Hexaaqua­dodeca-μ-chloro-hexa­niobium(II,III) dichloride 2,2′-bipyridine tris­olvate

The title compound, [Nb₆Cl₁₂(H₂O)₆]Cl₂·3C₁₀H₈N₂, is an example of a `hybrid' inorganic–organic compound, where the inorganic and organic parts do not inter­act by covalent bonds but are joined by hydrogen bonding. The inorganic part contains a hexa­nuclear mixed-valence niobium cluster aqua cation [Nb₆(μ-Cl)₁₂(H₂O)₆]²⁺, with the typical {M₆X₁₂} structure, and two Cl⁻ counter-ions. The organic part consists of two crystallographically independent 2,2′-bipyridine mol­ecules; one is planar and lies on a centre of symmetry, and the other is twisted by 42.1 (5)°. The Nb—Nb, Nb—Cl and Nb—O bond distances are close to those found in other salts of this cation. The inorganic and organic parts are joined together by an extended system of hydrogen bonds. Six of the 12 H atoms of the aqua ligands form hydrogen bonds with the N atoms of the bipyridine mol­ecules, and the other six with Cl⁻ anions. At the same time, the bipyridine mol­ecules use both N atoms in hydrogen bonding with two cluster cations. Each Cl⁻ anion forms three Cl...H—O bonds with the three cluster cations. The resulting three-dimensional framework shows a non-trivial example of a (12,3,2,2) connected net. The disposition and relative orientation of the cluster cations and the geometric requirements of the hydrogen-bonds dictate the conformations of the bipyridine mol­ecules.

Key indicators

• Single-crystal X-ray study
• T = 292 K
• Mean [sigma](C-C) = 0.009 Å
• R factor = 0.037
• wR factor = 0.094
• Data-to-parameter ratio = 19.0

checkCIF/PLATON results

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Alert level C
PLAT042_ALERT_1_C Calc. and Rep. MoietyFormula Strings Differ ....          ?
PLAT250_ALERT_2_C Large U3/U1 Ratio for Average U(i,j) Tensor ....       2.48
PLAT342_ALERT_3_C Low Bond Precision on C-C bonds (x 1000) Ang ...          9
PLAT764_ALERT_4_C Overcomplete CIF Bond List Detected (Rep/Expd) .       1.15 Ratio

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   4 ALERT level C = Check and explain
   0 ALERT level G = General alerts; check

   1 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   1 ALERT type 2 Indicator that the structure model may be wrong or deficient
   1 ALERT type 3 Indicator that the structure quality may be low
   1 ALERT type 4 Improvement, methodology, query or suggestion

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S1. Comment

The chemistry of niobium clusters has developed rapidly in recent years (Brnicevic, Kojic-Prodic et al., 1995; Brnicevic, Planinic et al., 1995; Brnicevic, 1999; Perrin, 1999; Prokopuk & Shriver, 1999). Facile procedures for the preparation of substituted moieties with an Nb₆Cl₁₂ cluster core enable new compounds with various apical ligands to be obtained.

The title compound, (I), is an example of a `hybrid' inorganic–organic compound, where the inorganic and organic parts do not interact by covalent bonds but are joined by hydrogen bonds. The inorganic part contains a hexanuclear mixed-valence niobium cluster aqua cation, [Nb₆(µ-Cl)₁₂(H₂O)₆]²⁺ (Fig. 1), and two Cl⁻ counterions. The organic part consists of two crystallographically independent 2,2'-bipyridine molecules (Fig. 2).

The cluster core in the cation has the typical {M₆X₁₂} structure of an octahedron of metal atoms with halogen bridges on each edge. In addition, there are six coordinated terminal water molecules, one per Nb atom. The whole cation lies at the centre of symmetry (Wyckoff position 1a). The Nb—Nb, Nb—Cl and Nb—O bond distances (Table 1) are quite close to those found in other salts of this cation, namely [Nb₆Cl₁₂(H₂O)₆](CH₃O)₂·8H₂O (Brnicevic, Planinic et al., 1995) and [Nb₆Cl₁₂(H₂O)₆](CH₃O)₂·0.25CH₃OH·6H₂O (Brnicevic, Kojic-Prodic et al., 1995).

The two crystallographically independent 2,2'-bipyridine molecules possess different conformations: one of them is planar and located on the inversion centre, while the other is twisted by 42.1 (5)° and lies in a general position. The reason for this difference can be found in an analysis of the hydrogen bonding in the crystal, where all possible hydrogen bonds are realised (Table 2). Six of the 12 H atoms of the H₂O ligands form hydrogen bonds with the N atoms of the bipyridine molecules and the remaining six with Cl⁻ anions. At the same time, the bipyridine molecules use both N atoms in hydrogen bonds with two cluster cations. Each Cl⁻ anion forms three Cl···H—O hydrogen bonds with three cluster cations.

