Regioselective synthesis and characterization of monovanadium-substituted β-octa­molybdate [VMo7O26]5−

Krivosudský, L.; Roller, A.; Rompel, A.

doi:10.1107/S205322961900620X

research papers

STRUCTURAL
CHEMISTRY

ISSN: 2053-2296

Volume 75| Part 7| July 2019| Pages 872-876

https://doi.org/10.1107/S205322961900620X

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Regioselective synthesis and characterization of monovanadium-substituted β-octamolybdate [VMo₇O₂₆]⁵⁻

Lukáš Krivosudský,^a,^b Alexander Roller ^c and Annette Rompel ^a ^*

^aUniversität Wien, Fakultät für Chemie, Institut für Biophysikalische Chemie, Althanstrasse 14, Wien 1090, Austria, ^bComenius University in Bratislava, Faculty of Natural Sciences, Department of Inorganic Chemistry, Ilkovičova 6, 842 15 Bratislava, Slovakia, and ^cUniversität Wien, Fakultät für Chemie, Zentrum für Röntgenstrukturanalyse, Währinger Strasse 42, 1090 Wien, Austria
^*Correspondence e-mail: annette.rompel@univie.ac.at

Edited by A. R. Kennedy, University of Strathclyde, Scotland (Received 14 March 2019; accepted 2 May 2019; online 7 June 2019)

The monovanadium-substituted polyoxometalate anion [VMo₇O₂₆]⁵⁻, exhibiting a β-octamolybdate archetype structure, was selectively prepared as pentapotassium [hexaikosaoxido(heptamolybdenumvanadium)]ate hexahydrate, K₅[VMo₇O₂₆]·6H₂O (VMo₇), by oxidation of a reduced vanadomolybdate solution with hydrogen peroxide in a fast one-pot approach. X-ray structure analysis revealed that the V atom occupies a single position in the cluster that differs from the other positions by the presence of one doubly-bonded O atom instead of two terminal oxide ligands in all other positions. The composition and structure of VMo₇ was also confirmed by elemental analyses and IR spectroscopy. The selectivity of the synthesis was inspected by a ⁵¹V NMR investigation which showed that this species bound about 95% of V^V in the crystallization solution. Upon dissolution of VMo₇ in aqueous solution, the [VMo₇O₂₆]⁵⁻ anion is substantially decomposed, mostly into [VMo₅O₁₉]³⁻, α-[VMo₇O₂₆]⁴⁻ and [V₂Mo₄O₁₉]⁴⁻, depending on the pH.

Keywords: polyoxometalate; POM; octamolybdate; vanadium; ⁵¹V NMR spectroscopy; crystal structure.

CCDC reference: 1898165

1. Introduction

Polyoxometalates (POMs) of W, Mo and V represent an important group of inorganic metal–oxide clusters (Pope, 1983 ) whose structural variability gives rise to an exceptionally wide range of applications in catalysis (Wang & Yang, 2015 ), magnetism (Clemente-Juan et al., 2012 ), redox processes (Gumerova & Rompel, 2018 ) and materials chemistry (Song & Tsunashima, 2012 ), as well as in biological chemistry (Bijelic & Rompel, 2015 , 2017 ; Molitor et al., 2017 ; Fu et al., 2015 ; Bijelic et al., 2018 , 2019 ). Particularly interesting are photoactive POMs with applications in water splitting, the photooxidation of organic pollutants, photoreductive CO₂ activation and H₂ generation (Streb et al., 2019 ). Vanadium-containing POMs are a promising subgroup of photocatalysts. A V^V centre acts as a more efficient light absorber in comparison to Mo^VI/W^VI; moreover, it may easily promote a photoredox reaction via its photoreduction to a V^IV species. Substitution of some Mo or W atoms in molybdates and tungstates may therefore lead to enhanced photocatalytic properties (Streb, 2012 ). Substitution of one Mo atom in a Linqvist-type hexamolybdate, [Mo₆O₁₉]²⁻, by vanadium leads to enhanced photocatalytic degradation of a model organic dye under both aerobic and anaerobic conditions caused by a low-energy O→V LMCT (ligand-to-metal charge transfer) transition in [VMo₅O₁₉]³⁻ (Tucher et al., 2012 ). However, the controlled synthesis of mixed vanadomolybdates and vanadotungstates remains a serious challenge. Simple mixing of addenda-atom precursors leads to a complicated equilibria of several species (Pope, 1983; Howarth et al., 1991 ). The β-octamolybdate structure [Mo₈O₂₆]⁴⁻ (Fig. 1) is one of the main components in H⁺/OH⁻/MoO₄²⁻ systems under acidic conditions, yet only the disubstituted vanadium derivative [V₂Mo₆O₂₆]⁶⁻ is commonly known in the literature and has been structurally characterized (Nenner, 1985 ; Fei et al., 2015 ; Li et al., 2011 ). The two V atoms occupy chemically equivalent positions, denoted Mo_C. Very recently, a monovanadium-substituted derivative was prepared as H₄K₂Na₂(H₂O)₄(C₁₂H₁₂N₄O₂)[VMo₇O₂₆]·10H₂O (Zhao et al., 2018 ). In this case, the V atom was claimed to be statistically distributed in all positions of the parent β-octamolybdate anion.

Figure 1
Schematic representation of the structure of the β-octamolybdate anion [Mo₈O₂₆]⁴⁻. Chemically non-equivalent Mo atoms are shown in different colours: Mo_A green, Mo_B orange, Mo_C blue and O red.

In the current work, we present a regioselective synthesis of a new isomer of [VMo₇O₂₆]⁵⁻ in which the V atom occupies only Mo_C positions of the parent β-octamolybdate structure. The regioselectivity was achieved by controlled stepwise synthesis via vanadium peroxido complexes as precursors. The peroxide-mediated synthesis route (Schwendt et al., 2016 ) has already been successfully utilized for the synthesis of several polyoxometalates, such as [H_xV₁₀O₂₈]^(6–x)– (Jahr et al., 1963 ; Nakamura & Ozeki, 2001 ), [H_xPV₁₄O₄₂]^(9–x)–, Keggin structures [H_3+xPMo_12–xV_xO₄₀], and Wells–Dawson structures [H_6+xP₂Mo_18–xV_xO₆₂] (Odyakov et al., 2015 ) and [V₁₂O₃₀F₄(H₂O)₂]⁴⁻ (Krivosudský et al., 2014 ).

2. Experimental

All chemicals were purchased from Sigma–Aldrich (Austria) and used as received.

2.1. Synthesis and crystallization

For the preparation of K₅[VMo₇O₂₆]·6H₂O (VMo₇), K₂MoO₄ (1.67 g, 7 mmol) and VOSO₄·nH₂O (0.2 g, 1.22 mmol) were dissolved in distilled water (40 ml) by heating. HCl (0.7 ml of a 37% w/w solution) was added. When the temperature reached 80 °C, H₂O₂ (0.1 ml of a 30% w/w solution, 1 mmol) was added and the colour of the solution changed immediately from dark violet to orange. The solution was boiled for 1 min and the pH of the still hot solution was adjusted to 3.1 with 50% KOH solution. The clear-yellow solution was left to crystallize at 18 °C. Yellow block-shaped crystals were filtered off after 2 d, washed with water and ethanol and air-dried (yield 0.47 g, 33%, based on Mo). Elemental analysis (%) for K₅Mo₇VO₃₂H₁₂ (calculated): K 14.0 (13.6), Mo 46.6 (46.6), V 3.43 (3.53).

2.2. Elemental analysis

Elemental analyses were performed in aqueous solutions containing 2% HNO₃ using inductively coupled plasma mass spectrometry (PerkinElmer Elan 6000 ICP MS) for Mo and V, and atomic absorption spectroscopy (PerkinElmer 1100 Flame AAS) for K. Standards were prepared from single-element standard solutions of concentration 1000 mg l⁻¹ (Merck, Ultra Scientific and Analytika Prague).

2.3. IR spectroscopy

VMo₇ was identified by IR measurement on a Bruker Vertex70 IR Spectrometer equipped with a single reflection diamond-ATR (attenuated total reflectance) unit in the range 4000–100 cm⁻¹.

