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Acta Cryst. (2008). E64, m1433    [ doi:10.1107/S1600536808033230 ]

Poly[[aquatri-[mu]3-hydroxido-([mu]4-2-phosphonatoethanesulfonato)dierbium(III)] monohydrate]

A. Sonnauer and N. Stock

Abstract top

The crystal structure of the title compound, {[Er2(C2H4O6PS)(OH)3(H2O)]·H2O}n, consists of two Er3+ ions, one (C2H4O6PS)3- ion, three OH- ions, and two water molecule. The Er3+ ions form ErO8 polyhedra., which are connected by [mu]- and [mu]3-O atoms. Thus, inorganic Er-O-Er layers of edge- and face-sharing polyhedra are observed. Whereas most often in metal phosphonosulfonates the organic linker bridges adjacent layers, in the title compound, the (O3PC2H4SO3)3- anion is only connected to one Er-O-Er layer. Short interatomic O...O distances [2.898 (8), 2.997 (14) and 2.768 (10) Å] indicate hydrogen bonding between the layers. The noncoordinated water molecules are located between the layers.

Comment top

Inorganic–organic hybrid materials based on metal carboxylates, sulfonates and phosphonates are intensively investigated due to their potential application i.e. in the field of gas separation, storage, as well as catalysis, or as sensor materials. We are interested in the use of organic ligands containing two or more different functional groups for the synthesis of functionalized hybrid compounds. Although a large number of metal phosphonates and metal sulfonates have been reported in the literature, compounds based on ligands containing simultaneously a phosphonic as well as a sulfonic acid group have only recently been investigated. These few studies are limited to the use of linker molecules based on rigid phosphonoarylsulfonic acids (Benedetto et al., 1997; Adani et al., 1998; Du et al., 2006a,b; Du, Li et al., 2007; Du, Prosvirin & Mao, 2007; Du, Xu et al., 2007). Our group has started a systematic investigation using the flexible linker 2-phosphonoethansulfonic acid, which has been recently reported in the literature (Sonnauer et al., 2007; Sonnauer & Stock, 2008a,b). Here we describe the crystal structure of the new rare earth phosphonatosulfonate [Er2(O3PC2H4SO3)(OH)3(H2O)]H2O, which was obtained during a high-throughput screening experiment.

The title compound consists of two crystallographic independent erbium ions, one fully deprotonated (O3PC2H4SO3)3- anion, three hydroxide ions, as well as two water molecules (one is coordinated to a erbium ion) (Fig. 1). The erbium ions are coordinated eightfold by oxygen atoms and form ErO8 polyhedra (Fig. 2), which are linked (edge- and face-sharing) to inorganic layers Er–O–Er in the ab-plane (Fig. 3). While most often in metal phosphonosulfonates the organic linker bridges adjacent layers, in [Er2(O3PC2H4SO3)(OH)3(H2O)]H2O the anion (O3PC2H4SO3)3- is only connected to one Er–O–Er layer. These layers are further linked via hydrogen bonds into a three-dimensional structure (Fig. 4). The non-coordinating H2O molecules are located in between the layers.

Related literature top

For related structures, see: Sonnauer et al. (2007); Sonnauer & Stock (2008a,b); Benedetto et al. (1997); Adani et al. (1998); Du et al. (2006a,b); Du, Li et al. (2007); Du, Prosvirin & Mao (2007); Du, Xu et al. (2007).

Experimental top

H2O3PC2H4SO3H was synthesized as previously reported (Sonnauer & Stock, 2008b). All other reagents were of analytical grade (Aldrich and Fluka) and were used without furhter purification. For the synthesis a special high-throughput reactor system was used. 79 µl (0.016 mmol) of 0.2 M Er(CH3CO2)3.4H2O, 53.2 µl (0.032 mmol) of 0.5 M H2O3PC2H4SO3H, 23.7 µl (0.048 mmol) of 2.0 M NaOH, and 54 µl H2O were filled in a teflon reactor and heated to 160 °C for 48 h. After filtration the pink rod-shaped single crystals were isolated.

Refinement top

The H atoms connected to C atoms were positioned with idealized geometry and were refined isotropically with Ueq(H) = 1.2 Ueq(C) of the parent atom using a riding model with C—H = 0.97 Å. The H atoms connected to O atoms could not be located from the difference Fourier map and were omitted from refinement.

