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Acta Crystallogr Sect E Struct Rep Online. 2008 November 1; 64(Pt 11): i73.
Published online 2008 October 15. doi:  10.1107/S1600536808030328
PMCID: PMC2959510

catena-Poly[tetra­sodium [[cis-dioxido-trans-bis­(sulfato-κO)molybdate(VI)]-μ-sulfato-κ2 O:O′]]

Abstract

Single crystals of the title compound, {Na4[MoVIO2(SO4)3]}n, were grown from a melt of MoO3 and Na2SO4 in Na2S2O7. In contrast to the structure of the isoformular K compound, K4[MoVIO2(SO4)3], with its monomeric anion, this sodium analogue contains a polymeric anion of the type {[MoVIO2(SO4)2-μ-(SO4)]4−}n. The MoVI cations, surrounded by two tightly bonded O atoms and four O atoms of one bridging and two terminal sulfato ligands, form zigzag chains parallel to [100]. All four Na+ cations are situated between the anionic chains and have distorted octa­hedral coordination spheres.

Related literature

The structure of the title isoformular potassium compound, K4[MoVIO2(SO4)3], was determined by Schäffer & Berg (2008 [triangle]). For related Mo-containing compounds, see Salles et al. (1996 [triangle]) and Nørbygaard et al. (1998 [triangle]). Related compounds with Mo replaced by W were discussed by Schäffer & Berg (2005 [triangle]) and Berg et al. (2006 [triangle]). Other sulfato complexes coordinated to late transition metal centers were reported by Berg & Thorup (2005 [triangle]), Borup et al. (1990 [triangle]), Nielsen et al. (1993 [triangle]) and Rasmussen et al. (2003 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-64-00i73-scheme1.jpg

Experimental

Crystal data

  • Na4[MoO2(SO4)3]
  • M r = 508.08
  • Orthorhombic, An external file that holds a picture, illustration, etc.
Object name is e-64-00i73-efi1.jpg
  • a = 8.4739 (6) Å
  • b = 9.2892 (7) Å
  • c = 15.1046 (11) Å
  • V = 1188.97 (15) Å3
  • Z = 4
  • Mo Kα radiation
  • μ = 1.85 mm−1
  • T = 120 (2) K
  • 0.24 × 0.18 × 0.02 mm

Data collection

  • Bruker SMART APEX CCD diffractometer
  • Absorption correction: gaussian (SHELXTL; Sheldrick, 2008 [triangle]) T min = 0.665, T max = 0.964
  • 14125 measured reflections
  • 2861 independent reflections
  • 2817 reflections with I > 2σ(I)
  • R int = 0.031

Refinement

  • R[F 2 > 2σ(F 2)] = 0.017
  • wR(F 2) = 0.042
  • S = 1.10
  • 2861 reflections
  • 199 parameters
  • Δρmax = 0.51 e Å−3
  • Δρmin = −0.26 e Å−3
  • Absolute structure: Flack (1983 [triangle]), 1205 Friedel pairs
  • Flack parameter: 0.01 (2)

Data collection: SMART (Bruker, 2002 [triangle]); cell refinement: SAINT (Bruker, 2002 [triangle]); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.

Table 1
Selected bond lengths (Å)

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536808030328/wm2186sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536808030328/wm2186Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Acknowledgments

The authors thank Astrid Schøneberg and Bodil Holten for their help and advice.

supplementary crystallographic information

Comment

Considerable amounts of molybdenum(VI) oxide, a solid well known for its insolubility in many acids, can be dissolved in sulfate melts at high temperatures, as was previously found for the chemically related tungsten(VI) oxide (Schäffer & Berg, 2005, Berg et al., 2006). When varying molar amounts of MoO3, Na2SO4, and hygroscopic Na2S2O7 are placed in ampoules in a dry box, sealed, and heated to equilibration in a rocking furnace at 773 K for ca. 1 h, the resulting clear melts contain [MoO2]2+ moieties that are bonded to SO42- units. The compositions of the reaction products have been determined to be in the stoichiometric ratio 1:1:1, or MoO3 + M2SO4 + M2S2O7M4[Mo(SO4)3O2]. In the case where M = K, a monomeric anion is formed (Schäffer & Berg, 2008), while for M = Na the anion is in a polymeric form.