2.4. ⁵¹V NMR spectroscopy

⁵¹V nuclear magnetic resonance spectroscopy measurements of aqueous solutions (with 10% of D₂O used for locking, at 20 °C) were taken on a Bruker AV II+ 500 MHz instrument operating at 131.60 MHz for the ⁵¹V nucleus (2000 scans, accumulation time 0.05 s, relaxation delay 0.01 s). Chemical shift values are given with reference to VOCl₃ (0 ppm) as the standard.

2.5. Refinement

Crystal data, data collection, structure refinement and software details are summarized in Table 1. No H atoms were inserted on the free water O atoms due to the disorder and instability of the model. In the case of the disordered groups, one bond was added to the connectivity array (O15S—K3). The disordered Mo4A/V4 atoms occupying the same position of the POM anion were treated with half occupancies. The O atoms of the solvent molecules (O16S, O17S, O18S and O19S) and the partially occupied K3 and K4 atoms and their corresponding U_ij components are of low quality and were forced by the restrained ISOR to affect the standard deviation and approximate the U_ij components to isotropic behaviour.

Table 1
Experimental details

Crystal data
Chemical formula	K₅[VMo₇O₂₆]·6H₂O
M_r	1442.12
Crystal system, space group	Monoclinic, C2/c
Temperature (K)	143
a, b, c (Å)	12.9356 (10), 16.1978 (10), 13.8618 (9)
β (°)	90.962 (4)
V (Å³)	2904.0 (3)
Z	4
Radiation type	Mo Kα
μ (mm⁻¹)	4.06
Crystal size (mm)	0.1 × 0.1 × 0.1

Data collection
Diffractometer	Bruker D8 Venture
Absorption correction	Multi-scan (SADABS; Bruker, 2016 )
T_min, T_max	0.512, 0.564
No. of measured, independent and observed [I > 2σ(I)] reflections	80344, 4259, 4028
R_int	0.057
(sin θ/λ)_max (Å⁻¹)	0.705

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.027, 0.059, 1.26
No. of reflections	4259
No. of parameters	235
No. of restraints	37
H-atom treatment	H-atom parameters not defined
Δρ_max, Δρ_min (e Å⁻³)	0.64, −0.74
Computer programs: APEX3 (Bruker, 2018 ), SAINT (Bruker, 2016), SHELXS97 (Sheldrick, 2008 ), SHELXL2018 (Sheldrick, 2015 ), OLEX2 (Dolomanov et al., 2009 ), DIAMOND (Brandenburg, 2006 ), PLATON (Spek, 2009 ) and ShelXle (Hübschle, et al., 2011 ).

3. Results and discussion

Upon reaction of the initial H_xVO₄^(3–x)– and H_xMoO₄^(2–x)– precursors and adjustment of the pH to a certain value, complicated reaction mixtures with several equilibrated species are formed (Howarth et al., 1991). It was therefore necessary to choose a different synthesis approach that would favour the formation of [VMo₇O₂₆]⁵⁻. We employed a V^IV precursor (VOSO₄) that forms with molybdate mixed-valence polynuclear deep-blue vanadomolybdates at pH ≃1.5 (Müller et al., 2005 ; Botar et al., 2005 ). Subsequent addition of hydrogen peroxide resulted in an orange solution formed by immediate oxidation with vanadium peroxido complexes (Schwendt et al., 2016). The crucial point of the synthesis was the adjustment of the pH of the hot solution to 3.1. This value represents a region where the β-octamolybdate anion [Mo₈O₂₆]⁴⁻ is the main species present in the simple molybdate solutions at c_Mo = 0.1 mol dm⁻³ (Ozeki et al., 1988 ). We also obtained different products from solutions with the pH range 1.5–7.0; however, IR and ICP–MS analyses indicated that the products are mixtures and VMo₇ can only be obtained as a pure product in the pH range 2.8–3.5. Adjustment of the pH of the cooled solution leads to the formation of precipitates and an obvious reduction of vanadium (formation of a green solution).

The asymmetric unit of VMo₇ contains one half of the [VMo₇O₂₆]⁵⁻ POM anion lying on a centre of symmetry (Fig. 2). The K⁺ cations which compensate the charge of the anion occupy four positions, one of them at full occupancy (K2) and one disordered over two positions (K3 and K4). The K1 atom is coordinated by two [VMo₇O₂₆]⁵⁻ anions in an interesting fashion, forming an irregular twisted antiprismatic coordination polyhedron, with K—O distances in the range 2.703 (3)–2.767 (3) Å (Fig. 3) and without the participation of water molecules. The two square bases formed by oxido ligands O1, O2, O3 and O4 are twisted by approximately 10–13°. The [VMo₇O₂₆]⁵⁻ anion adopts the expected β-conformation (compare Figs. 1 and 2). The centrosymmetric anion was firstly refined as a pure [Mo₈O₂₆]⁴⁻ cluster for localization of the V atoms. While the Mo_A and Mo_B positions showed initial occupancies very close to 1 (≃0.96), significantly lower occupancies of the Mo atoms at the Mo_C positions indicated the presence of V atoms which are equally distributed in both symmetrically equivalent positions. The positioning of the V atoms at 0.5 occupancies in the Mo_C positions led to a significant improvement of the model. Moreover, it can be seen from Fig. 1 that the Mo_C atoms differ significantly from the Mo_A and Mo_B atoms in the replacement of one Mo=O bond by a bridging Mo—O bond. Therefore, we consider it reasonable that the V atom occupies preferably position Mo_C which is not only crystallographically, but also chemically, markedly non-equivalent to the other positions in the octametalate. In this context, we should note for the structure of H₄K₂Na₂(H₂O)₄(C₁₂H₁₂N₄O₂)[VMo₇O₂₆]·10H₂O (Zhao et al., 2018) that the displacement ellipsoids at the Mo_C positions are approximately twice as large as the ellipsoids of the Mo_A and Mo_B atoms, indicating that the V atom occupies preferably this position also in this structure, although the model was constrained with a statistical distribution of the V atoms throughout the anion. However, the selectivity of vanadium substitution is not known and the existence of such a species might be theoretically possible despite the fact that it was not predicted by speciation (Howarth et al., 1991). [VMo₇O₂₆]⁵⁻ consists of eight {Mo/VO₆} face- and edge-sharing octahedra. Except for atoms V4/Mo4A, all other Mo atoms are coordinated by two terminal oxido ligands, with shorter Mo=O double bonds in the range 1.601 (5)–1.726 (3) Å, and bridging oxide ligands exhibiting longer bond distances of up to 2.430 (2) Å for the Mo2—O13 bond incorporating the pentacoordinated O atom (see the supporting information for further details). All water molecules exhibit a certain degree of disorder and therefore we do not discuss the hydrogen-bond network. The water molecules complete an irregular coordination polyhedra around the potassium cations, forming a rich polymeric network based on electrostatic interactions (Fig. 4).

Figure 2
The molecular structure of [VMo₇O₂₆]⁵⁻ in VMo₇, showing the atom-labelling scheme. Displacement ellipsoids are shown at the 50% probability level. Colour code: Mo black, V blue and O red.

Figure 3
The coordination of the potassium cation K1 by two [VMo₇O₂₆]⁵⁻ ligands. Colour code: {Mo/VO₆} yellow octahedra and {KO₈} violet distorted square antiprism.

Figure 4
The crystal packing in VMo₇, viewed along the a axis. Colour code: {Mo/VO₆} yellow octahedra and {KO₈} violet distorted square antiprism. H atoms of water molecules have been omitted for clarity.

The IR spectrum of VMo₇ (Fig. 5) exhibits bands typical for a β-octamolybdate structure and the respective bands corresponding to Mo—O or V—O vibrations are not distinguishable. The stretching vibrations of the terminal Mo/V=O units appear at 934 and 888 cm⁻¹, whereas the peaks in the region from 470 to 840 cm⁻¹ correspond to the antisymmetric and symmetric deformation vibrations of the Mo—O—Mo and Mo—O—V bridging fragments. The crystallization water molecules exhibit typical bands for valence O—H vibrations and deformation H—O—H vibrations at 1610 and 3540 cm⁻¹, respectively.

Figure 5
The IR spectrum of VMo₇ in the region 4000–100 cm⁻¹.

