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Acta Cryst. (2009). E65, m1214-m1215    [ doi:10.1107/S1600536809036393 ]

Poly[diaqua([mu]2-5-carboxypyridine-3-carboxylato-[kappa]2N:O3)hemi([mu]2-oxalato-[kappa]4O1,O2:O1',O2')([mu]4-pyridine-3,5-dicarboxylato-[kappa]4N:O3:O3':O5)silver(I)terbium(III)]

H.-F. Guo, L. Qin and X.-Y. Hao

Abstract top

In the title coordination polymer, [AgTb(C7H3NO4)(C7H4NO4)(C2O4)0.5(H2O)2]n, the TbIII ion is eight-coordinated by three O atoms from three different pydc (H2pydc = pyridine-3,5-dicarboxylic acid) ligands, one O atom from one Hpydc ligand, two O atoms from one oxalate ligand and two water molecules in a distorted square-antiprismatic geometry. The AgI ion is coordinated in an almost linear fashion by two pyridyl N atoms from one pydc and one Hpydc ligand and has weak interactions with two carboxylate O atoms. The carboxylate groups of pydc and Hpydc ligands link Tb centers, forming a one-dimensional chain. The oxalate adopts a tetradentate bis-chelating coordination mode, connecting the chains into a two-dimensional layer. These layers are further assembled via [Ag(pydc)(Hpydc)] pillars and O-H...O and C-H...O hydrogen bonds into a three-dimensional coordination framework.

Comment top

The design and construction of transition–lanthanide metal complexes has gained great recognition over the last decade because of their intriguing network topolopies and potential applications, and due to their magnetic properties, their capacity for gas storage, as luminescent materials, and so on (Barbour, 2006; Kepert, 2006; Kong et al., 2008; Rao et al., 2004; Zhang et al., 2005). Pyridine-3,5-dicarboxylic acid (H2pydc) is a multifunctional bridging ligand possessing of O and N donors, which can thus be chosen to construct lanthanide–transition heterometallic complex via the carboxyl O atoms binding to lanthanides and N atoms bonding to transition metal ions such as AgI or CuI (Wu et al., 2008). On the basis of above considerations, we utilize H2pydc, mixed 4d–4f metal ions and nitric acid as our building blocks. A new three-dimensional 4d–4f coordination framework resulted from the hydrothermal treatment of Tb2O3, AgNO3, oxalic acid, H2pydc and nitric acid in water.

As depicted in Fig. 1, the asymmtric unit of the title compound contains one TbIII ion, one AgI ion, half an oxalate ligand, one pydc ligand, one Hpydc ligand and two water molecules. The TbIII ion is eight-coordinated in a distorted square-antiprismatic coordination geometry by three O atoms from three different pydc ligands, one O atom from one Hpydc ligand, two O atoms from one oxalate ligand and two water molecules. The AgI ion is located in an almost linear configuration, defined by two N atoms from one pydc and one Hpydc ligands. The carboxylate groups of the pydc and Hpydc ligands link TbIII center to form a one-dimensional chain with a shortest Tb···Tb distance of 5.261 (3) Å (Fig. 2a). The oxalate adopts tetradentate bischelating coordination mode to connect the neighboring chains into a two-dimensional layer (Fig. 2b). These layers are further assembled via [Ag(pydc)(Hpydc)] pillars into a three-dimensional coordination framework (Fig. 3). O—H···O and C—H···O hydrogen bonds (Table 1) involving the carboxyl group and coordinated water molecules enhance the stability of the three-dimensional network.

Related literature top

For general background to transition metal–lanthanide complexes, see: Barbour (2006); Kepert (2006); Kong et al. (2008); Rao et al. (2004); Wu et al. (2008); Zhang et al. (2005).