In the crystal packing one can select `inorganic' layers of clusters and Cl⁻ anions joined together by hydrogen bonds (Fig. 3). These layers lie in the (001) plane. The bipyridine molecules join the layers by means of N···H—O hydrogen bonds (Fig. 4). The centrosymmetric planar bipyridine molecule joins clusters in the (0,1,0) and (0,0,1) positions, with a cluster–cluster distance of 14.304 Å. The twisted molecule joins clusters in the (0,0,0) and (0,0,1) positions with a shorter cluster–cluster distance of 12.258 Å. This difference between the cluster–cluster distances results from the fact that the centre of the planar bipyridine molecule lies exactly on the line between the centres of the cations, while the centre of the twisted molecule is located away from this line (centre–centre–centre angle is 114.8°). Taking into account the rigid geometry of the cluster cation, one can state that the positions of the cations and their relative orientations, along with the hydrogen-bonding geometry, dictate the conformation of the bipyridine molecules.

The resulting three-dimensional framework shows a non-trivial example of a (12,3,2,2) connected net (O'Keeffe et al., 2000). According to the results of the ADS subprogram of the TOPOS4.0 program set (Blatov et al., 2000) the topology of the hydrogen-bond net can be characterized by the total Schläfli symbol of {4³}2{4⁸;6²²;8³¹;10⁵}{4}2{6}.

S2. Experimental

An aqueous solution (10 ml) of K₄Nb₆Cl₁₈ (50 mg, 0.037 mmol) was mixed with a solution of bpy (34.7 mg, 0.222 mmol) in ethanol (3 ml). The mixture was boiled for 30 min, and then left at room temperature. After one week, a dark-green solid, (I), was obtained. This was decanted, washed with ethanol and dried in air (yield 18.7 mg, 31.0%).

S3. Refinement

C-bound H atoms were positioned geometrically and refined as riding, with C—H = 0.93 Å and U_iso(H) = 1.2U_eq(C). The H atoms of the coordinated water molecules were located in a difference electron-density map and refined with U_iso(H) fixed at 0.05 Å⁻² and O—H bonds restrained to 0.82 (2) Å. The highest residual peak of 1.27 e Å⁻³ is situated 0.51 Å from atom Cl7.

Computing details

Data collection: APEX2 (Bruker, 2005); cell refinement: APEX2; data reduction: APEX2; program(s) used to solve structure: SHELXTL (Bruker, 2005); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: local programs.

Figures

	Fig. 1. The cluster cation in the crystal structure of (I). Displacement ellipsoids are drawn at the 50% probability level. Unlabelled atoms are related to labelled atoms by the symmetry operation (−x, −y, −z).
	Fig. 2. The organic molecules in the crystal structure of (I). Displacement ellipsoids are drawn at the 50% probability level. Unlabelled atoms are related to labelled atoms by the symmetry operation (−x, 1 − y, 1 − z).
	Fig. 3. The crystal packing of (I), showing the inorganic layers without the bipyridine molecules. Hydrogen bonds are shown by dashed lines. The H atoms of the bipyridine molecules have been omitted for clarity. [Please revise to show the atoms in the key at the same relative sizes as those in the diagram]
	Fig. 4. The crystal packing of (I), showing the inorganic layers joined by bipyridine molecules. Hydrogen bonds are shown by dashed lines. The H atoms of the bipyridine molecules have omitted for clarity. [Please revise to show the atoms in the key at the same relative sizes as those in the diagram]

Hexaaquadodeca-µ-chloro-hexaniobium(II,III) dichloride 2,2'-bipyridine trisolvate

Crystal data

[Nb6Cl12(H2O)6]Cl2·3C10H8N2	Z = 1
Mr = 1630.41	F(000) = 790
Triclinic, P1	Dx = 2.163 Mg m^−3
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 10.1546 (12) Å	Cell parameters from 3551 reflections
b = 11.2503 (15) Å	θ = 2.5–28.2°
c = 12.2583 (11) Å	µ = 2.12 mm^−1
α = 74.822 (4)°	T = 292 K
β = 74.551 (4)°	Prism, dark green
γ = 70.901 (4)°	0.09 × 0.03 × 0.01 mm
V = 1251.8 (3) Å^3

Data collection

Bruker X8 APEX CCD area-detector diffractometer	5658 independent reflections
Radiation source: fine-focus sealed tube	4317 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.033
Detector resolution: 25 pixels mm^-1	θmax = 27.5°, θmin = 1.8°
ω and ϕ scans	h = −13→13
Absorption correction: empirical (using intensity measurements) (SADABS; Bruker, 2005)	k = −14→14
Tmin = 0.871, Tmax = 0.980	l = −11→15
12802 measured reflections

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.037	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.094	H atoms treated by a mixture of independent and constrained refinement
S = 1.02	w = 1/[σ^2(Fo^2) + (0.0401P)^2 + 1.4105P] where P = (Fo^2 + 2Fc^2)/3
5658 reflections	(Δ/σ)max < 0.001
298 parameters	Δρmax = 1.27 e Å^−3
6 restraints	Δρmin = −0.67 e Å^−3