Computing details top

Data collection: IPDS Program Package (Stoe & Cie, 1998); cell refinement: IPDS Program Package (Stoe & Cie, 1998); data reduction: IPDS Program Package (Stoe & Cie, 1998); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg & Putz, 1999); software used to prepare material for publication: publCIF (Westrip, 2008).

Figures top
[Figure 1] Fig. 1. Asymmetric unit of the title compound. Displacement ellipsoides are drawn at 50% propability level.
[Figure 2] Fig. 2. First coordination sphere of the erbium ions.
[Figure 3] Fig. 3. Inorganic Er–O–Er layer in the ab-plane of edge- and face-sharing ErO8 polyhedra.
[Figure 4] Fig. 4. The anions (O3PC2H4SO3)3- are connected to one Er–O–Er layer at a time. The layers are linked via hydrogen bonds between the sulfonate groups and the coordinating water molecules into a three-dimensional structure.
Poly[[aquatri-µ3-hydroxido-(µ4-2-phosphonatoethanesulfonato)dierbium(III)] monohydrate] top
Crystal data top
[Er2(C2H4O6PS)(OH)3(H2O)]·H2OZ = 2
Mr = 608.65F(000) = 554
Triclinic, P1Dx = 3.611 Mg m−3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 5.8621 (6) ÅCell parameters from 4793 reflections
b = 9.0443 (9) Åθ = 2.5–28°
c = 11.6240 (11) ŵ = 15.29 mm−1
α = 105.543 (12)°T = 293 K
β = 101.713 (11)°Rod, pink
γ = 101.885 (11)°0.08 × 0.07 × 0.06 mm
V = 558.81 (10) Å3
Data collection top
Stoe IPDS-1
diffractometer		2664 independent reflections
Radiation source: fine-focus sealed tube2207 reflections with I > 2σ(I)
graphiteRint = 0.041
φ scansθmax = 28.1°, θmin = 2.4°
Absorption correction: ψ scan
(X-RED and X-SHAPE; Stoe & Cie, 1999)		h = −7→7
Tmin = 0.293, Tmax = 0.399k = −11→11
4731 measured reflectionsl = −15→15
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.031H-atom parameters constrained
wR(F2) = 0.082 w = 1/[σ2(Fo2) + (0.0577P)2]
where P = (Fo2 + 2Fc2)/3
S = 0.97(Δ/σ)max = 0.001
2664 reflectionsΔρmax = 1.61 e Å−3
155 parametersΔρmin = −2.07 e Å−3
0 restraintsExtinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.0044 (5)
Crystal data top
[Er2(C2H4O6PS)(OH)3(H2O)]·H2Oγ = 101.885 (11)°
Mr = 608.65V = 558.81 (10) Å3
Triclinic, P1Z = 2
a = 5.8621 (6) ÅMo Kα radiation
b = 9.0443 (9) ŵ = 15.29 mm−1
c = 11.6240 (11) ÅT = 293 K
α = 105.543 (12)°0.08 × 0.07 × 0.06 mm
β = 101.713 (11)°
Data collection top
Stoe IPDS-1
diffractometer		2664 independent reflections
Absorption correction: ψ scan
(X-RED and X-SHAPE; Stoe & Cie, 1999)		2207 reflections with I > 2σ(I)
