metal-organic compounds
(C3H12N2)2[UO2(H2O)2(SO4)2]2·2H2O: an organically templated uranium sulfate with a novel dimer type
aChemistry Research Laboratory, University of Oxford, Mansfield Road, Oxford OX1 3TA, England, and bDepartment of Chemistry, Haverford College, 370 Lancaster Avenue, Haverford, PA 19041, USA
*Correspondence e-mail: dermot.ohare@chem.ox.ac.uk
The title compound, bis(propane-1,2-diaminium) tetraaquadi-μ2-sulfato-disulfatotetraoxodiuranate(VI) dihydrate, (C3H12N2)2[U2O4(SO4)4(H2O)4]·2H2O, contains discrete centrosymmetric anionic {[UO2(H2O)2(SO4)2]2}4− dimers with C3H12N22+ cations balancing the charge. The dimers form hydrogen-bonded layers. The cations and occluded water molecules participate in an extensive hydrogen-bonding network. Each UVI centre is seven-coordinate with a pentagonal–bipyramidal geometry. Both pendent and bridging sulfate tetrahedra are observed, as well as bound and occluded water molecules.
Comment
Hydrothermal synthesis is a well established method for the formation of inorganic structures templated by organic ions. The majority of these compounds are metal phosphates (Cheetham et al., 1999), with other examples including metal phosphites (Doran et al., 2001; Fernandez et al., 2002), fluorides (Walker et al., 1999), germanates (Reisner et al., 2001; Bu et al., 1998; Conradsson et al., 2000), arsenates (Ekambaram & Sevov, 2000; Bazan et al., 2000), oxalates (Vaidhyanathan et al., 2002) and selenites (Choudhury et al., 2002; Harrison et al., 2000).
A recently employed strategy for the design of new inorganic architectures involves the use of the sulfate tetrahedron as a primary substituent. Compounds incorporating U (Doran et al., 2002, 2003a,b,c,d; Doran, Norquist et al., 2004; Doran, Cockbain et al., 2004; Norquist et al., 2002, 2003a,b; Norquist et al., 2003; Thomas et al., 2003; Stuart et al., 2003), Cd (Choudhury et al., 2001; Paul et al., 2002b), La (Bataille & Louer, 2002; Xing, Liu et al., 2003; Xing Shi et al., 2003), Ce (Wang et al., 2002), Sc (Bull et al., 2002), Fe (Paul, Choudhury & Rao, 2002a, 2003; Paul et al., 2002), V (Paul, Choudhury, Nagarajan & Rao, 2003; Khan et al., 1999), Zn (Morimoto & Lingafelter, 1970) and Mo (Gutnick et al., 2004) are known. These compounds exhibit great structural diversity, with structures ranging from molecular anions to three-dimensional frameworks. This report contains the synthesis and structure of an organically templated uranium sulfate, [N2C3H12]2[UO2(H2O)2(SO4)2]2·2H2O, (I), designated USO-31 (uranium sulfate from Oxford).
A single independent U atom is present in USO-31. U1 is seven-coordinate (Fig. 1 and Table 1) in a pentagonal–bipyramidal geometry. Two short `uranyl' bonds to axial O atoms are observed, with U—O distances of 1.765 (3) Å and 1.772 (4) Å, close to the average reported value of 1.758 (3) Å (Burns et al., 1997). The O1—U1—O2 angle is close to 180°, with a value of 178.91 (16)°. Three of the five equatorial coordination sites around U1 are occupied by O atoms of sulfate groups, with U—O distances of 2.335 (3), 2.380 (3) and 2.385 (3) Å. The remaining two equatorial coordination sites are occupied by bound water molecules, with U—O distances of 2.420 (3) and 2.437 (3) Å. The assignment of the bound water molecules was based on the longer U—O bond lengths and hydrogen-bonding interactions. Two distinct sulfur sites are observed in USO-31. S1 and S2 are both at the centre of [SO4] tetrahedra. S1 tetrahedra link to one U centre and have three terminal O atoms, in contrast with S2 tetrahedra, which bridge between two U centres and have two terminal O atoms. The S—Obridging distances range between 1.490 (3) and 1.500 (3) Å. The S—Oterminal distances are shorter, ranging between 1.463 (4) and 1.475 (4) Å.
