4)
O10—H10A···O8vii0.81 (2)2.24 (3)3.051 (4)173 (4)
O10—H10B···O9viii0.82 (3)2.45 (3)3.169 (4)148 (4)
Symmetry codes: (i) −x+1, y−1/2, −z+3/2; (v) x, y−1, z; (vi) −x, y−1/2, −z+3/2; (vii) x, −y+1/2, z−1/2; (viii) −x, −y+1, −z+1.
Table 1
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
O7—H7A···O1i0.82 (2)2.02 (3)2.794 (3)157 (4)
O7—H7B···O3ii0.83 (2)1.97 (2)2.795 (3)175 (4)
O8—H8A···O6iii0.82 (3)1.80 (3)2.621 (3)171 (4)
O8—H8B···O4iv0.75 (2)2.22 (3)2.933 (3)158 (4)
O9—H9A···O6iii0.82 (2)2.01 (3)2.800 (3)161 (4)
O9—H9B···O100.83 (2)1.91 (3)2.723 (3)166 (4)
O10—H10A···O8iv0.81 (2)2.24 (3)3.051 (4)173 (4)
O10—H10B···O9v0.82 (3)2.45 (3)3.169 (4)148 (4)
Symmetry codes: (i) −x+1, y−1/2, −z+3/2; (ii) x, y−1, z; (iii) −x, y−1/2, −z+3/2; (iv) x, −y+1/2, z−1/2; (v) −x, −y+1, −z+1.
Acknowledgements top

This work was supported by the Education Department of Henan Province (2009B150026).

references
References top

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