We employed ⁵¹V NMR spectroscopy to inspect the synthesis and hydrolytic stability of VMo₇ (Fig. 6). All chemical shifts of the major species were assigned according to a very thorough speciation study based on NMR spectroscopy (⁵¹V, ⁹⁵Mo and ¹⁷O) and potentiometric data (Howarth et al., 1991). In the crystallization solution one day after the synthesis (Fig. 4a), the [VMo₇O₂₆]⁵⁻ anion (−534.2 ppm, 95% of V^V) is dominant, accompanied by a monovanadium-substituted hexamolybdate [VMo₅O₁₉]³⁻ (−505.0 ppm) and some minor species. After two days (Fig. 4b), when about 33% of the product has crystallized out, roughly 73% of V^V is still consumed in the [VMo₇O₂₆]⁵⁻ species. Thus, the NMR investigation confirms that a synthetic protocol starting from reduced mixed Mo/V polyoxometalates oxidized by H₂O₂ leads almost exclusively to the desired [VMo₇O₂₆]⁵⁻ anion. The speciation work by Howarth et al. proposed that [VMo₇O₂₆]⁵⁻ should be most stable around pH = 4.2. At this pH value (Fig. 4c), we observed substantial decomposition of VMo₇ into [VMo₅O₁₉]³⁻ (−505.1 ppm) and α-[VMo₇O₂₆]⁴⁻, a structure that resembles the Anderson–Evans archetype polyoxometalate capped by one Mo=O and one V=O unit (−502.9 ppm). Increased pH (Figs. 4d and 4e) results in a profound decomposition of [VMo₇O₂₆]⁵⁻ into hexametalate [V₂Mo₄O₁₉]⁴⁻ (−497.0 and −496.3 ppm). The results of the ⁵¹V NMR measurements showed that once the [VMo₇O₂₆]⁵⁻ anion is selectively formed from suitable precursors, it stays relatively intact in the solution for at least 24 h. On the other hand, by dissolution of VMo₇ in aqueous solution, hydrolysis takes place and the newly formed species, mostly [VMo₅O₁₉]³⁻, α-[VMo₇O₂₆]⁴⁻ and [V₂Mo₄O₁₉]⁴⁻, cannot give rise to the formation of [VMo₇O₂₆]⁵⁻ even under conditions when the equilibrium of the POM species should be favoured (0.5 M NaCl, pH = 4.2).

Figure 6
(a)/(b) The ⁵¹V NMR spectra of the crystallization solution of VMo₇ and (c)/(d)/(e) solutions obtained upon dissolution of crystallized VMo₇ at different pH values. Conditions: (a) 175 mM Mo^VI, 25 mM V^V, pH = 3.1, 24 h after the synthesis; (b) same conditions as (a) after another 24 h; (c)/(d)/(e) 10 mM V^V solution prepared from VMo₇ by dissolving it in 0.5 mM NaCl at pH values of (c) 4.0, (d) 5.2 and (e) 6.0. The pH was adjusted by the addition of a dilute KOH solution.

Supporting information

CCDC reference: 1898165

Crystal structure: contains datablock global. DOI: https://doi.org/10.1107/S205322961900620X/ky3170sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S205322961900620X/ky3170Isup2.hkl

Computing details top

Data collection: APEX3 (Bruker, 2018); cell refinement: SAINT (Bruker, 2016); data reduction: SAINT (Bruker, 2016); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2018 (Sheldrick, 2015); molecular graphics: OLEX2 (Dolomanov et al., 2009) and DIAMOND (Brandenburg, 2006); software used to prepare material for publication: PLATON (Spek, 2009) and ShelXle (Hübschle, et al., 2011) and OLEX2 (Dolomanov et al., 2009).

Pentapotassium [hexaikosaoxido(heptamolybdenumvanadium)]ate hexahydrate top

Crystal data top

K₅[VMo₇O₂₆]·6H₂O	F(000) = 2720
M_r = 1442.12	D_x = 3.298 Mg m⁻³
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
a = 12.9356 (10) Å	Cell parameters from 9243 reflections
b = 16.1978 (10) Å	θ = 3.5–30.0°
c = 13.8618 (9) Å	µ = 4.06 mm⁻¹
β = 90.962 (4)°	T = 143 K
V = 2904.0 (3) Å³	Block, clear yellow
Z = 4	0.1 × 0.1 × 0.1 mm

Data collection top

Bruker D8 Venture diffractometer	4028 reflections with I > 2σ(I)
Radiation source: sealed xray tube, Incoatec IuS	R_int = 0.057
φ and ω scans	θ_max = 30.1°, θ_min = 2.9°
Absorption correction: multi-scan (SADABS; Bruker, 2016)	h = −18→18
T_min = 0.512, T_max = 0.564	k = −22→22
80344 measured reflections	l = −19→19
4259 independent reflections

Refinement top

Refinement on F²	37 restraints
Least-squares matrix: full	Primary atom site location: heavy-atom method
R[F² > 2σ(F²)] = 0.027	H-atom parameters not defined
wR(F²) = 0.059	w = 1/[σ²(F_o²) + (0.0001P)² + 32.0908P] where P = (F_o² + 2F_c²)/3
S = 1.26	(Δ/σ)_max = 0.002
4259 reflections	Δρ_max = 0.64 e Å⁻³
235 parameters	Δρ_min = −0.73 e Å⁻³

Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.

Refinement. _olex2_refinement_description 1. Restrained distances K3-O17S ~ K4-O16S with sigma of 0.04 2. Uiso/Uaniso restraints and constraints Uanis(O16S) ~ Ueq, Uanis(O17S) ~ Ueq: with sigma of 0.02 and sigma for terminal atoms of 0.04 Uanis(K4) ~ Ueq, Uanis(K3) ~ Ueq: with sigma of 0.05 and sigma for terminal atoms of 0.1 Uanis(O19S) ~ Ueq, Uanis(O18S) ~ Ueq: with sigma of 0.02 and sigma for terminal atoms of 0.04 Uanis(Mo4A) = Uanis(V4) 3. Others Fixed Sof: V4(0.5) K3(0.6) O17S(0.3) Mo4A(0.5) K4(0.4) O16S(0.2) O19S(0.3) O18S(0.2)

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

	x	y	z	U_iso*/U_eq	Occ. (<1)
Mo1	0.60579 (2)	0.38037 (2)	0.98066 (2)	0.01081 (6)
Mo2	0.47932 (2)	0.21300 (2)	1.03581 (2)	0.01181 (6)
Mo3	0.65441 (2)	0.10564 (2)	0.92676 (2)	0.01002 (6)
K1	0.500000	0.25427 (7)	0.750000	0.01348 (19)
K2	0.31406 (6)	0.37807 (5)	0.90717 (7)	0.02218 (17)
O1	0.54136 (19)	0.38311 (16)	0.87068 (19)	0.0154 (5)
O2	0.41768 (19)	0.22432 (16)	0.92545 (19)	0.0162 (5)
O3	0.59213 (19)	0.11548 (16)	0.81722 (18)	0.0151 (5)
O4	0.7111 (2)	0.27748 (16)	0.7712 (2)	0.0172 (5)
O5	0.60418 (19)	0.47897 (16)	1.0214 (2)	0.0172 (5)
O6	0.3830 (2)	0.19028 (17)	1.1137 (2)	0.0181 (5)
O7	0.68024 (19)	0.00256 (16)	0.9364 (2)	0.0157 (5)
O8	0.90217 (19)	0.28854 (16)	0.84839 (18)	0.0134 (5)
O9	0.74853 (18)	0.37746 (15)	0.93218 (17)	0.0116 (4)
O10	0.50256 (18)	0.32975 (15)	1.05790 (18)	0.0132 (5)
O11	0.54021 (18)	0.10735 (15)	1.01354 (18)	0.0129 (5)
O12	0.78897 (18)	0.15146 (15)	0.89034 (18)	0.0121 (4)
O13	0.64659 (18)	0.24183 (15)	0.96599 (18)	0.0129 (5)
O14S	0.3275 (3)	0.4852 (2)	0.7528 (3)	0.0392 (8)
O15S	0.7757 (3)	−0.1362 (2)	1.1084 (3)	0.0349 (8)
V4	0.7746 (9)	0.2690 (7)	0.8831 (6)	0.0071 (3)	0.5
K3	0.6350 (7)	−0.0145 (4)	1.1512 (5)	0.0478 (15)	0.6
O17S	0.4632 (12)	0.0633 (9)	1.2324 (15)	0.020 (3)	0.3
Mo4A	0.7748 (4)	0.2706 (4)	0.8710 (2)	0.0071 (3)	0.5
K4	0.6247 (10)	−0.0282 (6)	1.1377 (7)	0.0296 (16)	0.4
O16S	0.500000	0.0715 (14)	1.250000	0.029 (6)	0.4
O19S	0.533 (2)	0.3893 (13)	1.262 (2)	0.033 (6)	0.3
O18S	0.500000	0.3867 (16)	1.250000	0.025 (7)	0.4