Centrosymmetric dimers are formed as a result of the connectivities between the [UO7] and [SO4] polyhedra. This dimer topology is, to the best of our knowledge, previously unknown in uranium chemistry. It is related to the [(UO2)2(SO4)6]8− dimers in USO-10 (Norquist et al., 2003a) and USO-12 (Norquist et al., 2003b), which contain edge-shared sulfate groups in place of the bound water molecules of USO-31. Hydrogen-bonded layers are formed (see Fig. 2), because the four bound water molecules of each dimer donate hydrogen bonds to the terminal sulfate O atoms of adjacent dimers. These pseudo-layers propagate in the (010) plane and are separated by template cations and occluded water molecules (see Fig. 3). The interlayer species are involved in hydrogen bonding with the layer (Table 2).
Experimental
UO2(CH3CO2)2·2H2O (0.1062 g, 0.249 × 10−3 mol), H2SO4 (0.2623 g, 2.61 × 10−3 mol), 1,2-diaminopropane (0.1544 g, 2.05 × 10−3 mol), HF (0.1302 g, 2.59 × 10−3 mol, 40% aq.) and water (0.7443 g, 41.3 × 10−3 mol) were placed in a 23 ml Teflon-lined autoclave. The autoclave was heated to 453 K for 24 h, and then slowly cooled to 297 K over an additional period of 24 h. The autoclave was opened in air and the products recovered by filtration. A yield of 31%, based on uranium, was observed. The yield can be increased with slow evaporation of the post-reaction supernatant solution. Template N—H bending and stretching modes were observed at 1600 and 3100 cm−1 in the IR spectrum of USO-31. The C—H bend was measured at 1472 cm−1. A band centred at 1100 cm−1 corresponds to S—O stretches, with the asymmetric uranyl stretch at 936 cm−1. Analysis found: N 4.90, C 6.26, H 3.15, S 11.19, U 38.21%; calculated: N 4.73, C 6.08, H 3.06, S 10.83, U 40.18%. The thermal stability of USO-31 was probed using thermogravimetric analysis. Weight losses between 373 and 403 K (2.7%), and 413 and 538 K (6.1%) result from the loss of occluded (calculated 3.0%) and bound water molecules (calculated 6.1%), respectively. A 16.5% weight loss was measured between 583 and 693 K, corresponding to template decomposition and the onset of breakdown of the inorganic moiety. The material calcines to UO2, determined using powder X-ray diffraction, by 1173 K, with a total mass loss of 55.0% (calculated 54.4%). Structural analysis was conducted at 150 K.
Crystal data
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Refinement
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H atoms were placed geometrically after each cycle in idealized locations at 1.00 Å from the Uiso(H) = 1.2Ueq (carrier atom) was applied in all cases. The highest peak is 0.96 Å from O1, and the deepest hole is 0.85 Å from U1.
such that plausible hydrogen-bonding interactions are made, and refined as riding. The constraintData collection: COLLECT (Nonius, 2001); cell DENZO/SCALEPACK (Otwinowski & Minor, 1997); data reduction: DENZO/SCALEPACK; program(s) used to solve structure: SIR92 (Altomare et al., 1993); program(s) used to refine structure: CRYSTALS (Betteridge et al., 2003); molecular graphics: ATOMS (Dowty, 2000); software used to prepare material for publication: CRYSTALS (Betteridge et al., 2003).
