Bis­[4,4′-bipyridinium(2+)] hexacosaoxooctamolybdate

Wu, C.-D.; Lu, C.-Z.; Zhuang, H.-H.; Huang, J.-S.

doi:10.1107/S1600536801010546

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Bis[4,4′-bipyridinium(2+)] hexacosaoxooctamolybdate

C.-D. Wu, C.-Z. Lu, H.-H. Zhuang and J.-S. Huang

The title compound, (C₁₀H₁₀N₂)₂[Mo₈O₂₆], was produced by hydrothermal reaction of an acidified aqueous solution of H₂MoO₄, 4,4′-bipyridine and NiCl₂·6H₂O. The structure of the title compound consists of the β-octamolybdate anion having a center of symmetry and protonated 4,4′-bipyridine cations. The distances between Mo and O atoms shared by two or more neighboring {MoO₆} octahedra are in the range 1.750 (2)–2.450 (2) Å and those between Mo and terminal O atoms in the range 1.696 (3)–1.720 (3) Å. The N—H

O hydrogen-bond lengths are in the range 2.722 (4)-2.755 (4) Å.

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Supporting information

	Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536801010546/ob6052sup1.cif Contains datablocks I, new
	Structure factor file (CIF format) https://doi.org/10.1107/S1600536801010546/ob6052Isup2.hkl Contains datablock I

CCDC reference: 170867

checkCIF report

Key indicators

Single-crystal X-ray study
T = 293 K
Mean (C-C) = 0.005 Å
R factor = 0.022
wR factor = 0.054
Data-to-parameter ratio = 10.1

checkCIF results

No syntax errors found

ADDSYM reports no extra symmetry


 Alert Level C:



PLAT_702  Alert C Angle   Calc    77.35(8), Rep   77.50(10), Dev.      1.88 Sigma
                     O13  -MO4  -O8      1.555   1.555   3.656


 0 Alert Level A = Potentially serious problem

 0 Alert Level B = Potential problem

 1 Alert Level C = Please check

Comment top

One of the interesting aspects of octamolybdates, [Mo₈O₂₆]^4-, is that they exhibit various structural patterns (Xi et al., 1994). Up to now, a series of octamolybdates have been reported in the literature; the structures of the α-, β-, γ, α–γ-, β–γ-, ε- and ξ-[Mo₈O₂₆]^4- isomers had been studied in great detail (Day et al., 1977; Hagrman et al., 1999; Lindgvist, 1950; Pope, 1983; Xi et al., 1994; Xu et al., 1999). In the course of our interest in the synthesis of 4,4'-bipyridine-bridged heterometallic polymers, the title compound, (I), was obtained as a single-crystal.

As shown in Fig. 1, the octamolybdate anion is built up of eight edge-shared {MoO₆} octahedra. It can also be described as that two centrosymmetric related cyclic {Mo₄O₁₃} units are crosslinked by bridging O atoms. The coordination environment of each Mo atom is a distorted octahedron, with Mo—O distances ranging from 1.696 (3) to 2.450 (2) Å and angles involving the neighboring O atoms ranging from 69.7 (1) to 104.8 (1)°. According to the coordinating mode, the O atoms in the anion can be divided into four different groups, which are terminal O atoms [Mo—O = 1.696 (3)–1.720 (2) Å], µ₂-O atoms [Mo—O = 1.750 (2)–2.299 (3) Å], µ₃-O atoms [Mo—O = 1.954 (2)–2.388 (2) Å] and µ₅-O atoms [Mo—O = 2.155 (2)–2.450 (2) Å]. N—H···O hydrogen bonding exists in the packing of the title compound (Table 2 and Fig. 2).

Experimental top

The title compound, (I), was prepared by hydrothermal synthesis from a mixture of H₂MoO₄ (0.10 g, 0.62 mmol), NiCl₂^.6H₂O (0.10 g, 0.42 mmol), 4,4'-bipyridine^.2H₂O (0.05 g, 0.26 mmol) and 65%wt HNO₃ (0.1 ml, 1.5 mmol) in H₂O (18 ml) was heated at 443 K for 6 d under autogeneous pressure. After the reaction mixture had been slowly cooled to room temperature, colorless crystals of (I) appeared.