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Mo1	0.00751 (12)	0.01082 (13)	0.01402 (13)	0.00096 (9)	−0.00248 (10)	−0.00156 (10)
Mo2	0.00759 (12)	0.01365 (13)	0.01420 (13)	−0.00028 (10)	0.00014 (10)	−0.00243 (10)
Mo3	0.00816 (12)	0.01032 (13)	0.01151 (13)	0.00031 (9)	−0.00168 (9)	−0.00177 (10)
K1	0.0131 (4)	0.0150 (5)	0.0122 (4)	0.000	−0.0029 (3)	0.000
K2	0.0140 (3)	0.0156 (4)	0.0369 (5)	0.0019 (3)	−0.0020 (3)	−0.0053 (3)
O1	0.0117 (11)	0.0172 (12)	0.0170 (12)	0.0011 (9)	−0.0047 (9)	−0.0013 (10)
O2	0.0116 (11)	0.0172 (12)	0.0196 (13)	0.0007 (9)	−0.0029 (9)	−0.0024 (10)
O3	0.0133 (11)	0.0164 (12)	0.0154 (12)	−0.0002 (9)	−0.0037 (9)	−0.0028 (10)
O4	0.0132 (11)	0.0174 (12)	0.0210 (13)	−0.0010 (9)	−0.0002 (10)	0.0028 (10)
O5	0.0117 (11)	0.0155 (12)	0.0242 (13)	0.0012 (9)	−0.0044 (10)	−0.0042 (10)
O6	0.0124 (11)	0.0197 (13)	0.0222 (13)	−0.0030 (10)	0.0034 (10)	−0.0039 (10)
O7	0.0115 (11)	0.0133 (12)	0.0222 (13)	0.0004 (9)	−0.0015 (10)	−0.0013 (10)
O8	0.0117 (11)	0.0160 (12)	0.0124 (11)	−0.0007 (9)	−0.0010 (9)	0.0001 (9)
O9	0.0093 (10)	0.0113 (11)	0.0140 (11)	0.0000 (8)	−0.0019 (9)	0.0013 (9)
O10	0.0101 (11)	0.0132 (11)	0.0163 (12)	0.0011 (9)	0.0010 (9)	−0.0050 (9)
O11	0.0104 (11)	0.0135 (11)	0.0149 (11)	−0.0008 (9)	0.0013 (9)	−0.0001 (9)
O12	0.0097 (10)	0.0122 (11)	0.0143 (11)	0.0000 (8)	−0.0016 (9)	−0.0006 (9)
O13	0.0098 (11)	0.0120 (11)	0.0167 (12)	0.0002 (9)	−0.0011 (9)	−0.0001 (9)
O14S	0.052 (2)	0.039 (2)	0.0263 (17)	0.0065 (17)	−0.0009 (16)	−0.0059 (15)
O15S	0.0313 (17)	0.0275 (17)	0.046 (2)	−0.0023 (14)	−0.0003 (15)	0.0006 (15)
V4	0.00768 (16)	0.0105 (3)	0.0031 (9)	−0.00021 (16)	−0.0007 (7)	0.0010 (7)
K3	0.0307 (14)	0.063 (4)	0.050 (3)	0.015 (2)	0.014 (2)	0.038 (2)
O17S	0.031 (9)	0.010 (5)	0.019 (6)	−0.003 (6)	0.001 (6)	−0.002 (4)
Mo4A	0.00768 (16)	0.0105 (3)	0.0031 (9)	−0.00021 (16)	−0.0007 (7)	0.0010 (7)
K4	0.047 (4)	0.0252 (17)	0.0172 (15)	0.0130 (19)	0.0138 (18)	0.0008 (12)
O16S	0.037 (13)	0.021 (8)	0.029 (13)	0.000	0.018 (11)	0.000
O19S	0.049 (17)	0.041 (8)	0.008 (8)	−0.027 (9)	0.001 (10)	−0.008 (5)
O18S	0.036 (19)	0.017 (8)	0.021 (13)	0.000	−0.014 (12)	0.000

Geometric parameters (Å, º) top

Mo1—K1	4.0151 (6)	K2—O1	2.993 (3)
Mo1—K2	3.8924 (9)	K2—O2	2.838 (3)
Mo1—O1	1.726 (3)	K2—O4ⁱⁱⁱ	2.975 (3)
Mo1—O5	1.694 (3)	K2—O5^iv	2.725 (3)
Mo1—O9	1.976 (2)	K2—O6^v	2.790 (3)
Mo1—O10	1.910 (3)	K2—O7^vi	2.693 (3)
Mo1—O12ⁱ	2.288 (2)	K2—O10	3.279 (3)
Mo1—O13	2.315 (2)	K2—O14S	2.763 (4)
Mo1—V4	3.155 (12)	K2—O15S^vi	2.850 (4)
Mo1—Mo4A	3.219 (5)	O2—K4ⁱⁱ	3.339 (9)
Mo2—K1	4.0312 (4)	O3—K3ⁱⁱ	3.398 (9)
Mo2—K2	3.8433 (9)	O3—K3^vii	2.884 (9)
Mo2—O2	1.723 (3)	O3—K4ⁱⁱ	3.212 (13)
Mo2—O6	1.702 (3)	O3—K4^vii	2.899 (12)
Mo2—O8ⁱ	2.201 (2)	O4—V4	1.748 (9)
Mo2—O10	1.938 (2)	O4—Mo4A	1.601 (5)
Mo2—O11	1.911 (3)	O7—K3	3.056 (8)
Mo2—O13	2.430 (2)	O7—K4	2.935 (11)
Mo2—K4ⁱⁱ	4.056 (8)	O8—V4	1.755 (12)
Mo3—K1	3.9529 (7)	O8—Mo4A	1.708 (6)
Mo3—O3	1.714 (3)	O9—V4	1.916 (12)
Mo3—O7	1.708 (3)	O9—K3ⁱ	2.931 (9)
Mo3—O9ⁱ	2.322 (2)	O9—Mo4A	1.960 (6)
Mo3—O11	1.921 (2)	O9—K4ⁱ	3.105 (13)
Mo3—O12	1.966 (2)	O11—K3	2.994 (8)
Mo3—O13	2.275 (2)	O11—K4ⁱⁱ	3.232 (11)
Mo3—V4	3.134 (12)	O11—K4	2.986 (12)
Mo3—K3	3.682 (8)	O12—V4	1.916 (12)
Mo3—Mo4A	3.194 (6)	O12—Mo4A	1.956 (6)
Mo3—K4	3.665 (12)	O13—V4ⁱ	2.318 (9)
Mo3—K4ⁱⁱ	3.912 (13)	O13—V4	2.079 (11)
K1—K2ⁱⁱⁱ	3.8378 (10)	O13—Mo4A	2.185 (6)
K1—K2	3.8378 (10)	O13—Mo4Aⁱ	2.471 (5)
K1—O1ⁱⁱⁱ	2.722 (3)	O14S—K3^viii	2.879 (9)
K1—O1	2.722 (3)	O14S—K4^viii	3.125 (13)
K1—O2	2.715 (3)	O15S—K3	2.753 (8)
K1—O2ⁱⁱⁱ	2.715 (3)	O15S—K4	2.658 (11)
K1—O3ⁱⁱⁱ	2.703 (3)	K3—K3^ix	4.475 (16)
K1—O3	2.703 (3)	K3—O17S	2.808 (17)
K1—O4	2.767 (3)	K3—O17S^ix	2.42 (2)
K1—O4ⁱⁱⁱ	2.767 (3)	O17S—O17S^ix	1.06 (3)
K1—Mo4Aⁱⁱⁱ	3.913 (5)	K4—O16S	2.778 (15)
K1—Mo4A	3.913 (5)	O19S—O19S^ix	0.91 (5)