The distorted octahedral coordination sphere of the MoVI cation contains two oxido ligands (cis), two terminally bound sulfato ligands (trans), and two O atoms of symmetry-related (x + 1/2, -y + 1/2, -z + 1) bridging sulfato ligands (cis), with O–Mo–O angles between any two cis oxygen atoms deviating as much as 15° from ideal values. The Mo–O bond distances to the tightly- bonded oxido ligands are similar (1.6905 (16) Å, 1.7108 (16) Å), which is expected as both bonds are trans to oxygen atoms in the bridging sulfato ligands. The Mo–O distances to the terminal sulfato ligands (Mo1–O4 and Mo1–O5) are slightly shorter than those to the brigding sulfato ligands, Mo1–03 and Mo1–O6A. The Mo–O distances compare well with previously reported values for related structures (Salles et al., 1996; Nørbygaard et al., 1998; Schäffer & Berg, 2008).

The coordination geometry of the sulfato ligands can be described as slightly distorted from tetrahedral, with angles ranging from 103.55 (9) to 113.77 (10)°. From the shortest to the longest, the S–O bond distances vary by type: S to terminal O atoms, 1.4516 (17)–1.4681 (17) Å; S to briding O atoms, 1.4941 (16) Å and 1.4953 (16) Å; S in the terminal sulfato ligands to the coordinating O atoms, 1.5589 (17) Å and 1.5346 (16) Å. This variation is typical for sulfato complexes of many different transition metal centers (Borup et al., 1990; Nielsen et al., 1993; Rasmussen et al., 2003, and Berg & Thorup, 2005).

All four sodium cations are situated between the anionic chains and are six-coordinate with Na–O bond distances ranging from 2.2713 (18) to 2.7652 (18) Å.

Experimental

Crystals were grown from a melt of equimolar amounts of MoO3, Na2SO4, and Na2S2O7, using a method described previously (Nørbygaard et al., 1998).

Refinement

On the basis of 1205 unmerged Friedel opposites, the fractional contribrution of the racemic twin was negligible (Flack, 1983). The two highest peaks in the final difference Fourier map were, respectively, 0.78 Å and 0.79 Å from Mo1, and the deepest hole was 1.31 Å from S2.

Figures

Fig. 1.
Plot of the asymmetric unit of Na4[MoVI(SO4)3O2], showing atoms as ellipsoids at the 50% probability level. [Symmetry code A) x+0.5, -y+0.5, -z+1.]
Fig. 2.
The crystal packing of Na4[MoVI(SO4)3O2], viewed along the b axis, showing the chains (thick black lines). Ellipsoids are displayed at the 50% probability level.

Crystal data

Na4[Mo(SO4)3O2]F(000) = 984
Mr = 508.08Dx = 2.838 Mg m3
Orthorhombic, P212121Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2abCell parameters from 5457 reflections
a = 8.4739 (6) Åθ = 2.6–27.9°
b = 9.2892 (7) ŵ = 1.86 mm1
c = 15.1046 (11) ÅT = 120 K
V = 1188.97 (15) Å3Tabular, colorless
Z = 40.24 × 0.18 × 0.02 mm

Data collection

Bruker SMART APEX CCD diffractometer2861 independent reflections
Radiation source: normal-focus sealed tube2817 reflections with I > 2σ(I)
graphiteRint = 0.031
ω scansθmax = 28.0°, θmin = 2.6°
Absorption correction: gaussian (SHELXTL; Sheldrick, 2008)h = −11→11
Tmin = 0.665, Tmax = 0.964k = −12→12
14125 measured reflectionsl = −19→19

Refinement

Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.017w = 1/[σ2(Fo2) + (0.0214P)2 + 0.3747P] where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.042(Δ/σ)max = 0.001
S = 1.10Δρmax = 0.51 e Å3
2861 reflectionsΔρmin = −0.26 e Å3
199 parametersAbsolute structure: Flack (1983), 1205 Friedel pairs
0 restraintsFlack parameter: 0.01 (2)

