Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S010827010000408X/ta1280sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S010827010000408X/ta1280Isup2.hkl |
A solution containing Na2WO4·2H2O (19.8 g, 0.060 mol) in water (75 ml) was adjusted to pH 4.8 with concentrated nitric acid, and a solution containing MnSO4·H2O (1.70 g, 0.010 mol; 20 ml) was added dropwise. The resulting pale yellow solution formed a yellow precipitate after about 10 min of stirring, which redissolved on heating. The solution was heated to boiling and solid Na2S2O8 (4.80 g, 0.020 mol) added with constant stirring. The solution slowly turned red-brown, indicating oxidation of MnII to MnIV. Boiling was continued until the evolution of oxygen ceased, by which time the solution was a dark red-brown colour. The solution was filtered while still hot and the filtrate placed in a 250 ml beaker, covered with a watchglass and allowed to remain undisturbed at room temperature. Over a period of several weeks MnO2 initially precipitated, and the solution was decanted several times. Eventually, red-brown crystals formed, which were filtered, washed with ice-cold water and dried (10.25 g, 50% yield). Spectroscopic analysis: UV-vis (water, pH 5.0): λmax 480 nm, ε 380 dm3 mol−1 cm−1; IR (KBr disk, cm−1): 912 s (W=O stretching), 863 s, 700 s (W—O—W, W—O—Mn stretching).
There appeared to be some positional disorder associated with the cation positions Na3 and Na4, based on residual peaks in the Fourier difference map, but attempts to locate separate atoms in reasonable locations failed to produce any further satisfactory refinement. The maximum peak and minimum trough were located close to the W atoms, but not in chemically significant positions. Data reduction used locally written programs (U·N·S·W.).
Data collection: Please specify; cell refinement: Please specify; data reduction: local software; program(s) used to solve structure: SHELXS86 (Sheldrick, 1990); program(s) used to refine structure: SHELXL93 (Sheldrick, 1993); molecular graphics: ORTEPII (Johnson, 1976).
Fig. 1. The anion in Na8[MnW6O24].18H2O indicating the atom-labelling scheme. Displacement ellipsoids are shown at the 50% probability level. |
Na8(MnW6O24)·18H2O | F(000) = 1858 |
Mr = 2050.22 | Dx = 3.487 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71069 Å |
a = 11.686 (12) Å | Cell parameters from 10 reflections |
b = 11.671 (6) Å | θ = 10–11° |
c = 16.667 (18) Å | µ = 18.09 mm−1 |
β = 120.80 (4)° | T = 293 K |
V = 1953 (3) Å3 | Plate, red-brown |
Z = 2 | 0.20 × 0.18 × 0.03 mm |
Enraf-Nonius CAD-4 diffractometer | 3017 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.000 |
Graphite monochromator | θmax = 25.0°, θmin = 2.0° |
θ–2θ scans | h = −13→11 |
Absorption correction: analytical (de Meulenaer & Tompa, 1965) | k = 0→13 |