K2—Mo1—K1	58.044 (15)	Mo2—O2—K4ⁱⁱ	101.7 (2)
O1—Mo1—K1	32.49 (9)	K1—O2—K2	87.42 (8)
O1—Mo1—K2	46.95 (9)	K1—O2—K4ⁱⁱ	90.0 (2)
O1—Mo1—O9	98.07 (11)	K2—O2—K4ⁱⁱ	137.4 (2)
O1—Mo1—O10	100.05 (12)	Mo3—O3—K1	125.49 (13)
O1—Mo1—O12ⁱ	165.57 (11)	Mo3—O3—K3ⁱⁱ	103.63 (17)
O1—Mo1—O13	93.14 (11)	Mo3—O3—K3^vii	124.1 (2)
O1—Mo1—V4	87.91 (19)	Mo3—O3—K4ⁱⁱ	100.7 (2)
O1—Mo1—Mo4A	85.33 (11)	Mo3—O3—K4^vii	129.9 (3)
O5—Mo1—K1	137.65 (9)	K1—O3—K3^vii	106.62 (16)
O5—Mo1—K2	94.53 (9)	K1—O3—K3ⁱⁱ	93.86 (15)
O5—Mo1—O1	105.17 (13)	K1—O3—K4^vii	100.3 (2)
O5—Mo1—O9	98.78 (11)	K1—O3—K4ⁱⁱ	93.0 (2)
O5—Mo1—O10	101.84 (12)	K3^vii—O3—K3ⁱⁱ	90.5 (2)
O5—Mo1—O12ⁱ	87.84 (11)	K3^vii—O3—K4^vii	6.3 (3)
O5—Mo1—O13	161.28 (11)	K3^vii—O3—K4ⁱⁱ	94.93 (18)
O5—Mo1—V4	134.0 (2)	K1—O4—K2ⁱⁱⁱ	83.81 (7)
O5—Mo1—Mo4A	133.66 (14)	V4—O4—K1	122.2 (4)
O9—Mo1—K1	91.43 (7)	V4—O4—K2ⁱⁱⁱ	145.4 (4)
O9—Mo1—K2	144.89 (7)	Mo4A—O4—K1	125.1 (2)
O9—Mo1—O12ⁱ	73.34 (9)	Mo1—O5—K2^iv	156.25 (14)
O9—Mo1—O13	74.41 (9)	Mo2—O6—K2^v	134.22 (14)
O9—Mo1—V4	35.2 (2)	Mo3—O7—K2^x	147.76 (14)
O9—Mo1—Mo4A	34.96 (12)	Mo3—O7—K3	97.17 (17)
O10—Mo1—K1	89.77 (7)	Mo3—O7—K4	100.9 (2)
O10—Mo1—K2	57.24 (8)	K2^x—O7—K3	102.29 (16)
O10—Mo1—O9	147.81 (10)	K2^x—O7—K4	100.6 (2)
O10—Mo1—O12ⁱ	82.97 (10)	V4—O8—Mo2ⁱ	116.4 (3)
O10—Mo1—O13	78.22 (10)	Mo1—O9—Mo3ⁱ	101.88 (10)
O10—Mo1—V4	119.4 (2)	Mo1—O9—K3ⁱ	127.24 (18)
O10—Mo1—Mo4A	120.94 (12)	Mo1—O9—K4ⁱ	126.1 (2)
O12ⁱ—Mo1—K1	134.28 (6)	Mo3ⁱ—O9—K3ⁱ	88.20 (17)
O12ⁱ—Mo1—K2	139.81 (6)	Mo3ⁱ—O9—K4ⁱ	83.6 (2)
O12ⁱ—Mo1—O13	73.54 (9)	V4—O9—Mo1	108.3 (4)
O12ⁱ—Mo1—V4	78.41 (17)	V4—O9—Mo3ⁱ	108.1 (3)
O12ⁱ—Mo1—Mo4A	81.08 (10)	V4—O9—K3ⁱ	117.4 (3)
O13—Mo1—K1	60.80 (6)	V4—O9—K4ⁱ	120.9 (4)
O13—Mo1—K2	100.91 (6)	K3ⁱ—O9—K4ⁱ	5.0 (3)
O13—Mo1—V4	41.2 (2)	Mo4A—O9—Mo1	109.7 (2)
O13—Mo1—Mo4A	42.73 (11)	Mo1—O10—Mo2	115.99 (12)
V4—Mo1—K1	66.23 (19)	Mo1—O10—K2	93.43 (9)
V4—Mo1—K2	123.9 (2)	Mo2—O10—K2	91.18 (9)
Mo4A—Mo1—K1	64.40 (9)	Mo2—O11—Mo3	115.94 (13)
Mo4A—Mo1—K2	122.28 (9)	Mo2—O11—K3	130.77 (16)
K1—Mo2—K4ⁱⁱ	64.30 (17)	Mo2—O11—K4ⁱⁱ	101.0 (2)
K2—Mo2—K1	58.277 (18)	Mo2—O11—K4	135.48 (18)
K2—Mo2—K4ⁱⁱ	93.55 (18)	Mo3—O11—K3	94.50 (18)
O2—Mo2—K1	31.47 (9)	Mo3—O11—K4	94.2 (2)
O2—Mo2—K2	42.99 (9)	Mo3—O11—K4ⁱⁱ	95.4 (2)
O2—Mo2—O8ⁱ	162.74 (11)	K3—O11—K4ⁱⁱ	114.3 (3)
O2—Mo2—O10	96.00 (12)	Mo3—O12—Mo1ⁱ	103.41 (11)
O2—Mo2—O11	97.91 (12)	V4—O12—Mo1ⁱ	108.7 (3)
O2—Mo2—O13	91.59 (11)	V4—O12—Mo3	107.7 (4)
O2—Mo2—K4ⁱⁱ	53.7 (2)	Mo4A—O12—Mo3	109.0 (2)
O6—Mo2—K1	136.08 (9)	Mo1—O13—Mo2	86.88 (8)
O6—Mo2—K2	92.13 (10)	Mo1—O13—V4ⁱ	95.3 (3)
O6—Mo2—O2	104.67 (13)	Mo1—O13—Mo4Aⁱ	95.14 (16)
O6—Mo2—O8ⁱ	92.49 (11)	Mo2—O13—Mo4Aⁱ	88.62 (15)
O6—Mo2—O10	102.94 (12)	Mo3—O13—Mo1	166.46 (12)
O6—Mo2—O11	102.53 (12)	Mo3—O13—Mo2	87.26 (8)
O6—Mo2—O13	163.74 (11)	Mo3—O13—V4ⁱ	97.0 (3)
O6—Mo2—K4ⁱⁱ	88.7 (2)	Mo3—O13—Mo4Aⁱ	96.92 (16)
O8ⁱ—Mo2—K1	131.43 (7)	V4—O13—Mo1	91.6 (3)
O8ⁱ—Mo2—K2	136.17 (7)	V4ⁱ—O13—Mo2	90.4 (3)
O8ⁱ—Mo2—O13	71.26 (9)	V4—O13—Mo2	169.7 (3)
O8ⁱ—Mo2—K4ⁱⁱ	130.11 (19)	V4—O13—Mo3	92.0 (3)
O10—Mo2—K1	88.90 (8)	V4—O13—V4ⁱ	99.9 (3)
O10—Mo2—K2	58.54 (7)	V4—O13—Mo4Aⁱ	101.7 (4)
O10—Mo2—O8ⁱ	77.97 (10)	V4ⁱ—O13—Mo4Aⁱ	1.8 (4)
O10—Mo2—O13	74.85 (9)	Mo4A—O13—Mo1	91.30 (18)
O10—Mo2—K4ⁱⁱ	149.63 (19)	Mo4A—O13—Mo2	166.09 (17)
O11—Mo2—K1	87.44 (8)	Mo4A—O13—Mo3	91.45 (18)
O11—Mo2—K2	140.85 (8)	K2—O14S—K3^viii	114.69 (19)
O11—Mo2—O8ⁱ	79.85 (10)	K2—O14S—K4^viii	118.2 (2)
O11—Mo2—O10	146.71 (10)	K3^viii—O14S—K4^viii	3.8 (3)