Experimental top

A mixture of Tb2O3 (0.183 g, 0.5 mmol), AgNO3 (0.169 g, 1 mmol), H2pydc (0.167 g, 1 mmol), oxalic acid (0.09 g, 1 mmol), HNO3 (0.12 ml) and H2O (10 ml) was placed in a 23 ml Teflon-lined reactor, which was heated to 443 K for 3 d and then cooled to room temperature at a rate of 10 K h-1. The colorless block crystals obtained were washed with water and dried in air (yield 46% based on Tb).

Refinement top

C-bound H atoms were placed at calculated positions and treated as riding on the parent C atoms, with C—H = 0.93 Å, and with Uiso(H) = 1.2Ueq(C). Water H atoms were tentatively located in difference Fourier maps and refined with distance restraints of O–H = 0.84 (1) and H···H = 1.39 (1) Å, and with Uiso(H) = 1.5Ueq(O). Carboxyl H (H3A) atom was refined isotropically.

Computing details top

Data collection: APEX2 (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008) and DIAMOND (Brandenburg, 1999); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The asymmetric unit of the title compound. Non-H atoms are shown as 50% probability displacement ellipsoids. H atoms have been omitted for clarity. [Symmetry codes: (i) 1-x, -y, -z; (ii) 2-x, 1-y, -z; (iii) x, -1+y, z.]
[Figure 2] Fig. 2. (a) A view of the one-dimensional chain in the title compound. (b) A polyhedral view of the two-dimensional layer. H atoms have been omitted for clarity.
[Figure 3] Fig. 3. A polyhedral view of the three-dimensional framework. H atoms have been omitted for clarity.
Poly[diaqua(µ2-5-carboxypyridine-3-carboxylato- κ2N:O3)hemi(µ2-oxalato- κ4O1,O2:O1',O2')(µ4- pyridine-3,5-dicarboxylato- κ4N:O3:O3':O5)silver(I)terbium(III)] top
Crystal data top
[AgTb(C7H3NO4)(C7H4NO4)(C2O4)0.5(H2O)2]Z = 2
Mr = 678.05F(000) = 646
Triclinic, P1Dx = 2.615 Mg m−3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 7.592 (3) ÅCell parameters from 3600 reflections
b = 8.249 (3) Åθ = 1.4–28°
c = 14.241 (6) ŵ = 5.29 mm−1
α = 98.956 (4)°T = 293 K
β = 99.556 (4)°Block, colorless
γ = 95.839 (5)°0.30 × 0.24 × 0.19 mm
V = 861.3 (6) Å3
Data collection top
Bruker APEXII CCD
diffractometer		3032 independent reflections
Radiation source: fine-focus sealed tube2862 reflections with I > 2σ(I)
graphiteRint = 0.018
φ and ω scansθmax = 25.2°, θmin = 2.5°
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)		h = −9→6