Tmin = 0.06, Tmax = 0.46 | l = 0→19 |
3423 measured reflections | 1 standard reflections every 30 min |
3423 independent reflections | intensity decay: <1% |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.038 | H-atom parameters not defined |
wR(F2) = 0.120 | Calculated w = 1/[σ2(Fo2) + (0.1P)2] where P = (Fo2 + 2Fc2)/3 |
S = 0.96 | (Δ/σ)max = 0.185 |
3423 reflections | Δρmax = 2.46 e Å−3 |
259 parameters | Δρmin = −2.35 e Å−3 |
0 restraints |
Na8(MnW6O24)·18H2O | V = 1953 (3) Å3 |
Mr = 2050.22 | Z = 2 |
Monoclinic, P21/c | Mo Kα radiation |
a = 11.686 (12) Å | µ = 18.09 mm−1 |
b = 11.671 (6) Å | T = 293 K |
c = 16.667 (18) Å | 0.20 × 0.18 × 0.03 mm |
β = 120.80 (4)° |
Enraf-Nonius CAD-4 diffractometer | 3017 reflections with I > 2σ(I) |
Absorption correction: analytical (de Meulenaer & Tompa, 1965) | Rint = 0.000 |
Tmin = 0.06, Tmax = 0.46 | 1 standard reflections every 30 min |
3423 measured reflections | intensity decay: <1% |
3423 independent reflections |
R[F2 > 2σ(F2)] = 0.038 | 0 restraints |
wR(F2) = 0.120 | H-atom parameters not defined |
S = 0.96 | (Δ/σ)max = 0.185 |
3423 reflections | Δρmax = 2.46 e Å−3 |
259 parameters | Δρmin = −2.35 e Å−3 |
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 on F2 for ALL reflections except for 0 with very negative F2 or flagged by the user for potential systematic errors. Weighted R-factors wR and all goodnesses of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The observed criterion of F2 > σ(F2) is used only for calculating _refine_ls_R_factor_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. |
x | y | z | Uiso*/Ueq | ||
Mn | 0 | 0 | 0 | 0.0164 (4) | |
W1 | −0.25336 (4) | 0.03819 (4) | −0.20259 (3) | 0.0201 (2) | |
W2 | −0.15371 (4) | 0.24033 (4) | −0.05491 (3) | 0.0201 (2) | |
W3 | 0.10143 (4) | 0.19989 (4) | 0.15551 (3) | 0.0207 (2) | |
O112 | −0.1763 (7) | 0.0588 (7) | −0.0554 (5) | 0.0198 (15) | |
O113 | 0.0507 (7) | 0.0222 (6) | 0.1273 (4) | 0.019 (2) | |
O123 | 0.0456 (7) | 0.1612 (6) | 0.0083 (5) | 0.0192 (15) | |
O12 | −0.1812 (8) | 0.1930 (7) | −0.1745 (5) | 0.026 (2) | |
O13 | 0.2665 (7) | 0.1243 (7) | 0.1877 (5) | 0.025 (2) | |
O23 | −0.0884 (7) | 0.2306 (7) | 0.0784 (5) | 0.022 (2) | |
O1A | −0.4176 (8) | 0.0702 (7) | −0.2307 (6) | 0.030 (2) | |
O1B | −0.2620 (9) | 0.0369 (8) | −0.3099 (6) | 0.033 (2) | |
O2A | −0.3172 (8) | 0.2688 (8) | −0.0855 (6) | 0.030 (2) | |
O2B | −0.0873 (7) | 0.3747 (7) | −0.0577 (5) | 0.026 (2) | |
O3A | 0.1557 (8) | 0.3357 (7) | 0.1476 (5) | 0.026 (2) | |
O3B | 0.1088 (9) | 0.1988 (8) | 0.2629 (6) | 0.034 (2) | |
Na1 | 0.1454 (5) | 0.4346 (4) | 0.0219 (3) | 0.0303 (10) | |
Na2 | 0.4452 (5) | 0.6093 (5) | 0.4181 (3) | 0.0390 (12) | |
Na3 | 0.1404 (13) | 0.5265 (11) | 0.2145 (6) | 0.129 (5) | |
Na4 | 0.393 (3) | 0.066 (2) | 0.4637 (16) | 0.37 (3) | |
OW1 | 0.1190 (9) | 0.4258 (10) | 0.3274 (7) | 0.046 (2) | |