Supporting information
https://doi.org/10.1107/S1600536805009682/cv6473sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536805009682/cv6473Isup2.hkl
Data collection: COLLECT (Nonius, 2001); cell
DENZO/SCALEPACK (Otwinowski & Minor, 1997); data reduction: DENZO/SCALEPACK; program(s) used to solve structure: SIR92 (Altomare et al., 1993); program(s) used to refine structure: CRYSTALS (Betteridge et al., 2003); molecular graphics: ATOMS (Dowty, 2000); software used to prepare material for publication: CRYSTALS (Betteridge et al., 2003).(C3H12N2)2[U2O4(SO4)4(H2O)4]·2H2O | Z = 1 |
Mr = 1184.73 | F(000) = 556.000 |
Triclinic, P1 | Dx = 2.807 Mg m−3 |
Hall symbol: -P 1 | Melting point: not measured K |
a = 7.3983 (2) Å | Mo Kα radiation, λ = 0.71073 Å |
b = 7.6333 (2) Å | Cell parameters from 2953 reflections |
c = 12.5946 (5) Å | θ = 5–27° |
α = 95.1761 (12)° | µ = 11.95 mm−1 |
β = 94.6412 (13)° | T = 150 K |
γ = 96.578 (2)° | Plate, yellow |
V = 700.70 (4) Å3 | 0.10 × 0.06 × 0.01 mm |
Nonius KappaCCD diffractometer | 2820 reflections with I > 3u(I) |
Graphite monochromator | Rint = 0.02 |
ω scans | θmax = 27.4°, θmin = 5.4° |
Absorption correction: multi-scan (Otwinowski & Minor, 1997) | h = −8→9 |
Tmin = 0.46, Tmax = 0.89 | k = −9→9 |
5870 measured reflections | l = −16→16 |
3154 independent reflections |
Refinement on F2 | Hydrogen site location: inferred from neighbouring sites |
Least-squares matrix: full | H-atom parameters constrained |
R[F2 > 2σ(F2)] = 0.023 | Prince (1982) modified Chebychev polynomial with four parameters (Watkin, 1994), 11.1, 14.6, 7.77, 2.08 |
wR(F2) = 0.056 | (Δ/σ)max = 0.001 |
S = 0.83 | Δρmax = 1.22 e Å−3 |
2820 reflections | Δρmin = −1.39 e Å−3 |
191 parameters | Extinction correction: Larson (1970) |
Primary atom site location: structure-invariant direct methods | Extinction coefficient: 12.0 (11) |
x | y | z | Uiso*/Ueq | ||
H1 | 0.4926 | 0.9562 | 0.7360 | 0.0200* | |
H2 | 0.4688 | 0.8838 | 0.8573 | 0.0200* | |
H3 | 0.3216 | 0.7782 | 0.5899 | 0.0169* | |
H4 | 0.2260 | 0.9490 | 0.5713 | 0.0169* | |
H5 | 0.7946 | 1.4761 | 0.9702 | 0.0158* | |
H6 | 0.6236 | 1.3183 | 0.9617 | 0.0158* | |
H7 | 0.8328 | 1.2725 | 0.9840 | 0.0158* | |
H8 | 0.7950 | 1.4003 | 0.6341 | 0.0211* | |