Tmin = 0.293, Tmax = 0.399Rint = 0.041
4731 measured reflectionsθmax = 28.1°
Refinement top
R[F2 > 2σ(F2)] = 0.031H-atom parameters constrained
wR(F2) = 0.082Δρmax = 1.61 e Å−3
S = 0.97Δρmin = −2.07 e Å−3
2664 reflectionsAbsolute structure: ?
155 parametersFlack parameter: ?
0 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
Er10.21965 (5)0.71416 (3)0.57132 (3)0.00796 (12)
Er20.27992 (5)1.10732 (3)0.55352 (3)0.00839 (12)
S10.6239 (4)0.2840 (2)0.86984 (18)0.0197 (4)
P10.6867 (3)0.5153 (2)0.65414 (16)0.0080 (3)
O10.5161 (10)0.6197 (6)0.6590 (5)0.0150 (10)
O20.5556 (9)0.3377 (5)0.5872 (5)0.0106 (9)
O30.8809 (9)0.5494 (6)0.5852 (5)0.0129 (10)
O40.5879 (13)0.2641 (8)0.9845 (6)0.0324 (15)
O50.3963 (11)0.2164 (7)0.7714 (5)0.0214 (12)
O60.8156 (13)0.2224 (8)0.8314 (7)0.0323 (15)
O7−0.0251 (9)1.0829 (6)0.3821 (5)0.0110 (9)
O80.0459 (10)0.7988 (6)0.4152 (5)0.0170 (11)
O90.5197 (9)0.9454 (5)0.6002 (5)0.0100 (9)
O100.3173 (12)0.8253 (7)0.7926 (6)0.0255 (13)
C10.8513 (15)0.5462 (9)0.8095 (7)0.0185 (15)
H1A0.97600.49070.80570.022*
H1B0.93280.65920.84790.022*
C20.7080 (16)0.4931 (10)0.8961 (7)0.0217 (16)
H2A0.56210.52870.88640.026*
H2B0.80530.54640.98130.026*
O110.093 (2)1.0351 (13)0.9079 (12)0.078 (4)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Er10.00654 (18)0.00560 (17)0.01466 (18)0.00295 (11)0.00471 (12)0.00566 (12)
Er20.00577 (18)0.00797 (17)0.01466 (18)0.00329 (12)0.00454 (12)0.00646 (12)
S10.0221 (10)0.0209 (9)0.0176 (9)0.0061 (8)0.0051 (8)0.0086 (7)
P10.0070 (8)0.0064 (7)0.0131 (8)0.0029 (6)0.0043 (6)0.0053 (6)
O10.015 (3)0.015 (2)0.022 (3)0.012 (2)0.008 (2)0.009 (2)
O20.010 (2)0.009 (2)0.015 (2)0.0000 (18)0.0045 (19)0.0069 (18)
O30.010 (3)0.017 (2)0.016 (2)0.004 (2)0.008 (2)0.009 (2)
O40.043 (4)0.037 (4)0.018 (3)0.006 (3)0.006 (3)0.016 (3)
O50.019 (3)0.025 (3)0.012 (2)0.000 (2)−0.001 (2)0.001 (2)
O60.032 (4)0.035 (4)0.039 (4)0.019 (3)0.015 (3)0.014 (3)
O70.004 (2)0.012 (2)0.016 (2)0.0030 (18)0.0005 (19)0.0030 (18)
O80.020 (3)0.024 (3)0.018 (3)0.019 (2)0.009 (2)0.012 (2)
O90.007 (2)0.009 (2)0.015 (2)0.0002 (18)0.0050 (19)0.0058 (18)
O100.032 (4)0.027 (3)0.022 (3)0.015 (3)0.009 (3)0.009 (2)
C10.015 (4)0.018 (4)0.020 (4)−0.001 (3)0.003 (3)0.006 (3)
C20.023 (4)0.025 (4)0.018 (4)0.003 (3)0.006 (3)0.012 (3)
O110.108 (9)0.093 (7)0.119 (9)0.082 (7)0.093 (8)0.086 (7)
Geometric parameters (Å, °) top
Er1—O12.269 (5)S1—O41.442 (6)
Er1—O3i2.287 (5)S1—O61.449 (7)
Er1—O82.287 (5)S1—O51.460 (6)
Er1—O92.334 (5)S1—C21.777 (8)