OW2 | 0.3502 (8) | 0.4902 (8) | 0.4940 (6) | 0.034 (2) | |
OW3 | 0.2225 (11) | 0.6808 (10) | 0.3240 (8) | 0.052 (3) | |
OW4 | 0.3662 (9) | 0.4999 (9) | 0.1009 (7) | 0.051 (3) | |
OW5 | 0.3817 (10) | 0.4445 (10) | 0.3148 (8) | 0.052 (3) | |
OW6 | 0.2318 (11) | 0.2749 (10) | −0.0175 (9) | 0.058 (3) | |
OW7 | 0.5285 (12) | 0.7121 (10) | 0.3319 (9) | 0.059 (3) | |
OW8 | 0.0977 (11) | 0.5190 (12) | −0.1193 (7) | 0.064 (4) | |
OW9 | 0.5220 (12) | 0.7410 (10) | 0.5482 (8) | 0.057 (3) |
U11 | U22 | U33 | U12 | U13 | U23 | |
Mn | 0.0157 (10) | 0.0160 (11) | 0.0189 (10) | 0.0007 (9) | 0.0100 (8) | 0.0030 (8) |
W1 | 0.0188 (3) | 0.0218 (3) | 0.0184 (2) | 0.0008 (2) | 0.0085 (2) | 0.00144 (15) |
W2 | 0.0207 (3) | 0.0142 (3) | 0.0271 (3) | 0.0004 (2) | 0.0135 (2) | 0.0011 (2) |
W3 | 0.0255 (3) | 0.0173 (3) | 0.0210 (2) | −0.0019 (2) | 0.0131 (2) | −0.00330 (15) |
O112 | 0.018 (4) | 0.020 (4) | 0.022 (4) | 0.004 (3) | 0.011 (3) | 0.002 (3) |
O113 | 0.021 (4) | 0.021 (4) | 0.013 (3) | −0.003 (3) | 0.007 (3) | −0.005 (3) |
O123 | 0.018 (4) | 0.014 (4) | 0.026 (3) | 0.000 (3) | 0.011 (3) | 0.003 (3) |
O12 | 0.033 (4) | 0.022 (4) | 0.024 (4) | −0.005 (3) | 0.016 (3) | 0.003 (3) |
O13 | 0.016 (3) | 0.018 (4) | 0.037 (4) | −0.001 (3) | 0.011 (3) | −0.003 (3) |
O23 | 0.022 (4) | 0.025 (4) | 0.024 (4) | 0.001 (3) | 0.014 (3) | −0.002 (3) |
O1A | 0.018 (4) | 0.027 (5) | 0.039 (4) | −0.003 (3) | 0.010 (3) | 0.000 (4) |
O1B | 0.040 (5) | 0.037 (5) | 0.029 (4) | 0.004 (4) | 0.022 (4) | 0.004 (3) |
O2A | 0.016 (4) | 0.033 (5) | 0.041 (4) | 0.004 (3) | 0.014 (3) | −0.001 (4) |
O2B | 0.020 (4) | 0.021 (4) | 0.037 (4) | −0.004 (3) | 0.013 (3) | 0.001 (3) |
O3A | 0.030 (4) | 0.020 (4) | 0.031 (4) | 0.001 (3) | 0.018 (3) | 0.005 (3) |
O3B | 0.048 (6) | 0.031 (5) | 0.028 (4) | 0.005 (4) | 0.023 (4) | −0.001 (3) |
Na1 | 0.035 (3) | 0.025 (2) | 0.032 (2) | 0.001 (2) | 0.018 (2) | 0.002 (2) |
Na2 | 0.037 (3) | 0.041 (3) | 0.041 (3) | 0.004 (2) | 0.022 (2) | 0.008 (2) |
Na3 | 0.170 (11) | 0.151 (10) | 0.048 (4) | −0.093 (9) | 0.044 (6) | −0.017 (5) |
Na4 | 0.58 (5) | 0.45 (4) | 0.31 (3) | −0.43 (4) | 0.39 (4) | −0.31 (3) |
OW1 | 0.037 (5) | 0.062 (7) | 0.044 (5) | 0.004 (5) | 0.023 (4) | −0.017 (5) |
OW2 | 0.025 (4) | 0.036 (5) | 0.042 (5) | 0.001 (4) | 0.017 (4) | 0.001 (4) |
OW3 | 0.055 (6) | 0.047 (7) | 0.074 (7) | 0.017 (5) | 0.047 (6) | 0.033 (5) |
OW4 | 0.028 (5) | 0.036 (6) | 0.067 (6) | −0.007 (4) | 0.009 (5) | 0.003 (5) |
OW5 | 0.034 (5) | 0.070 (8) | 0.058 (6) | −0.006 (5) | 0.028 (5) | −0.027 (6) |
OW6 | 0.059 (7) | 0.041 (6) | 0.103 (9) | −0.020 (5) | 0.063 (7) | −0.031 (6) |
OW7 | 0.065 (7) | 0.052 (7) | 0.087 (8) | 0.023 (6) | 0.059 (7) | 0.022 (6) |
OW8 | 0.048 (6) | 0.109 (11) | 0.049 (6) | 0.031 (7) | 0.034 (5) | 0.023 (6) |
OW9 | 0.059 (7) | 0.049 (7) | 0.073 (7) | 0.007 (5) | 0.041 (6) | 0.003 (5) |