Special details

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. Five frame series were filtered for statistical outliers then corrected for absorption by integration using SHELXTL/XPREP (Bruker, 2001) before using SAINT/SADABS (Bruker, 2002) to sort, merge, and scale the combined data. A series of identical frames was collected twice during the experiment to monitor decay. No decay correction was applied. The systematic conditions suggested the uambiguous space group. The structure was solved by direct methods (Sheldrick, 2001). The final space group choice was confirmed by successful convergence of the full-matrix least-squares refinement on F2. An extinction correction was not applied. The two highest peaks in the final difference Fourier map were, repectively, 0.78Å and 0.79Å from Mo1; the deepest hole was 1.31Å from S2. The final map had no other significant features. A final analysis of variance between observed and calculated structure factors showed no dependence on amplitude or resolution.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2)

xyzUiso*/Ueq
Mo10.77389 (2)0.108886 (19)0.426923 (11)0.00683 (5)
S10.42167 (6)0.29669 (6)0.38157 (3)0.00770 (11)
S20.52730 (7)−0.14389 (6)0.48393 (3)0.00870 (11)
S30.87553 (6)0.37753 (6)0.29746 (3)0.00819 (10)
Na10.20072 (11)0.58268 (10)0.34042 (6)0.01293 (19)
Na20.80653 (11)0.75841 (10)0.31656 (6)0.01239 (19)
Na30.67303 (11)0.51270 (10)0.46834 (6)0.0144 (2)
Na40.57005 (11)0.46216 (10)0.21305 (6)0.01274 (19)
O10.70335 (19)0.03236 (17)0.33180 (10)0.0107 (3)
O20.94651 (19)0.02131 (17)0.44263 (11)0.0119 (3)
O30.57359 (18)0.25797 (17)0.42577 (11)0.0107 (3)
O40.6456 (2)−0.02040 (17)0.50576 (10)0.0116 (3)
O50.88450 (19)0.28237 (18)0.38036 (10)0.0120 (3)
O60.29354 (19)0.27689 (17)0.44854 (9)0.0096 (3)
O70.3902 (2)0.20606 (18)0.30489 (10)0.0123 (3)
O80.4313 (2)0.44896 (18)0.35609 (11)0.0124 (3)
O90.49519 (19)−0.20813 (17)0.56967 (11)0.0130 (3)
O100.60611 (19)−0.24259 (18)0.42327 (12)0.0147 (3)
O110.38958 (19)−0.07781 (18)0.44282 (11)0.0139 (3)
O120.7888 (2)0.29908 (17)0.22934 (10)0.0124 (3)
O130.7899 (2)0.50790 (17)0.32281 (10)0.0126 (3)
O141.03833 (19)0.40786 (18)0.27218 (10)0.0133 (3)

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
Mo10.00576 (8)0.00737 (9)0.00738 (8)0.00034 (7)−0.00028 (6)−0.00021 (7)
S10.0056 (2)0.0096 (3)0.0078 (2)0.0014 (2)−0.00017 (19)−0.0001 (2)
S20.0073 (2)0.0093 (2)0.0095 (2)−0.0009 (2)0.0006 (2)−0.00087 (19)
S30.0073 (2)0.0087 (2)0.0086 (2)−0.0001 (2)0.00067 (18)0.0004 (2)
Na10.0125 (5)0.0130 (5)0.0133 (4)0.0022 (4)0.0012 (3)0.0019 (3)
Na20.0111 (5)0.0126 (4)0.0135 (4)0.0012 (4)0.0018 (4)0.0017 (3)
Na30.0123 (4)0.0166 (5)0.0145 (5)−0.0034 (4)0.0023 (4)−0.0024 (4)
Na40.0107 (4)0.0156 (5)0.0120 (4)0.0010 (4)−0.0008 (4)0.0020 (4)
O10.0097 (8)0.0119 (8)0.0104 (7)0.0002 (6)−0.0002 (6)−0.0008 (6)
O20.0113 (8)0.0112 (8)0.0130 (8)0.0020 (6)−0.0021 (6)−0.0007 (6)
O30.0086 (7)0.0128 (7)0.0107 (7)0.0044 (6)−0.0029 (7)−0.0008 (7)
O40.0138 (8)0.0116 (8)0.0095 (7)−0.0053 (7)−0.0018 (6)0.0001 (6)
O50.0116 (8)0.0121 (8)0.0122 (8)−0.0036 (6)−0.0020 (6)0.0042 (6)
O60.0080 (7)0.0110 (7)0.0098 (7)−0.0010 (6)0.0006 (6)−0.0012 (6)
O70.0116 (8)0.0162 (9)0.0092 (7)0.0016 (7)−0.0016 (6)−0.0028 (6)
O80.0121 (8)0.0111 (8)0.0140 (8)0.0018 (7)0.0023 (7)0.0023 (6)
O90.0141 (8)0.0131 (8)0.0119 (7)−0.0042 (6)−0.0001 (7)0.0028 (7)
O100.0151 (8)0.0119 (8)0.0171 (8)−0.0010 (7)0.0051 (7)−0.0045 (7)
O110.0093 (8)0.0190 (9)0.0133 (8)0.0021 (7)−0.0016 (6)0.0017 (6)
O120.0141 (8)0.0120 (8)0.0109 (7)−0.0002 (7)−0.0015 (6)−0.0011 (6)
O130.0106 (8)0.0108 (8)0.0163 (8)0.0025 (7)−0.0008 (7)−0.0015 (6)
O140.0095 (8)0.0167 (9)0.0136 (7)−0.0012 (7)0.0042 (6)0.0008 (7)