O11—Mo2—O13	74.67 (9)	K3—O15S—K2^x	106.2 (2)
O11—Mo2—K4ⁱⁱ	51.45 (19)	Mo1—V4—K1	67.3 (2)
O13—Mo2—K1	60.17 (6)	Mo3—V4—Mo1	92.9 (3)
O13—Mo2—K2	99.99 (6)	Mo3—V4—K1	66.2 (2)
O13—Mo2—K4ⁱⁱ	101.21 (18)	O4—V4—Mo1	91.0 (5)
O3—Mo3—K1	33.83 (9)	O4—V4—Mo3	90.6 (5)
O3—Mo3—O9ⁱ	166.97 (11)	O4—V4—K1	36.0 (3)
O3—Mo3—O11	101.45 (11)	O4—V4—O8	100.0 (5)
O3—Mo3—O12	98.18 (11)	O4—V4—O9	99.2 (6)
O3—Mo3—O13	95.71 (11)	O4—V4—O12	99.7 (5)
O3—Mo3—V4	88.72 (19)	O4—V4—O13ⁱ	178.0 (7)
O3—Mo3—K3	139.46 (16)	O4—V4—O13	98.0 (6)
O3—Mo3—Mo4A	86.07 (12)	O8—V4—Mo1	132.5 (6)
O3—Mo3—K4ⁱⁱ	53.79 (19)	O8—V4—Mo3	132.6 (6)
O3—Mo3—K4	135.1 (2)	O8—V4—K1	136.0 (4)
O7—Mo3—K1	137.77 (9)	O8—V4—O9	96.0 (6)
O7—Mo3—O3	104.41 (13)	O8—V4—O12	95.9 (6)
O7—Mo3—O9ⁱ	86.95 (11)	O8—V4—O13	162.0 (5)
O7—Mo3—O11	96.69 (12)	O8—V4—O13ⁱ	82.0 (4)
O7—Mo3—O12	102.49 (11)	O9—V4—Mo1	36.5 (2)
O7—Mo3—O13	159.87 (11)	O9—V4—Mo3	127.9 (5)
O7—Mo3—V4	138.1 (2)	O9—V4—K1	93.3 (4)
O7—Mo3—K3	55.44 (13)	O9—V4—O13	81.4 (4)
O7—Mo3—Mo4A	137.85 (14)	O9—V4—O13ⁱ	80.0 (4)
O7—Mo3—K4ⁱⁱ	83.28 (18)	O12—V4—Mo1	127.8 (5)
O7—Mo3—K4	51.84 (15)	O12—V4—Mo3	36.7 (2)
O9ⁱ—Mo3—K1	135.28 (6)	O12—V4—K1	92.8 (4)
O9ⁱ—Mo3—V4	78.46 (17)	O12—V4—O9	155.5 (5)
O9ⁱ—Mo3—K3	52.73 (14)	O12—V4—O13ⁱ	80.6 (4)
O9ⁱ—Mo3—Mo4A	81.16 (9)	O12—V4—O13	80.7 (4)
O9ⁱ—Mo3—K4	57.34 (18)	O13ⁱ—V4—Mo1	87.3 (3)
O9ⁱ—Mo3—K4ⁱⁱ	135.58 (17)	O13—V4—Mo1	47.2 (2)
O11—Mo3—K1	89.63 (7)	O13—V4—Mo3	46.5 (2)
O11—Mo3—O9ⁱ	83.21 (9)	O13ⁱ—V4—Mo3	88.5 (3)
O11—Mo3—O12	148.10 (10)	O13ⁱ—V4—K1	142.1 (4)
O11—Mo3—O13	78.38 (10)	O13—V4—K1	62.0 (3)
O11—Mo3—V4	119.9 (2)	O13—V4—O13ⁱ	80.1 (3)
O11—Mo3—K3	54.17 (14)	Mo3—K3—Mo3^xi	166.9 (2)
O11—Mo3—Mo4A	121.51 (12)	Mo3^xi—K3—K3^ix	57.71 (14)
O11—Mo3—K4	54.33 (19)	Mo3—K3—K3^ix	125.6 (3)
O11—Mo3—K4ⁱⁱ	55.33 (15)	O3^xi—K3—Mo3^xi	20.28 (8)
O12—Mo3—K1	92.94 (7)	O3ⁱⁱ—K3—Mo3^xi	75.30 (16)
O12—Mo3—O9ⁱ	72.73 (9)	O3^xi—K3—Mo3	172.1 (3)
O12—Mo3—O13	74.84 (9)	O3ⁱⁱ—K3—Mo3	115.8 (2)
O12—Mo3—V4	35.6 (2)	O3^xi—K3—O3ⁱⁱ	56.36 (18)
O12—Mo3—K3	119.32 (15)	O3^xi—K3—O7	150.6 (2)
O12—Mo3—Mo4A	35.39 (13)	O3^xi—K3—O9ⁱ	148.3 (3)
O12—Mo3—K4ⁱⁱ	151.67 (18)	O3^xi—K3—O11	143.1 (3)
O12—Mo3—K4	122.2 (2)	O3^xi—K3—K3^ix	49.39 (13)
O13—Mo3—K1	62.19 (6)	O3ⁱⁱ—K3—K3^ix	40.13 (14)
O13—Mo3—O9ⁱ	73.14 (9)	O7—K3—Mo3^xi	158.6 (2)
O13—Mo3—V4	41.5 (2)	O7—K3—Mo3	27.39 (9)
O13—Mo3—K3	107.87 (11)	O7—K3—O3ⁱⁱ	110.4 (2)
O13—Mo3—Mo4A	43.15 (11)	O7—K3—K3^ix	139.5 (3)
O13—Mo3—K4ⁱⁱ	108.73 (15)	O9ⁱ—K3—Mo3	39.07 (11)
O13—Mo3—K4	112.15 (12)	O9ⁱ—K3—Mo3^xi	128.1 (2)
V4—Mo3—K1	67.24 (19)	O9ⁱ—K3—O3ⁱⁱ	150.1 (3)
V4—Mo3—K3	130.6 (2)	O9ⁱ—K3—O7	55.89 (16)
V4—Mo3—K4ⁱⁱ	133.3 (3)	O9ⁱ—K3—O11	57.11 (17)
K3—Mo3—K1	143.60 (13)	O9ⁱ—K3—K3^ix	130.75 (13)
K3—Mo3—K4ⁱⁱ	87.0 (2)	O11—K3—Mo3^xi	148.1 (2)
Mo4A—Mo3—K1	65.40 (9)	O11—K3—Mo3	31.33 (9)
Mo4A—Mo3—K4	138.23 (18)	O11—K3—O3ⁱⁱ	93.1 (2)
K4ⁱⁱ—Mo3—K1	66.35 (18)	O11—K3—O7	53.30 (15)
K4—Mo3—K1	142.8 (2)	O11—K3—K3^ix	94.3 (2)
K2—K1—K2ⁱⁱⁱ	117.00 (4)	O14S^xii—K3—Mo3	104.8 (3)
K2ⁱⁱⁱ—K1—Mo4Aⁱⁱⁱ	107.15 (7)	O14S^xii—K3—Mo3^xi	64.19 (16)
K2ⁱⁱⁱ—K1—Mo4A	68.57 (6)	O14S^xii—K3—O3ⁱⁱ	139.4 (3)
K2—K1—Mo4Aⁱⁱⁱ	68.57 (6)	O14S^xii—K3—O3^xi	83.1 (2)
K2—K1—Mo4A	107.15 (8)	O14S^xii—K3—O7	106.5 (3)
O1ⁱⁱⁱ—K1—K2	80.20 (6)	O14S^xii—K3—O9ⁱ	67.8 (2)
O1—K1—K2ⁱⁱⁱ	80.20 (6)	O14S^xii—K3—O11	123.0 (3)
O1—K1—K2	50.89 (6)	O14S^xii—K3—K3^ix	112.2 (3)
O1ⁱⁱⁱ—K1—K2ⁱⁱⁱ	50.89 (6)	O15S—K3—Mo3	98.1 (2)
O1—K1—O1ⁱⁱⁱ	79.89 (11)	O15S—K3—Mo3^xi	85.0 (2)