Mn—O112i | 1.903 (7) | O2B—Na1ii | 2.488 (9) |
Mn—O112 | 1.903 (7) | O2B—Na3ii | 2.624 (12) |
Mn—O113i | 1.905 (7) | O3A—Na1 | 2.339 (9) |
Mn—O113 | 1.905 (7) | O3A—Na3 | 2.54 (2) |
Mn—O123i | 1.941 (7) | Na1—OW8 | 2.341 (11) |
Mn—O123 | 1.941 (7) | Na1—OW4 | 2.344 (10) |
Mn—W1 | 3.182 (3) | Na1—OW6 | 2.367 (12) |
Mn—W1i | 3.182 (3) | Na1—O2Bii | 2.488 (9) |
Mn—W2 | 3.201 (2) | Na1—Na3 | 3.413 (12) |
Mn—W2i | 3.201 (2) | Na1—Na1ii | 3.446 (10) |
Mn—W3i | 3.228 (2) | Na1—Na4iii | 3.49 (2) |
Mn—W3 | 3.228 (2) | Na1—Na3ii | 3.662 (12) |
W1—O1B | 1.739 (8) | Na2—OW2iv | 2.372 (10) |
W1—O1A | 1.768 (8) | Na2—OW3 | 2.398 (12) |
W1—O13i | 1.929 (8) | Na2—OW9 | 2.424 (13) |
W1—O12 | 1.947 (8) | Na2—OW7 | 2.426 (12) |
W1—O112 | 2.150 (7) | Na2—OW5 | 2.430 (12) |
W1—O113i | 2.153 (7) | Na2—OW2 | 2.490 (10) |
W1—W2 | 3.169 (2) | Na2—Na2iv | 3.467 (10) |
W1—W3i | 3.172 (2) | Na2—Na3 | 3.572 (11) |
W2—O2A | 1.739 (8) | Na3—OW1 | 2.338 (14) |
W2—O2B | 1.761 (8) | Na3—OW3 | 2.39 (2) |
W2—O12 | 1.930 (8) | Na3—OW8ii | 2.45 (2) |
W2—O23 | 1.949 (7) | Na3—OW5 | 2.61 (2) |
W2—O112 | 2.134 (8) | Na3—O2Bii | 2.624 (12) |
W2—O123 | 2.208 (7) | Na3—Na1ii | 3.662 (12) |
W3—O3A | 1.737 (8) | Na4—OW9iv | 2.52 (2) |
W3—O3B | 1.747 (8) | Na4—O1Bi | 2.52 (2) |
W3—O13 | 1.931 (8) | Na4—OW4v | 2.57 (2) |
W3—O23 | 1.944 (8) | Na4—Na4vi | 2.65 (7) |
W3—O113 | 2.142 (7) | Na4—OW6v | 2.77 (3) |
W3—O123 | 2.239 (7) | Na4—Na1v | 3.49 (2) |
W3—W1i | 3.172 (2) | OW2—Na2iv | 2.372 (10) |
W3—Na1 | 3.728 (5) | OW4—Na4iii | 2.57 (2) |
O113—W1i | 2.153 (7) | OW6—Na4iii | 2.77 (3) |
O13—W1i | 1.929 (8) | OW8—Na3ii | 2.45 (2) |
O1B—Na4i | 2.52 (2) | OW9—Na4iv | 2.52 (2) |
O2B—Na1 | 2.439 (9) | ||
O112i—Mn—O112 | 180.0 | Mn—W3—Na1 | 99.07 (10) |
O112i—Mn—O113i | 97.7 (3) | Mn—O112—W2 | 104.8 (3) |
O112—Mn—O113i | 82.3 (3) | Mn—O112—W1 | 103.3 (3) |
O112i—Mn—O113 | 82.3 (3) | W2—O112—W1 | 95.4 (3) |
O112—Mn—O113 | 97.7 (3) | Mn—O113—W3 | 105.7 (3) |
O113i—Mn—O113 | 180.0 | Mn—O113—W1i | 103.1 (3) |
O112i—Mn—O123i | 82.8 (3) | W3—O113—W1i | 95.2 (3) |
O112—Mn—O123i | 97.2 (3) | Mn—O123—W2 | 100.8 (3) |
O113i—Mn—O123i | 82.6 (3) | Mn—O123—W3 | 100.9 (3) |
O113—Mn—O123i | 97.4 (3) | W2—O123—W3 | 94.7 (3) |
O112i—Mn—O123 | 97.2 (3) | W2—O12—W1 | 109.7 (4) |
O112—Mn—O123 | 82.8 (3) | W1i—O13—W3 | 110.6 (4) |
O113i—Mn—O123 | 97.4 (3) | W3—O23—W2 | 114.4 (4) |
O113—Mn—O123 | 82.6 (3) | W1—O1B—Na4i | 137.5 (6) |
O123i—Mn—O123 | 180.0 | W2—O2B—Na1 | 128.7 (4) |
O112i—Mn—W1 | 138.9 (2) | W2—O2B—Na1ii | 127.7 (4) |
O112—Mn—W1 | 41.1 (2) | Na1—O2B—Na1ii | 88.8 (3) |
O113i—Mn—W1 | 41.2 (2) | W2—O2B—Na3ii | 122.4 (4) |
O113—Mn—W1 | 138.8 (2) | Na1—O2B—Na3ii | 92.6 (4) |
O123i—Mn—W1 | 89.3 (2) | Na1ii—O2B—Na3ii | 83.7 (4) |
O123—Mn—W1 | 90.7 (2) | W3—O3A—Na1 | 131.7 (4) |
O112i—Mn—W1i | 41.1 (2) | W3—O3A—Na3 | 131.0 (4) |