Er1—O7ii2.354 (5)P1—O11.509 (5)
Er1—O102.394 (6)P1—O21.535 (5)
Er1—O3iii2.450 (5)P1—O31.547 (5)
Er1—O2iii2.475 (5)P1—C11.784 (8)
Er1—P1iii3.1010 (18)P1—Er1iii3.1010 (18)
Er1—Er23.5662 (5)O2—Er2vi2.242 (4)
Er1—Er2iv3.7884 (6)O2—Er1iii2.475 (5)
Er1—Er2ii3.8428 (6)O3—Er1vii2.287 (5)
Er2—O2v2.242 (5)O3—Er1iii2.450 (5)
Er2—O8ii2.299 (5)O5—Er2vi2.353 (5)
Er2—O72.317 (5)O7—Er1ii2.354 (5)
Er2—O92.319 (5)O7—Er2ii2.416 (5)
Er2—O9iv2.329 (5)O8—Er2ii2.299 (5)
Er2—O5v2.353 (5)O9—Er2iv2.329 (5)
Er2—O7ii2.416 (5)C1—C21.544 (10)
Er2—O82.716 (6)C1—H1A0.9700
Er2—Er2ii3.2420 (8)C1—H1B0.9700
Er2—Er2iv3.7479 (7)C2—H2A0.9700
Er2—Er1iv3.7884 (6)C2—H2B0.9700
O1—Er1—O3i101.48 (18)O7—Er2—O867.01 (16)
O1—Er1—O8150.13 (18)O9—Er2—O870.88 (16)
O3i—Er1—O899.53 (19)O9iv—Er2—O876.51 (16)
O1—Er1—O987.87 (18)O5v—Er2—O8126.96 (17)
O3i—Er1—O9160.71 (18)O7ii—Er2—O854.15 (16)
O8—Er1—O978.90 (19)O2v—Er2—Er2ii148.76 (13)
O1—Er1—O7ii141.65 (18)O8ii—Er2—Er2ii55.60 (15)
O3i—Er1—O7ii85.63 (17)O7—Er2—Er2ii48.05 (12)
O8—Er1—O7ii60.84 (17)O9—Er2—Er2ii108.32 (12)
O9—Er1—O7ii76.79 (17)O9iv—Er2—Er2ii109.66 (12)
O1—Er1—O1070.82 (19)O5v—Er2—Er2ii112.02 (14)
O3i—Er1—O1086.1 (2)O7ii—Er2—Er2ii45.52 (12)
O8—Er1—O10131.87 (19)O8—Er2—Er2ii44.30 (11)
O9—Er1—O1081.02 (19)O2v—Er2—Er1142.54 (13)
O7ii—Er1—O1072.17 (18)O8ii—Er2—Er1112.98 (13)
O1—Er1—O3iii80.62 (18)O7—Er2—Er1105.98 (12)
O3i—Er1—O3iii69.78 (19)O9—Er2—Er140.13 (11)
O8—Er1—O3iii87.03 (18)O9iv—Er2—Er190.81 (11)
O9—Er1—O3iii128.90 (16)O5v—Er2—Er190.97 (14)
O7ii—Er1—O3iii135.88 (18)O7ii—Er2—Er140.96 (11)
O10—Er1—O3iii137.99 (18)O8—Er2—Er139.89 (10)
O1—Er1—O2iii76.65 (17)Er2ii—Er2—Er168.536 (15)
O3i—Er1—O2iii128.23 (17)O2v—Er2—Er2iv88.10 (13)
O8—Er1—O2iii73.69 (17)O8ii—Er2—Er2iv168.52 (15)
O9—Er1—O2iii70.13 (16)O7—Er2—Er2iv108.96 (12)
O7ii—Er1—O2iii127.72 (16)O9—Er2—Er2iv36.36 (11)
O10—Er1—O2iii136.9 (2)O9iv—Er2—Er2iv36.18 (12)
O3iii—Er1—O2iii58.77 (15)O5v—Er2—Er2iv110.34 (15)
O1—Er1—P1iii76.23 (14)O7ii—Er2—Er2iv103.29 (11)
O3i—Er1—P1iii99.19 (13)O8—Er2—Er2iv69.65 (11)
O8—Er1—P1iii79.66 (13)Er2ii—Er2—Er2iv113.801 (19)
O9—Er1—P1iii99.42 (12)Er1—Er2—Er2iv62.333 (12)
O7ii—Er1—P1iii140.41 (12)O2v—Er2—Er1iv38.73 (13)
O10—Er1—P1iii147.01 (15)O8ii—Er2—Er1iv127.02 (12)
O3iii—Er1—P1iii29.49 (11)O7—Er2—Er1iv93.57 (12)
O2iii—Er1—P1iii29.30 (11)O9—Er2—Er1iv85.59 (11)
O1—Er1—Er2126.95 (13)O9iv—Er2—Er1iv35.72 (12)
O3i—Er1—Er2126.08 (13)O5v—Er2—Er1iv109.15 (14)
O8—Er1—Er249.59 (14)O7ii—Er2—Er1iv159.77 (11)
O9—Er1—Er239.82 (12)O8—Er2—Er1iv112.23 (11)