Computing details top

Data collection: SMART (Siemens, 1996); cell refinement: SMART and SAINT (Siemens, 1994); data reduction: SMART and SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXL97; software used to prepare material for publication: SHELXL97.

Figures top

	Fig. 1. The structure of the β-[Mo₈O₂₆]^4- anion.
	Fig. 2. Packing diagram viewed down the c axis.

Di-4,4'-bipridine Hexacosaoxooctamolybdate top

Crystal data top

(C₁₀H₁₀N₂)[Mo₈O₂₆]	F(000) = 1424
M_r = 1499.92	D_x = 2.829 Mg m⁻³
Monoclinic, P2₁/n	Mo Kα radiation, λ = 0.71073 Å
a = 10.7493 (2) Å	Cell parameters from 5475 reflections
b = 15.2255 (1) Å	θ = 2.3–25.0°
c = 10.7828 (2) Å	µ = 2.86 mm⁻¹
β = 93.840 (1)°	T = 293 K
V = 1760.79 (5) Å³	Prism, colorless
Z = 2	0.39 × 0.32 × 0.28 mm

Data collection top

SMART CCD diffractometer	3065 independent reflections
Radiation source: fine-focus sealed tube	2781 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.017
ϕ and ω scans	θ_max = 25.0°, θ_min = 2.3°
Absorption correction: empirical (using intensity measurements) (SADABS; Sheldrick, 1996)	h = −12→12
T_min = 0.329, T_max = 0.449	k = −18→14
6344 measured reflections	l = −10→12

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.022	All H-atom parameters refined
wR(F²) = 0.054	w = 1/[σ²(F_o²) + (0.0222P)² + 2.4922P] where P = (F_o² + 2F_c²)/3
S = 1.09	(Δ/σ)_max < 0.001
3065 reflections	Δρ_max = 0.46 e Å⁻³
303 parameters	Δρ_min = −0.67 e Å⁻³
0 restraints	Extinction correction: SHELXL97, Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.00224 (12)

Crystal data top

(C₁₀H₁₀N₂)[Mo₈O₂₆]	V = 1760.79 (5) Å³
M_r = 1499.92	Z = 2
Monoclinic, P2₁/n	Mo Kα radiation
a = 10.7493 (2) Å	µ = 2.86 mm⁻¹
b = 15.2255 (1) Å	T = 293 K
c = 10.7828 (2) Å	0.39 × 0.32 × 0.28 mm
β = 93.840 (1)°

Data collection top

SMART CCD diffractometer	3065 independent reflections
Absorption correction: empirical (using intensity measurements) (SADABS; Sheldrick, 1996)	2781 reflections with I > 2σ(I)
T_min = 0.329, T_max = 0.449	R_int = 0.017
6344 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.022	0 restraints
wR(F²) = 0.054	All H-atom parameters refined
S = 1.09	Δρ_max = 0.46 e Å⁻³
3065 reflections	Δρ_min = −0.67 e Å⁻³
303 parameters

Special details top

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

Refinement. Refinement of F² against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F², conventional R-factors R are based on F, with F set to zero for negative F². The threshold expression of F² > σ(F²) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F² are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