O112—Mn—W1i | 138.9 (2) | Na1—O3A—Na3 | 88.7 (4) |
O113i—Mn—W1i | 138.8 (2) | O3A—Na1—OW8 | 169.9 (4) |
O113—Mn—W1i | 41.2 (2) | O3A—Na1—OW4 | 96.9 (4) |
O123i—Mn—W1i | 90.7 (2) | OW8—Na1—OW4 | 93.1 (4) |
O123—Mn—W1i | 89.3 (2) | O3A—Na1—OW6 | 91.5 (4) |
W1—Mn—W1i | 180.0 | OW8—Na1—OW6 | 88.1 (5) |
O112i—Mn—W2 | 139.9 (2) | OW4—Na1—OW6 | 84.8 (4) |
O112—Mn—W2 | 40.1 (2) | O3A—Na1—O2B | 83.0 (3) |
O113i—Mn—W2 | 89.5 (2) | OW8—Na1—O2B | 87.0 (4) |
O113—Mn—W2 | 90.5 (2) | OW4—Na1—O2B | 177.3 (4) |
O123i—Mn—W2 | 137.3 (2) | OW6—Na1—O2B | 97.9 (4) |
O123—Mn—W2 | 42.7 (2) | O3A—Na1—O2Bii | 97.0 (3) |
W1—Mn—W2 | 59.54 (3) | OW8—Na1—O2Bii | 84.9 (4) |
W1i—Mn—W2 | 120.46 (3) | OW4—Na1—O2Bii | 86.1 (4) |
O112i—Mn—W2i | 40.1 (2) | OW6—Na1—O2Bii | 168.2 (4) |
O112—Mn—W2i | 139.9 (2) | O2B—Na1—O2Bii | 91.2 (3) |
O113i—Mn—W2i | 90.5 (2) | O3A—Na1—Na3 | 48.0 (3) |
O113—Mn—W2i | 89.5 (2) | OW8—Na1—Na3 | 134.7 (4) |
O123i—Mn—W2i | 42.7 (2) | OW4—Na1—Na3 | 85.0 (4) |
O123—Mn—W2i | 137.3 (2) | OW6—Na1—Na3 | 136.4 (5) |
W1—Mn—W2i | 120.46 (3) | O2B—Na1—Na3 | 92.9 (3) |
W1i—Mn—W2i | 59.54 (3) | O2Bii—Na1—Na3 | 49.8 (3) |
W2—Mn—W2i | 180.0 | O3A—Na1—Na1ii | 90.1 (3) |
O112i—Mn—W3i | 89.5 (2) | OW8—Na1—Na1ii | 84.2 (3) |
O112—Mn—W3i | 90.5 (2) | OW4—Na1—Na1ii | 131.1 (4) |
O113i—Mn—W3i | 39.7 (2) | OW6—Na1—Na1ii | 143.5 (4) |
O113—Mn—W3i | 140.3 (2) | O2B—Na1—Na1ii | 46.2 (2) |
O123i—Mn—W3i | 42.9 (2) | O2Bii—Na1—Na1ii | 45.0 (2) |
O123—Mn—W3i | 137.1 (2) | Na3—Na1—Na1ii | 64.5 (3) |
W1—Mn—W3i | 59.31 (5) | O3A—Na1—Na4iii | 125.3 (4) |
W1i—Mn—W3i | 120.69 (5) | OW8—Na1—Na4iii | 61.6 (4) |
W2—Mn—W3i | 118.82 (5) | OW4—Na1—Na4iii | 47.6 (6) |
W2i—Mn—W3i | 61.18 (5) | OW6—Na1—Na4iii | 52.4 (5) |
O112i—Mn—W3 | 90.5 (2) | O2B—Na1—Na4iii | 134.4 (6) |
O112—Mn—W3 | 89.5 (2) | O2Bii—Na1—Na4iii | 115.8 (5) |
O113i—Mn—W3 | 140.3 (2) | Na3—Na1—Na4iii | 132.7 (6) |
O113—Mn—W3 | 39.7 (2) | Na1ii—Na1—Na4iii | 144.0 (3) |
O123i—Mn—W3 | 137.1 (2) | O3A—Na1—Na3ii | 128.7 (3) |
O123—Mn—W3 | 42.9 (2) | OW8—Na1—Na3ii | 41.4 (4) |
W1—Mn—W3 | 120.69 (5) | OW4—Na1—Na3ii | 134.4 (3) |
W1i—Mn—W3 | 59.31 (5) | OW6—Na1—Na3ii | 94.7 (4) |
W2—Mn—W3 | 61.18 (5) | O2B—Na1—Na3ii | 45.7 (3) |
W2i—Mn—W3 | 118.82 (5) | O2Bii—Na1—Na3ii | 86.3 (3) |
W3i—Mn—W3 | 180.0 | Na3—Na1—Na3ii | 121.8 (2) |
O1B—W1—O1A | 104.3 (4) | Na1ii—Na1—Na3ii | 57.3 (3) |
O1B—W1—O13i | 99.0 (4) | Na4iii—Na1—Na3ii | 97.5 (4) |
O1A—W1—O13i | 95.4 (4) | O3A—Na1—W3 | 20.4 (2) |
O1B—W1—O12 | 92.6 (4) | OW8—Na1—W3 | 151.1 (4) |
O1A—W1—O12 | 98.4 (4) | OW4—Na1—W3 | 110.6 (3) |
O13i—W1—O12 | 159.2 (3) | OW6—Na1—W3 | 78.2 (3) |
O1B—W1—O112 | 160.7 (4) | O2B—Na1—W3 | 70.0 (2) |
O1A—W1—O112 | 92.4 (3) | O2Bii—Na1—W3 | 112.1 (2) |
O13i—W1—O112 | 88.7 (3) | Na3—Na1—W3 | 66.1 (2) |
O12—W1—O112 | 75.2 (3) | Na1ii—Na1—W3 | 91.7 (2) |
O1B—W1—O113i | 93.7 (3) | Na4iii—Na1—W3 | 123.6 (3) |