Geometric parameters (Å, °)

Mo1—O21.6905 (16)Na1—O9iv2.4972 (19)
Mo1—O11.7108 (16)Na1—O1ii2.7652 (18)
Mo1—O51.9925 (16)Na2—O132.3333 (18)
Mo1—O42.0102 (16)Na2—O14v2.3350 (19)
Mo1—O6i2.1661 (15)Na2—O10vi2.3415 (19)
Mo1—O32.1907 (15)Na2—O9i2.3932 (19)
S1—O71.4564 (16)Na2—O7ii2.5262 (18)
S1—O81.4681 (17)Na2—O1vi2.7006 (19)
S1—O31.4941 (16)Na2—S3v3.3837 (11)
S1—O61.4953 (16)Na3—O11i2.3524 (19)
S2—O91.4516 (17)Na3—O2iv2.3649 (19)
S2—O111.4575 (17)Na3—O132.4115 (18)
S2—O101.4581 (17)Na3—O10vi2.4398 (19)
S2—O41.5589 (17)Na3—O32.5928 (19)
S3—O141.4590 (17)Na3—O82.724 (2)
S3—O121.4595 (16)Na4—O7ii2.3065 (19)
S3—O131.4627 (16)Na4—O122.407 (2)
S3—O51.5346 (16)Na4—O11ii2.4078 (19)
Na1—O12ii2.2713 (18)Na4—O82.4629 (19)
Na1—O82.3273 (19)Na4—O1ii2.5003 (19)
Na1—O14iii2.3649 (19)Na4—O132.5297 (19)
Na1—O4iv2.4394 (18)
O2—Mo1—O1102.72 (8)O11i—Na3—O3129.03 (7)
O2—Mo1—O591.81 (7)O2iv—Na3—O375.84 (6)
O1—Mo1—O5101.77 (7)O13—Na3—O383.71 (6)
O2—Mo1—O495.58 (7)O10vi—Na3—O3134.87 (6)
O1—Mo1—O493.46 (7)O11i—Na3—O8175.92 (7)
O5—Mo1—O4161.18 (7)O2iv—Na3—O873.41 (6)
O2—Mo1—O6i92.71 (7)O13—Na3—O874.78 (6)
O1—Mo1—O6i163.68 (7)O10vi—Na3—O881.61 (6)
O5—Mo1—O6i82.77 (6)O3—Na3—O853.34 (5)
O4—Mo1—O6i79.62 (6)O7ii—Na4—O12121.20 (7)
O2—Mo1—O3167.36 (7)O7ii—Na4—O11ii90.91 (6)
O1—Mo1—O389.16 (7)O12—Na4—O11ii83.88 (6)
O5—Mo1—O381.39 (6)O7ii—Na4—O8102.80 (7)
O4—Mo1—O387.91 (6)O12—Na4—O8104.28 (6)
O6i—Mo1—O375.92 (6)O11ii—Na4—O8156.62 (7)
O7—S1—O8111.01 (10)O7ii—Na4—O1ii81.21 (6)
O7—S1—O3111.95 (9)O12—Na4—O1ii154.90 (7)
O8—S1—O3107.53 (10)O11ii—Na4—O1ii84.66 (6)
O7—S1—O6109.52 (9)O8—Na4—O1ii78.95 (6)
O8—S1—O6109.65 (10)O7ii—Na4—O1378.73 (6)
O3—S1—O6107.08 (9)O12—Na4—O1358.10 (6)
O9—S2—O11113.77 (10)O11ii—Na4—O13124.20 (7)
O9—S2—O10112.83 (10)O8—Na4—O1377.59 (6)
O11—S2—O10111.33 (10)O1ii—Na4—O13144.70 (7)
O9—S2—O4103.55 (9)Mo1—O1—Na4vii131.27 (9)
O11—S2—O4107.18 (10)Mo1—O1—Na2viii110.49 (7)
O10—S2—O4107.52 (10)Na4vii—O1—Na2viii91.78 (6)
O14—S3—O12112.83 (10)Mo1—O1—Na1vii128.10 (8)
O14—S3—O13112.19 (10)Na4vii—O1—Na1vii93.53 (5)
O12—S3—O13110.37 (10)Na2viii—O1—Na1vii89.08 (5)