H9 | 0.5882 | 1.4470 | 0.6040 | 0.0211* | |
H10 | 0.6208 | 1.2473 | 0.6315 | 0.0211* | |
H11 | 0.8955 | 1.3462 | 0.8126 | 0.0138* | |
H12 | 0.7246 | 1.1884 | 0.8040 | 0.0138* | |
H13 | 0.6912 | 1.5557 | 0.7874 | 0.0156* | |
H14 | 0.3772 | 1.4821 | 0.7399 | 0.0245* | |
H15 | 0.3931 | 1.2777 | 0.7645 | 0.0245* | |
H16 | 0.4326 | 1.4375 | 0.8619 | 0.0245* | |
H17 | 1.0886 | 1.4892 | 0.6554 | 0.0311* | |
H18 | 1.1066 | 1.3173 | 0.5699 | 0.0311* | |
N1 | 0.7531 (6) | 1.3485 (6) | 0.9457 (3) | 0.0129 | |
C3 | 0.4450 (7) | 1.4043 (8) | 0.7844 (5) | 0.0204 | |
C1 | 0.7655 (7) | 1.3164 (6) | 0.8276 (4) | 0.0115 | |
C2 | 0.6471 (7) | 1.4282 (6) | 0.7642 (4) | 0.0133 | |
N2 | 0.6642 (7) | 1.3764 (6) | 0.6490 (4) | 0.0178 | |
O1 | 0.0636 (5) | 1.0956 (5) | 0.7338 (3) | 0.0130 | |
O2 | 0.0987 (5) | 0.6631 (5) | 0.8066 (3) | 0.0165 | |
O3 | −0.1697 (5) | 0.7613 (5) | 0.6487 (3) | 0.0131 | |
O4 | −0.1830 (5) | 0.8925 (5) | 0.8680 (3) | 0.0118 | |
O5 | 0.1872 (5) | 0.9863 (5) | 0.9501 (3) | 0.0118 | |
O6 | 0.4115 (5) | 0.9355 (5) | 0.7946 (3) | 0.0164 | |
O7 | 0.2060 (5) | 0.8312 (5) | 0.6002 (3) | 0.0138 | |
O8 | −0.3691 (5) | 0.9913 (4) | 0.6361 (3) | 0.0129 | |
O9 | −0.4780 (5) | 0.6865 (5) | 0.5722 (3) | 0.0140 | |
O10 | −0.2593 (6) | 0.8546 (5) | 0.4764 (3) | 0.0183 | |
O11 | −0.4306 (5) | 0.7929 (5) | 0.9675 (3) | 0.0143 | |
O12 | −0.1290 (5) | 0.7093 (5) | 1.0132 (3) | 0.0135 | |
O13 | 1.0267 (6) | 1.4074 (6) | 0.5942 (3) | 0.0246 | |
U1 | 0.07888 (2) | 0.87952 (2) | 0.770225 (14) | 0.0086 | |
S1 | −0.32052 (15) | 0.82608 (15) | 0.58177 (9) | 0.0089 | |
S2 | −0.23260 (15) | 0.84808 (15) | 0.97579 (9) | 0.0081 |
U11 | U22 | U33 | U12 | U13 | U23 | |
N1 | 0.0119 (19) | 0.013 (2) | 0.014 (2) | 0.0007 (15) | 0.0033 (15) | 0.0043 (16) |
C3 | 0.013 (2) | 0.023 (3) | 0.025 (3) | 0.003 (2) | −0.001 (2) | 0.003 (2) |
C1 | 0.014 (2) | 0.008 (2) | 0.012 (2) | 0.0035 (17) | −0.0001 (17) | −0.0002 (17) |
C2 | 0.016 (2) | 0.010 (2) | 0.013 (2) | 0.0004 (18) | −0.0015 (18) | 0.0016 (17) |
N2 | 0.023 (2) | 0.016 (2) | 0.013 (2) | 0.0009 (17) | −0.0013 (17) | 0.0016 (16) |
O1 | 0.0101 (16) | 0.0144 (17) | 0.0154 (17) | 0.0006 (13) | 0.0024 (13) | 0.0059 (13) |
O2 | 0.0143 (17) | 0.0122 (17) | 0.0233 (19) | 0.0029 (13) | −0.0001 (14) | 0.0039 (14) |