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

	x	y	z	U_iso*/U_eq
Mo1	0.24215 (3)	0.023975 (19)	0.41069 (3)	0.02040 (10)
Mo2	0.49830 (3)	0.04076 (2)	0.24051 (3)	0.02049 (10)
Mo3	0.74812 (3)	0.13054 (2)	0.37742 (3)	0.02391 (10)
Mo4	0.48690 (3)	0.111430 (18)	0.55018 (3)	0.01793 (9)
O1	0.8145 (3)	0.23319 (18)	0.3771 (3)	0.0371 (7)
O2	0.6001 (2)	0.18415 (15)	0.5019 (2)	0.0255 (5)
O3	0.8360 (3)	0.0692 (2)	0.2848 (3)	0.0398 (7)
O4	0.8088 (2)	0.08878 (16)	0.5374 (2)	0.0262 (5)
O5	0.1696 (2)	0.03081 (18)	0.2654 (2)	0.0312 (6)
O6	0.6027 (2)	0.14074 (16)	0.2637 (2)	0.0273 (6)
O7	0.5918 (2)	−0.02641 (18)	0.1584 (2)	0.0319 (6)
O8	0.3938 (2)	−0.01284 (15)	0.5680 (2)	0.0207 (5)
O9	0.1606 (2)	0.09296 (18)	0.4989 (2)	0.0314 (6)
O10	0.5944 (2)	0.05457 (15)	0.6800 (2)	0.0213 (5)
O11	0.3892 (2)	0.08031 (18)	0.1323 (2)	0.0318 (6)
O12	0.3941 (2)	0.17446 (17)	0.6351 (2)	0.0302 (6)
O13	0.3878 (2)	0.10446 (14)	0.3918 (2)	0.0190 (5)
N1	1.0597 (3)	0.2744 (2)	0.3644 (3)	0.0311 (7)
H1A	0.975 (4)	0.259 (3)	0.363 (4)	0.033 (11)*
N2	1.6812 (3)	0.4010 (2)	0.3882 (3)	0.0346 (8)
H2A	1.759 (5)	0.418 (3)	0.390 (4)	0.048 (14)*
C1	1.2236 (4)	0.3560 (3)	0.4613 (4)	0.0373 (10)
H1	1.250 (5)	0.395 (3)	0.524 (5)	0.055 (15)*
C2	1.1005 (4)	0.3301 (3)	0.4530 (4)	0.0417 (11)
H2	1.045 (5)	0.355 (3)	0.503 (5)	0.056 (15)*
C3	1.4368 (3)	0.3526 (2)	0.3800 (3)	0.0229 (7)
C4	1.1335 (4)	0.2423 (3)	0.2821 (4)	0.0323 (9)
H4	1.099 (4)	0.205 (3)	0.228 (4)	0.034 (12)*
C5	1.2561 (4)	0.2665 (2)	0.2850 (4)	0.0277 (8)
H5	1.302 (4)	0.245 (2)	0.231 (4)	0.021 (10)*
C6	1.3038 (3)	0.3250 (2)	0.3758 (3)	0.0240 (7)
C7	1.5028 (4)	0.3510 (3)	0.2738 (4)	0.0331 (9)
H7	1.465 (4)	0.335 (3)	0.193 (4)	0.034 (11)*
C8	1.6268 (4)	0.3754 (3)	0.2801 (4)	0.0368 (10)
H8	1.689 (5)	0.371 (3)	0.213 (6)	0.071 (17)*
C9	1.4982 (4)	0.3808 (2)	0.4910 (4)	0.0271 (8)
H9	1.458 (4)	0.382 (2)	0.561 (4)	0.022 (10)*
C10	1.6208 (4)	0.4047 (3)	0.4929 (4)	0.0334 (9)
H10	1.668 (4)	0.425 (3)	0.568 (4)	0.042 (12)*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Mo1	0.01509 (16)	0.02654 (17)	0.01941 (17)	0.00040 (11)	−0.00014 (12)	0.00269 (12)
Mo2	0.01621 (16)	0.03073 (17)	0.01461 (16)	0.00070 (12)	0.00170 (12)	0.00145 (12)
Mo3	0.01748 (17)	0.02918 (17)	0.02513 (18)	−0.00308 (12)	0.00193 (13)	0.00564 (13)
Mo4	0.01682 (16)	0.01970 (16)	0.01713 (16)	0.00114 (11)	0.00008 (12)	−0.00167 (11)
O1	0.0270 (14)	0.0361 (15)	0.0480 (18)	−0.0071 (12)	0.0015 (13)	0.0106 (13)
O2	0.0253 (13)	0.0233 (12)	0.0276 (14)	−0.0016 (10)	0.0009 (11)	0.0001 (10)
O3	0.0290 (15)	0.0546 (18)	0.0363 (17)	0.0054 (13)	0.0064 (13)	0.0013 (14)
O4	0.0205 (13)	0.0298 (13)	0.0277 (14)	−0.0052 (10)	−0.0033 (10)	0.0039 (11)
O5	0.0245 (14)	0.0435 (15)	0.0250 (14)	−0.0016 (11)	−0.0033 (11)	0.0057 (11)
O6	0.0249 (14)	0.0333 (13)	0.0236 (14)	−0.0031 (11)	−0.0001 (11)	0.0078 (11)
O7	0.0232 (14)	0.0474 (16)	0.0257 (14)	0.0048 (12)	0.0052 (11)	−0.0034 (12)
O8	0.0189 (12)	0.0244 (12)	0.0186 (12)	0.0000 (9)	0.0004 (9)	−0.0003 (10)
O9	0.0262 (14)	0.0389 (14)	0.0296 (15)	0.0042 (12)	0.0044 (11)	−0.0019 (12)
O10	0.0201 (12)	0.0246 (12)	0.0188 (12)	−0.0012 (10)	−0.0013 (10)	−0.0013 (10)
O11	0.0238 (14)	0.0478 (16)	0.0234 (14)	0.0035 (12)	0.0000 (11)	0.0056 (12)
O12	0.0271 (14)	0.0346 (14)	0.0289 (14)	0.0049 (11)	0.0005 (11)	−0.0072 (11)
O13	0.0176 (12)	0.0225 (11)	0.0166 (12)	−0.0001 (9)	−0.0004 (9)	0.0022 (9)
N1	0.0194 (16)	0.0359 (17)	0.038 (2)	−0.0052 (14)	0.0000 (14)	0.0063 (15)
N2	0.0193 (17)	0.0386 (18)	0.046 (2)	−0.0035 (14)	0.0043 (16)	0.0070 (16)
C1	0.025 (2)	0.055 (3)	0.032 (2)	−0.0056 (19)	0.0032 (17)	−0.013 (2)
C2	0.026 (2)	0.065 (3)	0.035 (2)	−0.001 (2)	0.0081 (19)	−0.011 (2)
C3	0.0202 (18)	0.0254 (17)	0.0227 (18)	0.0026 (14)	−0.0008 (14)	0.0040 (14)
C4	0.032 (2)	0.0276 (19)	0.035 (2)	−0.0012 (17)	−0.0088 (18)	−0.0027 (18)
C5	0.027 (2)	0.0296 (19)	0.027 (2)	0.0059 (16)	0.0009 (16)	−0.0013 (16)
C6	0.0196 (17)	0.0267 (18)	0.0251 (19)	0.0013 (14)	−0.0024 (14)	0.0036 (15)
C7	0.027 (2)	0.046 (2)	0.025 (2)	0.0010 (17)	0.0010 (17)	0.0031 (18)
C8	0.029 (2)	0.050 (2)	0.033 (2)	0.0014 (18)	0.0106 (18)	0.0080 (19)
C9	0.0248 (19)	0.0319 (19)	0.025 (2)	−0.0008 (15)	0.0022 (16)	0.0008 (16)
C10	0.026 (2)	0.036 (2)	0.037 (2)	−0.0034 (17)	−0.0043 (18)	0.0023 (19)