O1A—W1—O113i | 160.9 (3) | Na3ii—Na1—W3 | 113.9 (2) |
O13i—W1—O113i | 74.9 (3) | OW2iv—Na2—OW3 | 171.0 (4) |
O12—W1—O113i | 87.2 (3) | OW2iv—Na2—OW9 | 87.9 (4) |
O112—W1—O113i | 71.2 (3) | OW3—Na2—OW9 | 98.3 (5) |
O1B—W1—W2 | 127.6 (3) | OW2iv—Na2—OW7 | 91.4 (4) |
O1A—W1—W2 | 88.0 (3) | OW3—Na2—OW7 | 94.1 (4) |
O13i—W1—W2 | 130.8 (2) | OW9—Na2—OW7 | 98.0 (5) |
O12—W1—W2 | 35.0 (2) | OW2iv—Na2—OW5 | 84.0 (4) |
O112—W1—W2 | 42.1 (2) | OW3—Na2—OW5 | 88.7 (4) |
O113i—W1—W2 | 86.2 (2) | OW9—Na2—OW5 | 167.0 (5) |
O1B—W1—W3i | 88.7 (3) | OW7—Na2—OW5 | 92.4 (5) |
O1A—W1—W3i | 130.2 (3) | OW2iv—Na2—OW2 | 89.1 (3) |
O13i—W1—W3i | 34.7 (2) | OW3—Na2—OW2 | 84.8 (3) |
O12—W1—W3i | 129.4 (3) | OW9—Na2—OW2 | 87.5 (4) |
O112—W1—W3i | 87.8 (2) | OW7—Na2—OW2 | 174.5 (4) |
O113i—W1—W3i | 42.3 (2) | OW5—Na2—OW2 | 82.2 (4) |
W2—W1—W3i | 121.56 (5) | OW2iv—Na2—Na2iv | 45.9 (2) |
O1B—W1—Mn | 128.5 (3) | OW3—Na2—Na2iv | 127.6 (3) |
O1A—W1—Mn | 127.2 (3) | OW9—Na2—Na2iv | 86.8 (3) |
O13i—W1—Mn | 79.5 (2) | OW7—Na2—Na2iv | 137.0 (4) |
O12—W1—Mn | 79.7 (2) | OW5—Na2—Na2iv | 80.3 (4) |
O112—W1—Mn | 35.6 (2) | OW2—Na2—Na2iv | 43.2 (2) |
O113i—W1—Mn | 35.7 (2) | OW2iv—Na2—Na3 | 130.8 (4) |
W2—W1—Mn | 60.53 (5) | OW3—Na2—Na3 | 41.6 (4) |
W3i—W1—Mn | 61.06 (3) | OW9—Na2—Na3 | 138.9 (4) |
O2A—W2—O2B | 104.8 (4) | OW7—Na2—Na3 | 94.5 (4) |
O2A—W2—O12 | 100.1 (4) | OW5—Na2—Na3 | 47.0 (4) |
O2B—W2—O12 | 94.0 (3) | OW2—Na2—Na3 | 81.0 (3) |
O2A—W2—O23 | 94.3 (4) | Na2iv—Na2—Na3 | 109.6 (3) |
O2B—W2—O23 | 99.3 (3) | OW1—Na3—OW3 | 86.0 (4) |
O12—W2—O23 | 157.2 (3) | OW1—Na3—OW8ii | 81.8 (5) |
O2A—W2—O112 | 94.2 (3) | OW3—Na3—OW8ii | 122.4 (8) |
O2B—W2—O112 | 159.9 (3) | OW1—Na3—O3A | 88.5 (5) |
O12—W2—O112 | 75.9 (3) | OW3—Na3—O3A | 155.1 (7) |
O23—W2—O112 | 85.5 (3) | OW8ii—Na3—O3A | 80.7 (5) |
O2A—W2—O123 | 162.2 (4) | OW1—Na3—OW5 | 80.0 (5) |
O2B—W2—O123 | 90.8 (3) | OW3—Na3—OW5 | 84.7 (5) |
O12—W2—O123 | 87.1 (3) | OW8ii—Na3—OW5 | 146.0 (7) |
O23—W2—O123 | 74.3 (3) | O3A—Na3—OW5 | 70.4 (5) |
O112—W2—O123 | 71.6 (3) | OW1—Na3—O2Bii | 162.6 (6) |
O2A—W2—W1 | 90.1 (3) | OW3—Na3—O2Bii | 103.1 (5) |
O2B—W2—W1 | 129.3 (3) | OW8ii—Na3—O2Bii | 80.8 (4) |
O12—W2—W1 | 35.3 (2) | O3A—Na3—O2Bii | 89.0 (4) |
O23—W2—W1 | 128.0 (2) | OW5—Na3—O2Bii | 115.2 (5) |
O112—W2—W1 | 42.5 (2) | OW1—Na3—Na1 | 131.2 (5) |
O123—W2—W1 | 86.4 (2) | OW3—Na3—Na1 | 139.7 (4) |
O2A—W2—Mn | 128.5 (3) | OW8ii—Na3—Na1 | 83.3 (3) |
O2B—W2—Mn | 126.7 (3) | O3A—Na3—Na1 | 43.3 (3) |
O12—W2—Mn | 79.4 (2) | OW5—Na3—Na1 | 87.4 (5) |
O23—W2—Mn | 77.8 (2) | O2Bii—Na3—Na1 | 46.4 (3) |
O112—W2—Mn | 35.1 (2) | OW1—Na3—Na2 | 80.6 (3) |
O123—W2—Mn | 36.6 (2) | OW3—Na3—Na2 | 41.8 (3) |
W1—W2—Mn | 59.94 (5) | OW8ii—Na3—Na2 | 157.2 (5) |
O3A—W3—O3B | 104.9 (4) | O3A—Na3—Na2 | 113.2 (5) |
O3A—W3—O13 | 94.9 (4) | OW5—Na3—Na2 | 42.9 (3) |