O14—S3—O5106.14 (9)Mo1—O2—Na3i147.82 (9)
O12—S3—O5108.22 (9)S1—O3—Mo1145.42 (10)
O13—S3—O5106.73 (10)S1—O3—Na399.86 (8)
O12ii—Na1—O8119.12 (7)Mo1—O3—Na3108.85 (6)
O12ii—Na1—O14iii115.36 (7)S2—O4—Mo1131.46 (9)
O8—Na1—O14iii99.58 (7)S2—O4—Na1i98.63 (8)
O12ii—Na1—O4iv131.24 (7)Mo1—O4—Na1i127.05 (8)
O8—Na1—O4iv86.40 (6)S3—O5—Mo1136.93 (10)
O14iii—Na1—O4iv98.10 (6)S1—O6—Mo1iv125.67 (9)
O12ii—Na1—O9iv82.33 (6)S1—O7—Na4vii129.39 (10)
O8—Na1—O9iv141.19 (7)S1—O7—Na2vii125.94 (10)
O14iii—Na1—O9iv98.72 (7)Na4vii—O7—Na2vii101.54 (7)
O4iv—Na1—O9iv57.26 (6)S1—O8—Na1119.62 (10)
O12ii—Na1—O1ii72.64 (6)S1—O8—Na4107.73 (9)
O8—Na1—O1ii76.04 (6)Na1—O8—Na4106.56 (7)
O14iii—Na1—O1ii69.21 (5)S1—O8—Na395.05 (8)
O4iv—Na1—O1ii155.81 (6)Na1—O8—Na3125.35 (7)
O9iv—Na1—O1ii142.71 (6)Na4—O8—Na3100.15 (7)
O13—Na2—O14v130.56 (7)S2—O9—Na2iv147.79 (11)
O13—Na2—O10vi85.66 (6)S2—O9—Na1i99.36 (8)
O14v—Na2—O10vi143.70 (7)Na2iv—O9—Na1i99.58 (7)
O13—Na2—O9i79.43 (6)S2—O10—Na2viii139.66 (10)
O14v—Na2—O9i98.75 (7)S2—O10—Na3viii121.13 (10)
O10vi—Na2—O9i89.40 (7)Na2viii—O10—Na3viii91.56 (6)
O13—Na2—O7ii78.32 (6)S2—O11—Na3iv119.33 (9)
O14v—Na2—O7ii93.97 (6)S2—O11—Na4vii111.58 (9)
O10vi—Na2—O7ii91.17 (7)Na3iv—O11—Na4vii128.97 (8)
O9i—Na2—O7ii157.64 (7)S3—O12—Na1vii138.53 (11)
O13—Na2—O1vi156.46 (7)S3—O12—Na498.37 (8)
O14v—Na2—O1vi70.79 (6)Na1vii—O12—Na4122.67 (8)
O10vi—Na2—O1vi73.15 (6)S3—O13—Na2141.74 (10)
O9i—Na2—O1vi109.81 (6)S3—O13—Na3117.23 (9)
O7ii—Na2—O1vi91.70 (6)Na2—O13—Na392.48 (6)
O11i—Na3—O2iv110.07 (7)S3—O13—Na493.14 (8)
O11i—Na3—O13101.80 (6)Na2—O13—Na4100.69 (7)
O2iv—Na3—O13148.13 (7)Na3—O13—Na4107.34 (7)
O11i—Na3—O10vi95.79 (7)S3—O14—Na2ix124.60 (10)
O2iv—Na3—O10vi95.42 (7)S3—O14—Na1x124.66 (10)
O13—Na3—O10vi81.85 (6)Na2ix—O14—Na1x109.32 (7)

Symmetry codes: (i) x+1/2, −y+1/2, −z+1; (ii) −x+1, y+1/2, −z+1/2; (iii) x−1, y, z; (iv) x−1/2, −y+1/2, −z+1; (v) −x+2, y+1/2, −z+1/2; (vi) x, y+1, z; (vii) −x+1, y−1/2, −z+1/2; (viii) x, y−1, z; (ix) −x+2, y−1/2, −z+1/2; (x) x+1, y, z.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: WM2186).

References

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