Geometric parameters (Å, º) top

Mo1—O9	1.700 (3)	O8—Mo3ⁱ	2.450 (2)
Mo1—O5	1.705 (3)	O10—Mo2ⁱ	1.987 (2)
Mo1—O4ⁱ	1.898 (2)	O10—Mo1ⁱ	2.388 (2)
Mo1—O13	2.009 (2)	N1—C4	1.324 (5)
Mo1—O8	2.341 (2)	N1—C2	1.330 (6)
Mo1—O10ⁱ	2.388 (2)	N1—H1A	0.93 (4)
Mo2—O11	1.707 (2)	N2—C8	1.328 (6)
Mo2—O7	1.720 (3)	N2—C10	1.341 (6)
Mo2—O6	1.898 (2)	N2—H2A	0.88 (5)
Mo2—O10ⁱ	1.987 (2)	C1—C2	1.377 (6)
Mo2—O13	2.297 (2)	C1—C6	1.387 (6)
Mo2—O8ⁱ	2.338 (2)	C1—H1	0.92 (5)
Mo3—O3	1.699 (3)	C2—H2	0.91 (5)
Mo3—O1	1.718 (3)	C3—C7	1.388 (5)
Mo3—O4	1.912 (2)	C3—C9	1.396 (5)
Mo3—O6	1.927 (2)	C3—C6	1.487 (5)
Mo3—O2	2.299 (3)	C4—C5	1.366 (6)
Mo3—O8ⁱ	2.450 (2)	C4—H4	0.88 (4)
Mo4—O12	1.696 (3)	C5—C6	1.396 (5)
Mo4—O2	1.750 (2)	C5—H5	0.86 (4)
Mo4—O13	1.954 (2)	C7—C8	1.381 (6)
Mo4—O10	1.957 (2)	C7—H7	0.96 (4)
Mo4—O8	2.155 (2)	C8—H8	1.02 (6)
Mo4—O8ⁱ	2.396 (2)	C9—C10	1.365 (6)
O4—Mo1ⁱ	1.898 (2)	C9—H9	0.89 (4)
O8—Mo2ⁱ	2.338 (2)	C10—H10	0.98 (5)
O8—Mo4ⁱ	2.396 (2)