Tmin = 0.251, Tmax = 0.378k = −9→9
4416 measured reflectionsl = −16→17
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)] = 0.023Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.062H atoms treated by a mixture of independent and constrained refinement
S = 1.09 w = 1/[σ2(Fo2) + (0.0323P)2]
where P = (Fo2 + 2Fc2)/3
3032 reflections(Δ/σ)max = 0.049
284 parametersΔρmax = 0.85 e Å−3
0 restraintsΔρmin = −0.79 e Å−3
Crystal data top
[AgTb(C7H3NO4)(C7H4NO4)(C2O4)0.5(H2O)2]γ = 95.839 (5)°
Mr = 678.05V = 861.3 (6) Å3
Triclinic, P1Z = 2
a = 7.592 (3) ÅMo Kα radiation
b = 8.249 (3) ŵ = 5.29 mm−1
c = 14.241 (6) ÅT = 293 K
α = 98.956 (4)°0.30 × 0.24 × 0.19 mm
β = 99.556 (4)°
Data collection top
Bruker APEXII CCD
diffractometer		3032 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)		2862 reflections with I > 2σ(I)
Tmin = 0.251, Tmax = 0.378Rint = 0.018
4416 measured reflectionsθmax = 25.2°
Refinement top
R[F2 > 2σ(F2)] = 0.023H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.062Δρmax = 0.85 e Å−3
S = 1.09Δρmin = −0.79 e Å−3
3032 reflectionsAbsolute structure: ?
284 parametersFlack parameter: ?
0 restraintsRogers parameter: ?
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
Tb10.80756 (3)0.29706 (2)0.080761 (13)0.01369 (8)
Ag10.17209 (6)0.40250 (5)0.53284 (3)0.03343 (12)
O10.4372 (5)0.2187 (4)0.2009 (2)0.0305 (8)
O1W0.7121 (5)0.5291 (4)0.0096 (2)0.0278 (8)
H1W0.77420.5573−0.03020.042*
H2W0.63160.59040.01650.042*
O20.6205 (4)0.4300 (4)0.1747 (2)0.0255 (7)
O2W1.0914 (4)0.1769 (4)0.0759 (2)0.0253 (7)
H3W1.10700.13930.02000.038*
H4W1.18760.19050.11660.038*
O30.4778 (6)0.9748 (5)0.2896 (3)0.0449 (10)
O40.3416 (5)1.0334 (4)0.4169 (2)0.0346 (8)
O51.0531 (4)0.5114 (3)0.1239 (2)0.0203 (7)
O90.5031 (4)0.2064 (3)−0.0119 (2)0.0209 (7)
N10.3034 (5)0.5246 (4)0.4335 (3)0.0234 (8)
N20.8987 (5)0.7556 (4)0.3678 (2)0.0192 (8)
C10.3576 (6)0.4244 (5)0.3627 (3)0.0231 (10)
H10.33770.31060.36010.028*
C20.4420 (6)0.4845 (5)0.2934 (3)0.0188 (9)
C30.4629 (6)0.6531 (5)0.2942 (3)0.0204 (9)
H30.51620.69650.24760.025*
C40.4032 (6)0.7568 (5)0.3654 (3)0.0200 (9)
C50.3273 (6)0.6886 (5)0.4347 (3)0.0208 (10)
H50.29170.75870.48380.025*
C60.5041 (6)0.3688 (5)0.2177 (3)0.0216 (10)
C70.4047 (6)0.9388 (6)0.3621 (3)0.0246 (10)
C80.9565 (6)0.6777 (5)0.2901 (3)0.0165 (9)
H80.96580.56520.28490.020*