O7ii—Er1—Er242.28 (11)Er2ii—Er2—Er1iv138.048 (15)
O10—Er1—Er288.68 (14)Er1—Er2—Er1iv118.815 (12)
O3iii—Er1—Er2133.33 (11)Er2iv—Er2—Er1iv56.483 (10)
O2iii—Er1—Er288.92 (10)O4—S1—O6114.3 (4)
P1iii—Er1—Er2112.89 (3)O4—S1—O5110.4 (4)
O1—Er1—Er2iv81.22 (13)O6—S1—O5111.1 (4)
O3i—Er1—Er2iv161.90 (13)O4—S1—C2106.3 (4)
O8—Er1—Er2iv72.40 (14)O6—S1—C2107.4 (4)
O9—Er1—Er2iv35.63 (12)O5—S1—C2106.9 (4)
O7ii—Er1—Er2iv103.46 (11)O1—P1—O2112.9 (3)
O10—Er1—Er2iv111.42 (16)O1—P1—O3116.1 (3)
O3iii—Er1—Er2iv93.28 (11)O2—P1—O3103.3 (3)
O2iii—Er1—Er2iv34.51 (11)O1—P1—C1108.1 (4)
P1iii—Er1—Er2iv63.81 (3)O2—P1—C1110.6 (3)
Er2—Er1—Er2iv61.185 (12)O3—P1—C1105.5 (3)
O1—Er1—Er2ii175.89 (14)O1—P1—Er1iii130.4 (2)
O3i—Er1—Er2ii78.19 (13)O2—P1—Er1iii52.12 (18)
O8—Er1—Er2ii33.17 (13)O3—P1—Er1iii51.2 (2)
O9—Er1—Er2ii91.27 (12)C1—P1—Er1iii121.5 (3)
O7ii—Er1—Er2ii34.35 (12)P1—O1—Er1153.3 (3)
O10—Er1—Er2ii105.08 (14)P1—O2—Er2vi154.7 (3)
O3iii—Er1—Er2ii103.01 (12)P1—O2—Er1iii98.6 (2)
O2iii—Er1—Er2ii106.83 (11)Er2vi—O2—Er1iii106.76 (19)
P1iii—Er1—Er2ii107.88 (4)P1—O3—Er1vii150.2 (3)
Er2—Er1—Er2ii51.734 (13)P1—O3—Er1iii99.3 (2)
Er2iv—Er1—Er2ii100.378 (12)Er1vii—O3—Er1iii110.22 (19)
O2v—Er2—O8ii100.04 (19)S1—O5—Er2vi136.5 (3)
O2v—Er2—O7105.14 (17)Er2—O7—Er1ii110.7 (2)
O8ii—Er2—O761.23 (18)Er2—O7—Er2ii86.43 (16)
O2v—Er2—O9102.46 (17)Er1ii—O7—Er2ii96.76 (17)
O8ii—Er2—O9146.13 (16)Er1—O8—Er2ii113.9 (2)
O7—Er2—O9133.96 (17)Er1—O8—Er290.51 (19)
O2v—Er2—O9iv74.44 (17)Er2ii—O8—Er280.09 (15)
O8ii—Er2—O9iv138.60 (17)Er2—O9—Er2iv107.46 (18)
O7—Er2—O9iv80.31 (17)Er2—O9—Er1100.05 (18)
O9—Er2—O9iv72.54 (18)Er2iv—O9—Er1108.64 (19)
O2v—Er2—O5v77.68 (19)C2—C1—P1117.8 (6)
O8ii—Er2—O5v79.5 (2)C2—C1—H1A107.9
O7—Er2—O5v140.67 (19)P1—C1—H1A107.9
O9—Er2—O5v80.92 (19)C2—C1—H1B107.9
O9iv—Er2—O5v135.8 (2)P1—C1—H1B107.9
O2v—Er2—O7ii153.74 (18)H1A—C1—H1B107.2
O8ii—Er2—O7ii72.76 (17)C1—C2—S1115.0 (6)
O7—Er2—O7ii93.57 (16)C1—C2—H2A108.5
O9—Er2—O7ii75.87 (16)S1—C2—H2A108.5
O9iv—Er2—O7ii127.80 (16)C1—C2—H2B108.5
O5v—Er2—O7ii76.18 (18)S1—C2—H2B108.5
O2v—Er2—O8150.83 (16)H2A—C2—H2B107.5
O8ii—Er2—O899.91 (16)
Symmetry codes: (i) x−1, y, z; (ii) −x, −y+2, −z+1; (iii) −x+1, −y+1, −z+1; (iv) −x+1, −y+2, −z+1; (v) x, y+1, z; (vi) x, y−1, z; (vii) x+1, y, z.
Acknowledgements top

The authors thank PD Dr Christian Näther for the acquisition of the single-crystal data. This work was supported by the DFG-Project STO 643/2-2.

references
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