O9—Mo1—O5	104.8 (1)	O10—Mo4—O8ⁱ	78.0 (1)
O9—Mo1—O4ⁱ	103.0 (1)	O8—Mo4—O8ⁱ	76.5 (1)
O5—Mo1—O4ⁱ	101.7 (1)	Mo4—O2—Mo3	118.1 (1)
O9—Mo1—O13	96.6 (1)	Mo1ⁱ—O4—Mo3	118.6 (1)
O5—Mo1—O13	100.4 (1)	Mo2—O6—Mo3	117.8 (1)
O4ⁱ—Mo1—O13	145.5 (1)	Mo4—O8—Mo2ⁱ	91.9 (1)
O9—Mo1—O8	95.9 (1)	Mo4—O8—Mo1	91.7 (1)
O5—Mo1—O8	159.0 (1)	Mo2ⁱ—O8—Mo1	164.5 (1)
O4ⁱ—Mo1—O8	76.7 (1)	Mo4—O8—Mo4ⁱ	103.5 (1)
O13—Mo1—O8	73.1 (1)	Mo2ⁱ—O8—Mo4ⁱ	96.0 (1)
O9—Mo1—O10ⁱ	163.7 (1)	Mo1—O8—Mo4ⁱ	97.8 (1)
O5—Mo1—O10ⁱ	87.6 (1)	Mo4—O8—Mo3ⁱ	164.5 (1)
O4ⁱ—Mo1—O10ⁱ	84.4 (1)	Mo2ⁱ—O8—Mo3ⁱ	86.3 (1)
O13—Mo1—O10ⁱ	70.4 (1)	Mo1—O8—Mo3ⁱ	86.3 (1)
O8—Mo1—O10ⁱ	71.4 (1)	Mo4ⁱ—O8—Mo3ⁱ	91.9 (1)
O11—Mo2—O7	104.8 (1)	Mo4—O10—Mo2ⁱ	110.0 (1)
O11—Mo2—O6	100.4 (1)	Mo4—O10—Mo1ⁱ	110.1 (1)
O7—Mo2—O6	100.6 (1)	Mo2ⁱ—O10—Mo1ⁱ	102.4 (1)
O11—Mo2—O10ⁱ	102.2 (1)	Mo4—O13—Mo1	109.1 (1)
O7—Mo2—O10ⁱ	96.6 (1)	Mo4—O13—Mo2	111.5 (1)
O6—Mo2—O10ⁱ	147.0 (1)	Mo1—O13—Mo2	105.0 (1)
O11—Mo2—O13	88.4 (1)	C4—N1—C2	122.2 (4)
O7—Mo2—O13	164.7 (1)	C4—N1—H1A	121 (3)
O6—Mo2—O13	84.1 (1)	C2—N1—H1A	116 (3)
O10ⁱ—Mo2—O13	72.8 (1)	C8—N2—C10	122.8 (4)
O11—Mo2—O8ⁱ	160.9 (1)	C8—N2—H2A	118 (3)
O7—Mo2—O8ⁱ	94.3 (1)	C10—N2—H2A	119 (3)
O6—Mo2—O8ⁱ	77.0 (1)	C2—C1—C6	119.8 (4)
O10ⁱ—Mo2—O8ⁱ	73.8 (1)	C2—C1—H1	118 (3)
O13—Mo2—O8ⁱ	72.5 (1)	C6—C1—H1	122 (3)
O3—Mo3—O1	104.6 (1)	N1—C2—C1	119.9 (4)
O3—Mo3—O4	100.2 (1)	N1—C2—H2	119 (3)
O1—Mo3—O4	100.8 (1)	C1—C2—H2	120 (3)
O3—Mo3—O6	97.4 (1)	C7—C3—C9	118.3 (3)
O1—Mo3—O6	104.2 (1)	C7—C3—C6	120.9 (3)
O4—Mo3—O6	144.5 (1)	C9—C3—C6	120.8 (3)
O3—Mo3—O2	166.4 (1)	N1—C4—C5	120.4 (4)
O1—Mo3—O2	89.0 (1)	N1—C4—H4	116 (3)
O4—Mo3—O2	78.4 (1)	C5—C4—H4	124 (3)
O6—Mo3—O2	77.3 (1)	C4—C5—C6	119.7 (4)
O3—Mo3—O8ⁱ	96.8 (1)	C4—C5—H5	119 (3)
O1—Mo3—O8ⁱ	158.6 (1)	C6—C5—H5	122 (3)
O4—Mo3—O8ⁱ	73.8 (1)	C1—C6—C5	117.9 (3)
O6—Mo3—O8ⁱ	73.8 (1)	C1—C6—C3	121.5 (3)
O2—Mo3—O8ⁱ	69.7 (1)	C5—C6—C3	120.6 (3)
O12—Mo4—O2	104.4 (1)	C8—C7—C3	120.0 (4)
O12—Mo4—O13	101.3 (1)	C8—C7—H7	117 (3)
O2—Mo4—O13	97.1 (1)	C3—C7—H7	123 (3)
O12—Mo4—O10	101.8 (1)	N2—C8—C7	119.3 (4)
O2—Mo4—O10	96.0 (1)	N2—C8—H8	112 (3)
O13—Mo4—O10	149.6 (1)	C7—C8—H8	128 (3)
O12—Mo4—O8	98.9 (1)	C10—C9—C3	119.7 (4)
O2—Mo4—O8	156.7 (1)	C10—C9—H9	120 (3)
O13—Mo4—O8	78.5 (1)	C3—C9—H9	120 (3)
O10—Mo4—O8	78.7 (1)	N2—C10—C9	119.9 (4)
O12—Mo4—O8ⁱ	175.4 (1)	N2—C10—H10	117 (3)
O2—Mo4—O8ⁱ	80.2 (1)	C9—C10—H10	123 (3)
O13—Mo4—O8ⁱ	77.5 (1)