O3B—W3—O13 | 101.2 (4) | O2Bii—Na3—Na2 | 116.1 (4) |
O3A—W3—O23 | 96.9 (4) | Na1—Na3—Na2 | 119.3 (4) |
O3B—W3—O23 | 96.8 (4) | OW1—Na3—Na1ii | 120.9 (5) |
O13—W3—O23 | 155.1 (3) | OW3—Na3—Na1ii | 121.1 (6) |
O3A—W3—O113 | 159.6 (3) | OW8ii—Na3—Na1ii | 39.1 (3) |
O3B—W3—O113 | 94.7 (4) | O3A—Na3—Na1ii | 82.3 (3) |
O13—W3—O113 | 75.1 (3) | OW5—Na3—Na1ii | 145.5 (5) |
O23—W3—O113 | 86.5 (3) | O2Bii—Na3—Na1ii | 41.7 (2) |
O3A—W3—O123 | 90.8 (3) | Na1—Na3—Na1ii | 58.2 (2) |
O3B—W3—O123 | 162.8 (4) | Na2—Na3—Na1ii | 154.8 (3) |
O13—W3—O123 | 84.3 (3) | OW9iv—Na4—O1Bi | 113.9 (10) |
O23—W3—O123 | 73.7 (3) | OW9iv—Na4—OW4v | 124.7 (7) |
O113—W3—O123 | 70.8 (3) | O1Bi—Na4—OW4v | 118.5 (7) |
O3A—W3—W1i | 129.6 (3) | OW9iv—Na4—Na4vi | 103.5 (10) |
O3B—W3—W1i | 90.7 (3) | O1Bi—Na4—Na4vi | 97.4 (9) |
O13—W3—W1i | 34.7 (2) | OW4v—Na4—Na4vi | 86.5 (13) |
O23—W3—W1i | 129.0 (2) | OW9iv—Na4—OW6v | 74.1 (8) |
O113—W3—W1i | 42.5 (2) | O1Bi—Na4—OW6v | 110.0 (12) |
O123—W3—W1i | 84.6 (2) | OW4v—Na4—OW6v | 72.8 (5) |
O3A—W3—Mn | 126.6 (2) | Na4vi—Na4—OW6v | 151.2 (11) |
O3B—W3—Mn | 128.5 (3) | OW9iv—Na4—Na1v | 116.2 (10) |
O13—W3—Mn | 78.3 (2) | O1Bi—Na4—Na1v | 97.3 (7) |
O23—W3—Mn | 77.1 (2) | OW4v—Na4—Na1v | 42.3 (3) |
O113—W3—Mn | 34.6 (2) | Na4vi—Na4—Na1v | 126.8 (12) |
O123—W3—Mn | 36.2 (2) | OW6v—Na4—Na1v | 42.6 (4) |
W1i—W3—Mn | 59.63 (5) | Na2iv—OW2—Na2 | 90.9 (3) |
O3A—W3—Na1 | 27.9 (3) | Na3—OW3—Na2 | 96.5 (5) |
O3B—W3—Na1 | 131.9 (3) | Na1—OW4—Na4iii | 90.1 (8) |
O13—W3—Na1 | 94.5 (3) | Na2—OW5—Na3 | 90.1 (4) |
O23—W3—Na1 | 86.0 (2) | Na1—OW6—Na4iii | 85.0 (5) |
O113—W3—Na1 | 133.4 (2) | Na1—OW8—Na3ii | 99.6 (5) |
O123—W3—Na1 | 63.0 (2) | Na2—OW9—Na4iv | 118.5 (6) |
W1i—W3—Na1 | 124.09 (9) |
Symmetry codes: (i) −x, −y, −z; (ii) −x, −y+1, −z; (iii) x, −y+1/2, z−1/2; (iv) −x+1, −y+1, −z+1; (v) x, −y+1/2, z+1/2; (vi) −x+1, −y, −z+1. |
Experimental details
Crystal data | |
Chemical formula | Na8(MnW6O24)·18H2O |
Mr | 2050.22 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 293 |
a, b, c (Å) | 11.686 (12), 11.671 (6), 16.667 (18) |
β (°) | 120.80 (4) |
V (Å3) | 1953 (3) |
Z | 2 |
Radiation type | Mo Kα |
µ (mm−1) | 18.09 |
Crystal size (mm) | 0.20 × 0.18 × 0.03 |
Data collection | |
Diffractometer | Enraf-Nonius CAD-4 diffractometer |
Absorption correction | Analytical (de Meulenaer & Tompa, 1965) |
Tmin, Tmax | 0.06, 0.46 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 3423, 3423, 3017 |
Rint | 0.000 |
(sin θ/λ)max (Å−1) | 0.594 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.038, 0.120, 0.96 |
No. of reflections | 3423 |
No. of parameters | 259 |
H-atom treatment | H-atom parameters not defined |
(Δ/σ)max | 0.185 |
Δρmax, Δρmin (e Å−3) | 2.46, −2.35 |
Computer programs: Please specify, local software, SHELXS86 (Sheldrick, 1990), SHELXL93 (Sheldrick, 1993), ORTEPII (Johnson, 1976).