O3 | 0.0085 (16) | 0.0141 (17) | 0.0168 (18) | 0.0037 (13) | −0.0014 (13) | 0.0020 (13) |
O4 | 0.0097 (16) | 0.0163 (17) | 0.0100 (16) | 0.0020 (13) | 0.0039 (12) | 0.0017 (13) |
O5 | 0.0089 (16) | 0.0126 (16) | 0.0130 (17) | 0.0013 (12) | −0.0003 (12) | −0.0021 (13) |
O6 | 0.0082 (16) | 0.028 (2) | 0.0132 (17) | 0.0038 (14) | −0.0002 (13) | 0.0038 (15) |
O7 | 0.0109 (16) | 0.0180 (17) | 0.0127 (17) | 0.0016 (13) | 0.0041 (13) | 0.0007 (14) |
O8 | 0.0110 (16) | 0.0101 (16) | 0.0184 (18) | 0.0042 (13) | 0.0043 (13) | −0.0005 (13) |
O9 | 0.0091 (16) | 0.0102 (16) | 0.0216 (19) | −0.0003 (13) | −0.0011 (13) | 0.0005 (14) |
O10 | 0.028 (2) | 0.0224 (19) | 0.0075 (17) | 0.0103 (16) | 0.0077 (15) | 0.0044 (14) |
O11 | 0.0054 (15) | 0.0216 (18) | 0.0149 (17) | −0.0030 (13) | 0.0001 (13) | 0.0039 (14) |
O12 | 0.0122 (16) | 0.0115 (16) | 0.0164 (18) | 0.0012 (13) | −0.0021 (13) | 0.0023 (13) |
O13 | 0.027 (2) | 0.025 (2) | 0.025 (2) | 0.0145 (17) | 0.0071 (17) | 0.0060 (17) |
U1 | 0.0068 (1) | 0.0095 (1) | 0.0095 (1) | 0.00108 (6) | 0.00123 (6) | 0.00091 (6) |
S1 | 0.0082 (5) | 0.0090 (5) | 0.0096 (5) | 0.0013 (4) | 0.0013 (4) | 0.0006 (4) |
S2 | 0.0063 (5) | 0.0104 (5) | 0.0074 (5) | 0.0002 (4) | 0.0010 (4) | 0.0003 (4) |
U1—O1 | 1.765 (3) | O6—H1 | 1.000 |
U1—O2 | 1.772 (4) | O6—H2 | 1.000 |
U1—O3 | 2.335 (3) | O7—H3 | 1.000 |
U1—O4 | 2.385 (3) | O7—H4 | 1.000 |
U1—O5 | 2.380 (3) | O13—H17 | 1.000 |
U1—O6 | 2.437 (3) | O13—H18 | 1.000 |
U1—O7 | 2.420 (3) | N1—H5 | 1.000 |
S1—O3 | 1.500 (3) | N1—H6 | 1.000 |
S1—O8 | 1.475 (3) | N1—H7 | 1.000 |
S1—O9 | 1.475 (4) | N2—H8 | 1.000 |
S1—O10 | 1.463 (4) | N2—H9 | 1.000 |
S2—O4 | 1.493 (4) | N2—H10 | 1.000 |
S2i—O5 | 1.490 (3) | C1—H11 | 1.000 |
S2—O11 | 1.470 (3) | C1—H12 | 1.000 |
S2—O12 | 1.466 (4) | C2—H13 | 1.000 |
N1—C1 | 1.498 (6) | C3—H14 | 1.000 |
N2—C2 | 1.489 (7) | C3—H15 | 1.000 |
C1—C2 | 1.520 (7) | C3—H16 | 1.000 |
C2—C3 | 1.530 (7) | ||
O1—U1—O2 | 178.91 (16) | N2—C2—C1 | 106.6 (4) |
O1—U1—O3 | 91.88 (14) | N2—C2—C3 | 109.1 (4) |
O1—U1—O4 | 90.74 (14) | C1—C2—C3 | 114.6 (4) |
O1—U1—O5 | 92.44 (14) | H1—O6—H2 | 114.895 |
O1—U1—O6 | 91.42 (14) | H1—O6—U1 | 125.07 |
O1—U1—O7 | 84.59 (15) | H2—O6—U1 | 114.75 |
O2—U1—O3 | 88.87 (15) | H3—O7—H4 | 104.304 |