Symmetry code: (i) −x+1, −y, −z+1.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1A···O1	0.93 (4)	1.79 (5)	2.722 (4)	174 (4)
N2—H2A···O7ⁱⁱ	0.88 (5)	1.91 (5)	2.755 (4)	161 (5)

Symmetry code: (ii) −x+5/2, y+1/2, −z+1/2.

Experimental details

Crystal data
Chemical formula	(C₁₀H₁₀N₂)[Mo₈O₂₆]
M_r	1499.92
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	293
a, b, c (Å)	10.7493 (2), 15.2255 (1), 10.7828 (2)
β (°)	93.840 (1)
V (Å³)	1760.79 (5)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	2.86
Crystal size (mm)	0.39 × 0.32 × 0.28

Data collection
Diffractometer	SMART CCD diffractometer
Absorption correction	Empirical (using intensity measurements) (SADABS; Sheldrick, 1996)
T_min, T_max	0.329, 0.449
No. of measured, independent and observed [I > 2σ(I)] reflections	6344, 3065, 2781
R_int	0.017
(sin θ/λ)_max (Å⁻¹)	0.594

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.022, 0.054, 1.09
No. of reflections	3065
No. of parameters	303
H-atom treatment	All H-atom parameters refined
Δρ_max, Δρ_min (e Å⁻³)	0.46, −0.67

Computer programs: SMART (Siemens, 1996), SMART and SAINT (Siemens, 1994), SMART and SAINT, SHELXS97 (Sheldrick, 1997), SHELXL97 (Sheldrick, 1997), SHELXL97.