C91.0023 (6)0.7592 (5)0.2182 (3)0.0169 (9)
C100.9849 (6)0.9277 (5)0.2249 (3)0.0168 (9)
H101.01420.98480.17700.020*
C110.9234 (6)1.0091 (5)0.3038 (3)0.0166 (9)
C120.8845 (6)0.9188 (5)0.3740 (3)0.0201 (9)
H120.84690.97320.42790.024*
C131.0667 (6)0.6684 (5)0.1333 (3)0.0151 (9)
C150.4376 (6)0.0595 (5)−0.0196 (3)0.0168 (9)
O61.1310 (4)0.7500 (3)0.0780 (2)0.0211 (7)
C140.9003 (6)1.1915 (5)0.3113 (3)0.0202 (10)
O70.8768 (5)1.2673 (4)0.3899 (2)0.0328 (8)
O100.2771 (4)−0.0028 (3)−0.0543 (2)0.0219 (7)
O80.9101 (5)1.2520 (4)0.2359 (2)0.0262 (8)
H3A0.461 (9)1.076 (8)0.276 (4)0.056 (18)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Tb10.01701 (13)0.01146 (12)0.01419 (12)0.00272 (8)0.00639 (8)0.00282 (8)
Ag10.0419 (3)0.0381 (2)0.0290 (2)0.00612 (19)0.01825 (17)0.01948 (17)
O10.049 (2)0.0185 (16)0.0251 (17)0.0037 (16)0.0116 (15)0.0024 (13)
O1W0.033 (2)0.0227 (16)0.0388 (19)0.0149 (15)0.0194 (16)0.0180 (14)
O20.0281 (19)0.0287 (17)0.0241 (16)0.0080 (15)0.0150 (14)0.0039 (13)
O2W0.0241 (19)0.0321 (17)0.0215 (16)0.0081 (15)0.0070 (13)0.0039 (13)
O30.067 (3)0.0275 (19)0.055 (2)0.018 (2)0.035 (2)0.0209 (18)
O40.045 (2)0.0241 (17)0.0375 (19)0.0126 (17)0.0136 (17)0.0024 (15)
O50.0284 (18)0.0129 (14)0.0208 (15)0.0011 (13)0.0096 (13)0.0029 (11)
O90.0192 (17)0.0147 (14)0.0288 (16)0.0013 (13)0.0027 (13)0.0063 (12)
N10.031 (2)0.025 (2)0.0207 (19)0.0084 (17)0.0136 (17)0.0089 (15)
N20.022 (2)0.0199 (18)0.0191 (18)0.0048 (16)0.0083 (15)0.0085 (14)
C10.027 (3)0.019 (2)0.028 (2)0.005 (2)0.011 (2)0.0102 (18)
C20.019 (2)0.023 (2)0.016 (2)0.0047 (19)0.0063 (17)0.0045 (17)
C30.020 (2)0.023 (2)0.020 (2)0.0026 (19)0.0065 (18)0.0074 (17)
C40.016 (2)0.017 (2)0.027 (2)0.0037 (18)0.0038 (18)0.0054 (17)
C50.022 (3)0.025 (2)0.017 (2)0.0078 (19)0.0061 (18)0.0011 (17)
C60.027 (3)0.022 (2)0.017 (2)0.008 (2)0.0038 (19)0.0046 (17)
C70.019 (3)0.026 (2)0.028 (2)0.003 (2)0.0013 (19)0.008 (2)
C80.015 (2)0.017 (2)0.018 (2)0.0021 (17)0.0017 (17)0.0056 (16)
C90.019 (2)0.018 (2)0.014 (2)0.0030 (18)0.0041 (17)0.0033 (16)
C100.020 (2)0.016 (2)0.016 (2)0.0018 (18)0.0057 (17)0.0056 (16)
C110.018 (2)0.018 (2)0.015 (2)0.0034 (18)0.0038 (17)0.0042 (16)
C120.023 (3)0.023 (2)0.015 (2)0.0060 (19)0.0040 (18)0.0027 (17)
C130.017 (2)0.016 (2)0.0119 (19)0.0015 (17)0.0021 (16)0.0009 (16)
C150.021 (2)0.015 (2)0.014 (2)0.0039 (19)0.0058 (17)0.0000 (16)