O1—K1—O4	69.33 (8)	O15S—K3—O3ⁱⁱ	105.0 (2)
O1—K1—O4ⁱⁱⁱ	98.31 (8)	O15S—K3—O3^xi	84.4 (2)
O1ⁱⁱⁱ—K1—O4	98.31 (8)	O15S—K3—O7	73.55 (18)
O1ⁱⁱⁱ—K1—O4ⁱⁱⁱ	69.33 (8)	O15S—K3—O9ⁱ	96.4 (3)
O1ⁱⁱⁱ—K1—Mo4Aⁱⁱⁱ	61.13 (10)	O15S—K3—O11	126.8 (3)
O1—K1—Mo4Aⁱⁱⁱ	112.29 (9)	O15S—K3—O14S^xii	69.8 (2)
O1ⁱⁱⁱ—K1—Mo4A	112.29 (9)	O15S—K3—K3^ix	131.1 (2)
O1—K1—Mo4A	61.13 (10)	O15S—K3—O17S	159.8 (5)
O2—K1—K2	47.61 (6)	O17S^ix—K3—Mo3^xi	65.9 (4)
O2ⁱⁱⁱ—K1—K2	149.41 (6)	O17S^ix—K3—Mo3	109.3 (4)
O2ⁱⁱⁱ—K1—K2ⁱⁱⁱ	47.61 (6)	O17S—K3—Mo3^xi	79.9 (5)
O2—K1—K2ⁱⁱⁱ	149.41 (6)	O17S—K3—Mo3	99.6 (5)
O2—K1—O1	70.28 (8)	O17S^ix—K3—O3ⁱⁱ	72.6 (5)
O2—K1—O1ⁱⁱⁱ	127.70 (8)	O17S^ix—K3—O3^xi	69.8 (4)
O2ⁱⁱⁱ—K1—O1	127.70 (8)	O17S—K3—O3^xi	76.7 (5)
O2ⁱⁱⁱ—K1—O1ⁱⁱⁱ	70.27 (8)	O17S—K3—O3ⁱⁱ	58.1 (3)
O2—K1—O2ⁱⁱⁱ	159.41 (12)	O17S^ix—K3—O7	135.4 (5)
O2—K1—O4ⁱⁱⁱ	73.65 (8)	O17S—K3—O7	121.0 (5)
O2—K1—O4	109.28 (8)	O17S^ix—K3—O9ⁱ	98.4 (4)
O2ⁱⁱⁱ—K1—O4ⁱⁱⁱ	109.28 (8)	O17S—K3—O9ⁱ	103.5 (4)
O2ⁱⁱⁱ—K1—O4	73.65 (8)	O17S—K3—O11	68.9 (5)
O2—K1—Mo4Aⁱⁱⁱ	91.66 (8)	O17S^ix—K3—O11	82.4 (4)
O2ⁱⁱⁱ—K1—Mo4A	91.66 (8)	O17S—K3—O14S^xii	114.4 (4)
O2ⁱⁱⁱ—K1—Mo4Aⁱⁱⁱ	89.73 (8)	O17S^ix—K3—O14S^xii	92.7 (5)
O2—K1—Mo4A	89.73 (8)	O17S^ix—K3—O15S	150.6 (5)
O3—K1—K2ⁱⁱⁱ	110.69 (6)	O17S^ix—K3—K3^ix	33.9 (4)
O3ⁱⁱⁱ—K1—K2	110.69 (6)	O17S—K3—K3^ix	28.7 (4)
O3ⁱⁱⁱ—K1—K2ⁱⁱⁱ	121.05 (6)	O17S^ix—K3—O17S	21.9 (7)
O3—K1—K2	121.05 (6)	K3^ix—O17S—K3	117.4 (8)
O3—K1—O1	110.17 (7)	O17S^ix—O17S—K3	58.3 (17)
O3ⁱⁱⁱ—K1—O1ⁱⁱⁱ	110.17 (7)	O17S^ix—O17S—K3^ix	100 (2)
O3—K1—O1ⁱⁱⁱ	158.51 (8)	Mo1—Mo4A—K1	67.71 (10)
O3ⁱⁱⁱ—K1—O1	158.51 (8)	Mo3—Mo4A—Mo1	90.58 (13)
O3ⁱⁱⁱ—K1—O2ⁱⁱⁱ	73.73 (8)	Mo3—Mo4A—K1	66.70 (10)
O3—K1—O2	73.73 (8)	O4—Mo4A—Mo1	91.5 (2)
O3ⁱⁱⁱ—K1—O2	89.02 (8)	O4—Mo4A—Mo3	91.2 (2)
O3—K1—O2ⁱⁱⁱ	89.02 (8)	O4—Mo4A—K1	35.35 (17)
O3—K1—O3ⁱⁱⁱ	67.44 (11)	O4—Mo4A—O8	108.3 (3)
O3—K1—O4	69.37 (8)	O4—Mo4A—O9	102.8 (3)
O3—K1—O4ⁱⁱⁱ	125.33 (8)	O4—Mo4A—O12	103.5 (3)
O3ⁱⁱⁱ—K1—O4	125.33 (8)	O4—Mo4A—O13	98.7 (3)
O3ⁱⁱⁱ—K1—O4ⁱⁱⁱ	69.37 (8)	O4—Mo4A—O13ⁱ	173.3 (3)
O3—K1—Mo4Aⁱⁱⁱ	126.58 (10)	O8—Mo4A—Mo1	131.1 (3)
O3ⁱⁱⁱ—K1—Mo4Aⁱⁱⁱ	61.08 (10)	O8—Mo4A—Mo3	131.5 (3)
O3ⁱⁱⁱ—K1—Mo4A	126.58 (10)	O8—Mo4A—K1	143.64 (18)
O3—K1—Mo4A	61.08 (10)	O8—Mo4A—O9	95.9 (3)
O4—K1—K2ⁱⁱⁱ	50.41 (6)	O8—Mo4A—O12	96.0 (3)
O4ⁱⁱⁱ—K1—K2	50.41 (6)	O8—Mo4A—O13	153.0 (2)
O4ⁱⁱⁱ—K1—K2ⁱⁱⁱ	119.69 (6)	O8—Mo4A—O13ⁱ	78.3 (2)
O4—K1—K2	119.69 (6)	O9—Mo4A—Mo1	35.29 (12)
O4ⁱⁱⁱ—K1—O4	164.38 (12)	O9—Mo4A—Mo3	123.1 (2)
O4—K1—Mo4A	19.56 (8)	O9—Mo4A—K1	94.7 (2)
O4ⁱⁱⁱ—K1—Mo4Aⁱⁱⁱ	19.56 (8)	O9—Mo4A—O13	77.8 (2)
O4ⁱⁱⁱ—K1—Mo4A	157.51 (9)	O9—Mo4A—O13ⁱ	75.38 (16)
O4—K1—Mo4Aⁱⁱⁱ	157.51 (9)	O12—Mo4A—Mo1	122.9 (2)
Mo4Aⁱⁱⁱ—K1—Mo4A	172.26 (17)	O12—Mo4A—Mo3	35.59 (12)
Mo2—K2—Mo1	49.905 (12)	O12—Mo4A—K1	94.3 (2)
K1—K2—Mo1	62.579 (15)	O12—Mo4A—O9	145.9 (2)
K1—K2—Mo2	63.312 (16)	O12—Mo4A—O13	77.1 (2)
O1—K2—Mo1	24.92 (5)	O12—Mo4A—O13ⁱ	75.99 (17)
O1—K2—Mo2	63.71 (5)	O13ⁱ—Mo4A—Mo1	83.42 (13)
O1—K2—K1	44.89 (5)	O13—Mo4A—Mo1	45.97 (12)
O1—K2—O10	52.56 (7)	O13ⁱ—Mo4A—Mo3	84.57 (14)
O2—K2—Mo1	62.00 (5)	O13—Mo4A—Mo3	45.40 (12)
O2—K2—Mo2	24.46 (5)	O13ⁱ—Mo4A—K1	138.03 (18)
O2—K2—K1	44.97 (6)	O13—Mo4A—K1	63.32 (14)
O2—K2—O1	64.86 (8)	O13—Mo4A—O13ⁱ	74.71 (14)
O2—K2—O4ⁱⁱⁱ	68.80 (8)	Mo3—K4—Mo3ⁱⁱ	96.7 (3)
O2—K2—O10	52.30 (7)	O2ⁱⁱ—K4—Mo3ⁱⁱ	59.19 (19)
O2—K2—O15S^vi	86.06 (9)	O2ⁱⁱ—K4—Mo3	111.9 (2)
O4ⁱⁱⁱ—K2—Mo1	108.35 (5)	O3ⁱⁱ—K4—Mo3ⁱⁱ	25.51 (11)
O4ⁱⁱⁱ—K2—Mo2	93.26 (6)	O3ⁱⁱ—K4—Mo3	121.3 (4)