Mn—O112 | 1.903 (7) | W2—O12 | 1.930 (8) |
Mn—O113 | 1.905 (7) | W2—O23 | 1.949 (7) |
Mn—O123 | 1.941 (7) | W2—O112 | 2.134 (8) |
W1—O1B | 1.739 (8) | W2—O123 | 2.208 (7) |
W1—O1A | 1.768 (8) | W3—O3A | 1.737 (8) |
W1—O13i | 1.929 (8) | W3—O3B | 1.747 (8) |
W1—O12 | 1.947 (8) | W3—O13 | 1.931 (8) |
W1—O112 | 2.150 (7) | W3—O23 | 1.944 (8) |
W1—O113i | 2.153 (7) | W3—O113 | 2.142 (7) |
W2—O2A | 1.739 (8) | W3—O123 | 2.239 (7) |
W2—O2B | 1.761 (8) |
Symmetry code: (i) −x, −y, −z. |
As part of our studies into the structures and range of heteroatoms found in heteropolyoxomolybdates and -tungstates, we have examined the structure of the title compound, Na8(MnW6O24).18H2O.
The structure consists of Na+ cations, an [MnW6O24]8− anion and water molecules of crystallization. The geometry of the anion is based on the standard Anderson structure (Anderson, 1937), with six WO6 octahedral edge-sharing units surrounding the central MnO6 octahedron and with all metal atoms essentially in a common plane (the maximum deviation of a W atom from the least-squares plane is 0.028 Å).
A view of the anion is shown in Fig. 1. The central MnIV is coordinated to six O atoms in a slightly distorted octahedral arrangement. There are three crystallographically unique Mn—O bonds [1.903 (7), 1.905 (7) and 1.941 (7) Å]. Two of the bonds are significantly shorter than the third by 2.2σ. These bond distances may be compared with that found in Na2K6[MnW6O24].12H2O [one independent distance of 1.943 (7) Å; Sergienko et al., 1979] and with those in K6[MnMo9O32]·6H2O [1.884 (6) Å; Dunne et al., 1992] and (NH4)6[MnMo9O32]·6H2O [1.897 (3) Å; Stratemeier et al., 1992].
The Mn—O distances in [MnMo9O32]6− are shorter than in [MnW6O24]8−, which is related to the extent of polymerization of the two types of polyoxometalate cage, while the differences in the two Anderson-based structures are associated with the immediate environments surrounding the O atoms of the central MnO6 unit. Thus, the bond valences (Brown & Altermatt, 1985) of O112, O113 and O123 are 1.76 (5), 1.74 (5) and 1.48 (5), respectively, compared with that of the oxygen (all central O atoms are equivalent) in Na2K6[MnW6O24].12H2O, which is 1.67 (5). All are somewhat less than the expected value of 2, and indicate close contacts to neighbouring atoms in each case. For Na8[MnW6O24].18H2O these are to water molecules, based on the short O···O distances (2.70–2.82 Å), while in Na2K6[MnW6O24].12H2O the interaction is to the (unique) K+ ion.
Although the distances to the H atoms of the adjacent water molecules are unknown, the H···O bond valence-O···O distance correlation plot provided by Brown & Altermatt (1985) may be used to calculate the contribution for these types of interactions to the bond valence sums for the central O atoms of the MnO6 unit in the present structure. The bond valences increase to 1.94 (5), 1.94 (5) and 1.67 (5) for O112, O113 and O123, respectively. For the central O atom in Na2K6[MnW6O24].12H2O, inclusion of the contribution from the K+···O interaction (2.782 Å) gives a bond valence of 1.84 (6). Of all such interactions in the two structures, the only really low value is to O123 in Na8[MnW6O24].18H2O, but this may simply result from the packing of the water molecules and Na+ ions around the anion, such that no further strong contacts can be made [the next shortest distance is O123···OW6 = 2.764 (13) Å]. Interestingly, O123 has the only interaction of all the centrally located O atoms with an Na+ ion [3.365 (9) Å], although any contribution to the bond valence sum from this ion is negligible. Thus, it appears that in Anderson-based structures that do not contain protonated centrally located O atoms, such as in (NH4)4[H6CoMo6O24]·4H2O (Nolan et al., 1996), strong interactions with adjacent water molecules can have a significant effect on the heteroatom-oxygen distances in the XO6 unit (X = heteroatom).
In the present structure, the O—Mn—O angles vary from 82.3 (3) to 97.7 (3)°, indicating the extent of angular distortion around the MnIV, and they are similar to the range of 82.6 (3) to 97.4 (3)° found in Na2K6[MnW6O24].12H2O. The W atoms are all six-coordinate, although the distortion away from octahedral symmetry is extensive. Each W atom is coordinated twice to three-coordinate O atoms, twice to two-coordinate O atoms and twice to terminal O atoms. The W—O bond lengths decrease with decreasing coordination of the O atom. The average Mn···W and W···W distances are 3.204 (19) and 3.171 (2) Å, respectively. All cation-anion distances are longer than 2.339 Å and anion-water distances longer than 2.70 Å. Although no H atoms were located, the short anion-water distances provide evidence for hydrogen bonding between the anion and water molecules.