O60.0315 (19)0.0181 (15)0.0161 (14)0.0030 (14)0.0113 (13)0.0034 (12)
C140.025 (3)0.017 (2)0.019 (2)0.0035 (19)0.0048 (18)0.0037 (17)
O70.058 (3)0.0231 (17)0.0228 (17)0.0110 (17)0.0220 (16)0.0011 (13)
O100.0198 (18)0.0157 (14)0.0303 (16)0.0015 (13)0.0053 (13)0.0041 (12)
O80.045 (2)0.0196 (15)0.0179 (15)0.0103 (15)0.0109 (14)0.0071 (12)
Geometric parameters (Å, °) top
Tb1—O22.346 (3)N2—C81.352 (5)
Tb1—O52.364 (3)N2—C121.351 (5)
Tb1—O6i2.365 (3)N2—Ag1iv2.162 (4)
Tb1—O8ii2.317 (3)C1—C21.388 (6)
Tb1—O92.444 (3)C1—H10.9300
Tb1—O10iii2.401 (3)C2—C31.382 (6)
Tb1—O1W2.421 (3)C2—C61.494 (6)
Tb1—O2W2.468 (3)C3—C41.388 (6)
Ag1—N12.172 (4)C3—H30.9300
Ag1—N2iv2.162 (4)C4—C51.386 (6)
Ag1—O7v2.772 (3)C4—C71.508 (6)
Ag1—O7vi2.859 (3)C5—H50.9300
Ag1—Ag1vii3.2867 (12)C8—C91.381 (6)
O1—C61.260 (5)C8—H80.9300
O1W—H1W0.8401C9—C101.400 (6)
O1W—H2W0.8400C9—C131.500 (6)
O2—C61.263 (6)C10—C111.391 (6)
O2W—H3W0.8402C10—H100.9300
O2W—H4W0.8400C11—C121.388 (6)
O3—C71.309 (6)C11—C141.522 (6)
O3—H3A0.90 (6)C12—H120.9300
O4—C71.207 (5)C13—O61.241 (5)
O5—C131.273 (5)C15—O101.260 (5)
O9—C151.244 (5)C15—C15iii1.535 (8)
N1—C51.343 (6)C14—O71.244 (5)
N1—C11.348 (5)C14—O81.262 (5)
O8ii—Tb1—O275.61 (11)C8—N2—Ag1iv114.8 (3)
O8ii—Tb1—O6i141.96 (11)C12—N2—Ag1iv127.0 (3)
O2—Tb1—O6i142.34 (10)N1—C1—C2122.6 (4)
O8ii—Tb1—O582.16 (11)N1—C1—H1118.7
O2—Tb1—O596.02 (11)C2—C1—H1118.7
O6i—Tb1—O589.03 (10)C3—C2—C1118.6 (4)
O8ii—Tb1—O10iii81.37 (10)C3—C2—C6120.7 (4)
O2—Tb1—O10iii109.81 (11)C1—C2—C6120.7 (4)
O6i—Tb1—O10iii85.00 (10)C2—C3—C4119.1 (4)
O5—Tb1—O10iii144.60 (10)C2—C3—H3120.5
O8ii—Tb1—O1W135.70 (10)C4—C3—H3120.5
O2—Tb1—O1W71.23 (11)C5—C4—C3119.0 (4)
O6i—Tb1—O1W74.71 (10)C5—C4—C7120.2 (4)
O5—Tb1—O1W73.14 (11)C3—C4—C7120.6 (4)
O10iii—Tb1—O1W137.38 (11)N1—C5—C4122.3 (4)
O8ii—Tb1—O9125.23 (12)N1—C5—H5118.9
O2—Tb1—O975.56 (11)C4—C5—H5118.9
O6i—Tb1—O979.71 (11)O1—C6—O2124.7 (4)
O5—Tb1—O9146.28 (10)O1—C6—C2118.4 (4)
O10iii—Tb1—O966.38 (9)O2—C6—C2116.9 (4)
O1W—Tb1—O973.25 (11)O4—C7—O3126.2 (4)
O8ii—Tb1—O2W73.67 (11)O4—C7—C4124.1 (4)
O2—Tb1—O2W147.82 (10)O3—C7—C4109.6 (4)
O6i—Tb1—O2W68.50 (10)N2—C8—C9122.3 (4)
O5—Tb1—O2W70.60 (11)N2—C8—H8118.8
O10iii—Tb1—O2W74.76 (11)C9—C8—H8118.8
O1W—Tb1—O2W127.82 (11)C8—C9—C10118.9 (4)
O9—Tb1—O2W131.32 (10)C8—C9—C13120.7 (4)
N2iv—Ag1—N1164.83 (14)C10—C9—C13120.4 (4)
N2iv—Ag1—Ag1vii108.80 (10)C11—C10—C9119.4 (4)