O4ⁱⁱⁱ—K2—K1	45.79 (5)	O3^xi—K4—Mo3	172.7 (3)
O4ⁱⁱⁱ—K2—O1	88.19 (7)	O3^xi—K4—Mo3ⁱⁱ	83.8 (3)
O4ⁱⁱⁱ—K2—O10	117.95 (7)	O3ⁱⁱ—K4—O2ⁱⁱ	59.5 (2)
O5^iv—K2—Mo1	61.84 (6)	O3^xi—K4—O2ⁱⁱ	74.6 (3)
O5^iv—K2—Mo2	102.31 (6)	O3^xi—K4—O3ⁱⁱ	58.5 (3)
O5^iv—K2—K1	114.02 (6)	O3^xi—K4—O7	160.0 (3)
O5^iv—K2—O1	70.23 (8)	O3^xi—K4—O9ⁱ	137.5 (4)
O5^iv—K2—O2	122.24 (8)	O3ⁱⁱ—K4—O11ⁱⁱ	51.8 (2)
O5^iv—K2—O4ⁱⁱⁱ	143.49 (9)	O3^xi—K4—O11	142.8 (4)
O5^iv—K2—O6^v	136.32 (8)	O3^xi—K4—O11ⁱⁱ	105.0 (4)
O5^iv—K2—O10	72.03 (7)	O3^xi—K4—O14S^xii	78.7 (3)
O5^iv—K2—O14S	73.66 (10)	O7—K4—Mo3ⁱⁱ	94.4 (3)
O5^iv—K2—O15S^vi	77.67 (9)	O7—K4—Mo3	27.22 (12)
O6^v—K2—Mo1	155.66 (7)	O7—K4—O2ⁱⁱ	87.35 (18)
O6^v—K2—Mo2	105.79 (6)	O7—K4—O3ⁱⁱ	119.2 (4)
O6^v—K2—K1	108.31 (6)	O7—K4—O9ⁱ	55.3 (2)
O6^v—K2—O1	153.12 (8)	O7—K4—O11	54.6 (2)
O6^v—K2—O2	95.19 (8)	O7—K4—O11ⁱⁱ	67.7 (2)
O6^v—K2—O4ⁱⁱⁱ	67.03 (8)	O7—K4—O14S^xii	103.4 (4)
O6^v—K2—O10	129.77 (8)	O9ⁱ—K4—Mo3ⁱⁱ	132.2 (4)
O6^v—K2—O15S^vi	83.98 (9)	O9ⁱ—K4—Mo3	39.02 (15)
O7^vi—K2—Mo1	125.19 (6)	O9ⁱ—K4—O2ⁱⁱ	138.7 (3)
O7^vi—K2—Mo2	143.61 (7)	O9ⁱ—K4—O3ⁱⁱ	151.0 (4)
O7^vi—K2—K1	152.55 (7)	O9ⁱ—K4—O11ⁱⁱ	117.1 (4)
O7^vi—K2—O1	129.86 (8)	O9ⁱ—K4—O14S^xii	62.7 (3)
O7^vi—K2—O2	161.39 (9)	O11ⁱⁱ—K4—Mo3ⁱⁱ	29.26 (12)
O7^vi—K2—O4ⁱⁱⁱ	118.29 (8)	O11—K4—Mo3ⁱⁱ	77.1 (3)
O7^vi—K2—O5^iv	63.61 (8)	O11—K4—Mo3	31.51 (13)
O7^vi—K2—O6^v	73.99 (8)	O11ⁱⁱ—K4—Mo3	78.1 (2)
O7^vi—K2—O10	123.76 (8)	O11—K4—O2ⁱⁱ	119.4 (3)
O7^vi—K2—O14S	72.25 (10)	O11ⁱⁱ—K4—O2ⁱⁱ	49.33 (15)
O7^vi—K2—O15S^vi	77.89 (9)	O11—K4—O3ⁱⁱ	97.1 (4)
O10—K2—Mo1	29.34 (4)	O11—K4—O9ⁱ	55.4 (2)
O10—K2—Mo2	30.28 (4)	O11—K4—O11ⁱⁱ	71.7 (3)
O10—K2—K1	76.74 (5)	O11—K4—O14S^xii	115.3 (4)
O14S—K2—Mo1	97.10 (9)	O14S^xii—K4—Mo3	100.2 (3)
O14S—K2—Mo2	139.00 (9)	O14S^xii—K4—Mo3ⁱⁱ	162.1 (4)
O14S—K2—K1	80.82 (8)	O14S^xii—K4—O2ⁱⁱ	118.6 (4)
O14S—K2—O1	77.14 (10)	O14S^xii—K4—O3ⁱⁱ	136.6 (4)
O14S—K2—O2	125.79 (10)	O14S^xii—K4—O11ⁱⁱ	163.5 (3)
O14S—K2—O4ⁱⁱⁱ	72.99 (9)	O15S—K4—Mo3ⁱⁱ	115.5 (3)
O14S—K2—O6^v	103.78 (11)	O15S—K4—Mo3	100.4 (3)
O14S—K2—O10	126.00 (10)	O15S—K4—O2ⁱⁱ	56.71 (18)
O14S—K2—O15S^vi	145.39 (11)	O15S—K4—O3^xi	85.9 (4)
O15S^vi—K2—Mo1	85.92 (7)	O15S—K4—O3ⁱⁱ	112.7 (4)
O15S^vi—K2—Mo2	66.07 (7)	O15S—K4—O7	76.9 (3)
O15S^vi—K2—K1	129.36 (8)	O15S—K4—O9ⁱ	94.4 (4)
O15S^vi—K2—O1	110.82 (9)	O15S—K4—O11ⁱⁱ	96.8 (2)
O15S^vi—K2—O4ⁱⁱⁱ	138.64 (9)	O15S—K4—O11	131.2 (4)
O15S^vi—K2—O10	59.81 (8)	O15S—K4—O14S^xii	67.2 (3)
Mo1—O1—K1	127.60 (13)	O15S—K4—O16S	154.6 (5)
Mo1—O1—K2	108.13 (12)	O16S—K4—Mo3	100.0 (4)
K1—O1—K2	84.23 (7)	O16S—K4—O7	126.0 (5)
Mo2—O2—K1	129.18 (12)	O16S—K4—O11	71.7 (4)
Mo2—O2—K2	112.55 (12)	K4^ix—O16S—K4	108.9 (10)

Symmetry codes: (i) −x+3/2, −y+1/2, −z+2; (ii) −x+1, −y, −z+2; (iii) −x+1, y, −z+3/2; (iv) −x+1, −y+1, −z+2; (v) −x+1/2, −y+1/2, −z+2; (vi) x−1/2, y+1/2, z; (vii) x, −y, z−1/2; (viii) x−1/2, −y+1/2, z−1/2; (ix) −x+1, y, −z+5/2; (x) x+1/2, y−1/2, z; (xi) x, −y, z+1/2; (xii) x+1/2, −y+1/2, z+1/2.

Acknowledgements

The authors are grateful to ao.Univ.-Prof. Mag. Dr. Markus Galanski (Universität Wien, Austria) for NMR measurements and Dr Marek Bujdoš (Comenius University in Bratislava, Slovakia) for elemental analyses.

Funding information

Funding for this research was provided by: Austrian Science Fund (FWF, grant No. M2200 to LK; award No. P27534 to AR); University of Vienna (contract to AR).

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