O2—U1—O4 | 90.22 (15) | H3—O7—U1 | 124.91 |
O2—U1—O5 | 87.36 (15) | H4—O7—U1 | 107.01 |
O2—U1—O6 | 87.51 (15) | H17—O13—H18 | 111.243 |
O2—U1—O7 | 94.84 (15) | H5—N1—H6 | 109.476 |
O3—U1—O4 | 74.72 (12) | H5—N1—H7 | 109.476 |
O3—U1—O5 | 147.53 (12) | H6—N1—H7 | 109.476 |
O3—U1—O6 | 143.92 (12) | H5—N1—C1 | 109.5 |
O3—U1—O7 | 74.91 (12) | H6—N1—C1 | 109.4 |
O4—U1—O5 | 73.06 (12) | H7—N1—C1 | 109.5 |
O4—U1—O6 | 141.14 (12) | H14—C3—H15 | 109.476 |
O4—U1—O7 | 149.08 (12) | H14—C3—H16 | 109.476 |
O5—U1—O6 | 68.09 (12) | H15—C3—H16 | 109.476 |
O5—U1—O7 | 137.55 (12) | H14—C3—C2 | 109.5 |
O6—U1—O7 | 69.66 (12) | H15—C3—C2 | 109.4 |
O3—S1—O8 | 109.3 (2) | H16—C3—C2 | 109.5 |
O3—S1—O9 | 106.8 (2) | H11—C1—H12 | 109.467 |
O3—S1—O10 | 108.9 (2) | H11—C1—N1 | 108.8 |
O8—S1—O9 | 109.9 (2) | H12—C1—N1 | 108.8 |
O8—S1—O10 | 111.2 (2) | H11—C1—C2 | 108.8 |
O9—S1—O10 | 110.7 (2) | H12—C1—C2 | 108.8 |
O4—S2—O5i | 106.9 (2) | H13—C2—C3 | 105.4 |
O4—S2—O11 | 107.8 (2) | H13—C2—C1 | 107.9 |
O4—S2—O12 | 110.8 (2) | H13—C2—N2 | 113.5 |
O5i—S2—O11 | 109.6 (2) | H8—N2—H9 | 109.475 |
O5i—S2—O12 | 110.0 (2) | H8—N2—H10 | 109.476 |
O11—S2—O12 | 111.7 (2) | H9—N2—H10 | 109.476 |
U1—O3—S1 | 138.5 (2) | H8—N2—C2 | 109.5 |
U1—O4—S2 | 135.8 (2) | H9—N2—C2 | 109.4 |
U1—O5—S2i | 142.6 (2) | H10—N2—C2 | 109.5 |
N1—C1—C2 | 112.2 (4) |
Symmetry code: (i) −x, −y+2, −z+2. |
D—H···A | D—H | H···A | D···A | D—H···A |
O6—H1···O8ii | 1.00 | 1.71 | 2.705 (5) | 180 |
O6—H2···O11ii | 1.00 | 1.76 | 2.756 (5) | 180 |
O7—H3···O9ii | 1.00 | 1.73 | 2.732 (5) | 180 |
O7—H4···O10iii | 1.00 | 1.67 | 2.665 (5) | 180 |
N1—H5···O12iv | 1.00 | 1.82 | 2.824 (6) | 179 |
N1—H6···O11i | 1.00 | 1.90 | 2.846 (5) | 156 |
N1—H7···O12v | 1.00 | 2.18 | 2.878 (6) | 126 |
N2—H8···O13 | 1.00 | 1.82 | 2.812 (6) | 170 |
N2—H9···O9iv | 1.00 | 2.01 | 2.909 (6) | 148 |
N2—H10···O8ii | 1.00 | 1.97 | 2.911 (6) | 156 |
O13—H18···O10vi | 1.00 | 1.91 | 2.909 (5) | 180 |
Symmetry codes: (i) −x, −y+2, −z+2; (ii) x+1, y, z; (iii) −x, −y+2, −z+1; (iv) x+1, y+1, z; (v) −x+1, −y+2, −z+2; (vi) −x+1, −y+2, −z+1. |
Acknowledgements
The authors thank the Engineering and Physical Sciences Research Council (EPSRC) for funding.
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