Selected geometric parameters (Å, º) top

Mo1—O9	1.700 (3)	Mo3—O3	1.699 (3)
Mo1—O5	1.705 (3)	Mo3—O1	1.718 (3)
Mo1—O4ⁱ	1.898 (2)	Mo3—O4	1.912 (2)
Mo1—O13	2.009 (2)	Mo3—O6	1.927 (2)
Mo1—O8	2.341 (2)	Mo3—O2	2.299 (3)
Mo1—O10ⁱ	2.388 (2)	Mo3—O8ⁱ	2.450 (2)
Mo2—O11	1.707 (2)	Mo4—O12	1.696 (3)
Mo2—O7	1.720 (3)	Mo4—O2	1.750 (2)
Mo2—O6	1.898 (2)	Mo4—O13	1.954 (2)
Mo2—O10ⁱ	1.987 (2)	Mo4—O10	1.957 (2)
Mo2—O13	2.297 (2)	Mo4—O8	2.155 (2)
Mo2—O8ⁱ	2.338 (2)	Mo4—O8ⁱ	2.396 (2)

O9—Mo1—O5	104.8 (1)	O4—Mo3—O8ⁱ	73.8 (1)
O9—Mo1—O4ⁱ	103.0 (1)	O6—Mo3—O8ⁱ	73.8 (1)
O5—Mo1—O4ⁱ	101.7 (1)	O2—Mo3—O8ⁱ	69.7 (1)
O9—Mo1—O13	96.6 (1)	O12—Mo4—O2	104.4 (1)
O5—Mo1—O13	100.4 (1)	O12—Mo4—O13	101.3 (1)
O9—Mo1—O8	95.9 (1)	O2—Mo4—O13	97.1 (1)
O4ⁱ—Mo1—O8	76.7 (1)	O12—Mo4—O10	101.8 (1)
O13—Mo1—O8	73.1 (1)	O2—Mo4—O10	96.0 (1)
O5—Mo1—O10ⁱ	87.6 (1)	O12—Mo4—O8	98.9 (1)
O4ⁱ—Mo1—O10ⁱ	84.4 (1)	O13—Mo4—O8	78.5 (1)
O13—Mo1—O10ⁱ	70.4 (1)	O10—Mo4—O8	78.7 (1)
O8—Mo1—O10ⁱ	71.4 (1)	O2—Mo4—O8ⁱ	80.2 (1)
O11—Mo2—O7	104.8 (1)	O13—Mo4—O8ⁱ	77.5 (1)
O11—Mo2—O6	100.4 (1)	O10—Mo4—O8ⁱ	78.0 (1)
O7—Mo2—O6	100.6 (1)	O8—Mo4—O8ⁱ	76.5 (1)
O11—Mo2—O10ⁱ	102.2 (1)	Mo4—O2—Mo3	118.1 (1)
O7—Mo2—O10ⁱ	96.6 (1)	Mo1ⁱ—O4—Mo3	118.6 (1)
O11—Mo2—O13	88.4 (1)	Mo2—O6—Mo3	117.8 (1)
O6—Mo2—O13	84.1 (1)	Mo4—O8—Mo2ⁱ	91.9 (1)
O10ⁱ—Mo2—O13	72.8 (1)	Mo4—O8—Mo1	91.7 (1)
O7—Mo2—O8ⁱ	94.3 (1)	Mo4—O8—Mo4ⁱ	103.5 (1)
O6—Mo2—O8ⁱ	77.0 (1)	Mo2ⁱ—O8—Mo4ⁱ	96.0 (1)
O10ⁱ—Mo2—O8ⁱ	73.8 (1)	Mo1—O8—Mo4ⁱ	97.8 (1)
O13—Mo2—O8ⁱ	72.5 (1)	Mo2ⁱ—O8—Mo3ⁱ	86.3 (1)
O3—Mo3—O1	104.6 (1)	Mo1—O8—Mo3ⁱ	86.3 (1)
O3—Mo3—O4	100.2 (1)	Mo4ⁱ—O8—Mo3ⁱ	91.9 (1)
O1—Mo3—O4	100.8 (1)	Mo4—O10—Mo2ⁱ	110.0 (1)
O3—Mo3—O6	97.4 (1)	Mo4—O10—Mo1ⁱ	110.1 (1)
O1—Mo3—O6	104.2 (1)	Mo2ⁱ—O10—Mo1ⁱ	102.4 (1)
O1—Mo3—O2	89.0 (1)	Mo4—O13—Mo1	109.1 (1)
O4—Mo3—O2	78.4 (1)	Mo4—O13—Mo2	111.5 (1)
O6—Mo3—O2	77.3 (1)	Mo1—O13—Mo2	105.0 (1)
O3—Mo3—O8ⁱ	96.8 (1)