N1—Ag1—Ag1vii86.10 (10)C11—C10—H10120.3
N2iv—Ag1—O7v93.85 (11)C9—C10—H10120.3
N1—Ag1—O7v92.40 (13)C12—C11—C10117.9 (4)
N1—Ag1—O7vi83.19 (11)C12—C11—C14122.0 (4)
N2iv—Ag1—O7vi107.77 (11)C10—C11—C14120.1 (4)
O7v—Ag1—O7vi108.60 (9)N2—C12—C11123.2 (4)
Tb1—O1W—H1W113.8N2—C12—H12118.4
Tb1—O1W—H2W134.5C11—C12—H12118.4
H1W—O1W—H2W111.6O6—C13—O5124.4 (4)
C6—O2—Tb1129.6 (3)O6—C13—C9118.5 (3)
Tb1—O2W—H3W114.5O5—C13—C9117.1 (4)
Tb1—O2W—H4W131.1O9—C15—O10126.9 (4)
H3W—O2W—H4W111.7O9—C15—C15iii117.3 (5)
C7—O3—H3A113 (4)O10—C15—C15iii115.7 (4)
C13—O5—Tb1133.9 (3)C13—O6—Tb1i137.7 (3)
C15—O9—Tb1118.8 (3)O7—C14—O8126.2 (4)
C5—N1—C1118.3 (4)O7—C14—C11118.2 (4)
C5—N1—Ag1125.6 (3)O8—C14—C11115.6 (4)
C1—N1—Ag1116.1 (3)C15—O10—Tb1iii120.5 (2)
C8—N2—C12118.2 (4)C14—O8—Tb1viii155.4 (3)
Symmetry codes: (i) −x+2, −y+1, −z; (ii) x, y−1, z; (iii) −x+1, −y, −z; (iv) −x+1, −y+1, −z+1; (v) x−1, y−1, z; (vi) −x+1, −y+2, −z+1; (vii) −x, −y+1, −z+1; (viii) x, y+1, z.
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
O1W—H1W···O5i0.842.082.820 (5)147
O1W—H1W···O2Wi0.842.553.221 (5)138
O1W—H2W···O9ix0.842.052.855 (4)159
O2W—H3W···O10x0.842.132.839 (4)142
O2W—H4W···O1x0.842.042.873 (5)173
O3—H3A···O1viii0.90 (6)1.71 (7)2.554 (5)154 (6)
C10—H10···O2Wviii0.932.403.314 (6)169
Symmetry codes: (i) −x+2, −y+1, −z; (ix) −x+1, −y+1, −z; (x) x+1, y, z; (viii) x, y+1, z.
Table 1
Selected geometric parameters (Å) top
Tb1—O22.346 (3)Tb1—O1W2.421 (3)
Tb1—O52.364 (3)Tb1—O2W2.468 (3)
Tb1—O6i2.365 (3)Ag1—N12.172 (4)
Tb1—O8ii2.317 (3)Ag1—N2iv2.162 (4)
Tb1—O92.444 (3)Ag1—O7v2.772 (3)
Tb1—O10iii2.401 (3)Ag1—O7vi2.859 (3)
Symmetry codes: (i) −x+2, −y+1, −z; (ii) x, y−1, z; (iii) −x+1, −y, −z; (iv) −x+1, −y+1, −z+1; (v) x−1, y−1, z; (vi) −x+1, −y+2, −z+1.
Table 2
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
O1W—H1W···O5i0.842.082.820 (5)147
O1W—H1W···O2Wi0.842.553.221 (5)138
O1W—H2W···O9vii0.842.052.855 (4)159
O2W—H3W···O10viii0.842.132.839 (4)142
O2W—H4W···O1viii0.842.042.873 (5)173
O3—H3A···O1ix0.90 (6)1.71 (7)2.554 (5)154 (6)
C10—H10···O2Wix0.932.403.314 (6)169
Symmetry codes: (i) −x+2, −y+1, −z; (vii) −x+1, −y+1, −z; (viii) x+1, y, z; (ix) x, y+1, z.
Acknowledgements top

The authors kindly acknowledge Zhao Qing University for supporting this work.

references
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