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. 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 (Ų)

	x	y	z	Uiso*/Ueq
Nb1	0.05951 (4)	0.05788 (4)	−0.17540 (3)	0.01997 (11)
Nb2	−0.12641 (4)	−0.09688 (4)	−0.02789 (3)	0.02059 (11)
Nb3	−0.16910 (4)	0.16257 (4)	0.00454 (3)	0.02023 (11)
Cl1	−0.07844 (13)	−0.04608 (12)	−0.24031 (9)	0.0284 (3)
Cl2	0.21978 (13)	0.18172 (12)	−0.17345 (9)	0.0287 (3)
Cl3	−0.13104 (13)	0.25848 (12)	−0.20287 (9)	0.0292 (3)
Cl4	−0.34951 (12)	0.07792 (12)	−0.02471 (10)	0.0281 (3)
Cl5	0.26992 (13)	−0.12353 (12)	−0.21349 (9)	0.0291 (3)
Cl6	0.05053 (13)	−0.30764 (11)	−0.03363 (10)	0.0296 (3)
Cl7	0.60972 (12)	0.58291 (11)	0.10687 (10)	0.0271 (3)
O1	0.1228 (4)	0.1230 (4)	−0.3636 (3)	0.0325 (9)
H11	0.166 (6)	0.073 (4)	−0.405 (4)	0.050*
H12	0.081 (6)	0.193 (3)	−0.398 (4)	0.050*
O2	−0.2633 (4)	−0.1996 (4)	−0.0585 (3)	0.0365 (9)
H21	−0.293 (6)	−0.256 (4)	−0.007 (4)	0.050*
H22	−0.273 (6)	−0.199 (6)	−0.124 (3)	0.050*
O3	−0.3507 (4)	0.3380 (4)	0.0101 (3)	0.0358 (9)
H31	−0.419 (4)	0.352 (6)	−0.020 (5)	0.050*
H32	−0.366 (6)	0.409 (3)	0.025 (5)	0.050*
C1	0.0201 (6)	0.5308 (5)	0.5375 (4)	0.0294 (11)
C2	0.0892 (7)	0.4576 (5)	0.6265 (5)	0.0450 (15)
H2A	0.1125	0.3686	0.6391	0.054*
C3	0.1234 (7)	0.5165 (6)	0.6966 (5)	0.0495 (17)
H3A	0.1711	0.4683	0.7557	0.059*
C4	0.0850 (7)	0.6487 (6)	0.6768 (4)	0.0459 (16)
H4A	0.1032	0.6918	0.7239	0.055*
C5	0.0192 (6)	0.7150 (5)	0.5852 (4)	0.0372 (13)
H5A	−0.0041	0.8041	0.5707	0.045*
C6	0.6446 (5)	0.8338 (5)	0.6499 (4)	0.0314 (12)
C7	0.6180 (6)	0.7851 (6)	0.5686 (5)	0.0410 (14)
H7A	0.5992	0.8370	0.4986	0.049*
C8	0.6200 (7)	0.6566 (6)	0.5932 (5)	0.0501 (16)
H8A	0.6014	0.6214	0.5401	0.060*
C9	0.6496 (7)	0.5826 (6)	0.6966 (5)	0.0496 (16)
H9A	0.6525	0.4963	0.7145	0.059*
C10	0.6748 (7)	0.6381 (7)	0.7730 (5)	0.0541 (17)
H10A	0.6950	0.5872	0.8429	0.065*
C11	0.6425 (5)	0.9693 (5)	0.6300 (4)	0.0314 (12)
C12	0.5788 (6)	1.0426 (5)	0.7150 (4)	0.0346 (12)
H12A	0.5339	1.0073	0.7871	0.041*
C13	0.5828 (6)	1.1682 (6)	0.6915 (5)	0.0432 (15)
H13A	0.5403	1.2185	0.7476	0.052*
C14	0.6501 (7)	1.2188 (6)	0.5847 (5)	0.0443 (15)
H14A	0.6558	1.3028	0.5673	0.053*
C15	0.7089 (7)	1.1402 (6)	0.5040 (5)	0.0437 (15)
H15A	0.7531	1.1746	0.4313	0.052*
N1	0.7066 (5)	1.0187 (4)	0.5234 (3)	0.0359 (11)
N2	0.6722 (5)	0.7617 (5)	0.7525 (4)	0.0414 (12)
N3	−0.0133 (5)	0.6592 (4)	0.5160 (3)	0.0311 (10)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Nb1	0.0216 (2)	0.0203 (2)	0.01567 (19)	−0.00330 (17)	−0.00408 (15)	−0.00234 (16)
Nb2	0.0217 (2)	0.0208 (2)	0.0192 (2)	−0.00501 (18)	−0.00606 (16)	−0.00265 (16)
Nb3	0.0207 (2)	0.0193 (2)	0.0183 (2)	−0.00151 (17)	−0.00530 (16)	−0.00344 (16)
Cl1	0.0334 (7)	0.0329 (7)	0.0213 (5)	−0.0087 (6)	−0.0094 (5)	−0.0056 (5)
Cl2	0.0303 (6)	0.0316 (7)	0.0239 (5)	−0.0135 (5)	−0.0042 (5)	0.0004 (5)
Cl3	0.0327 (7)	0.0246 (6)	0.0221 (5)	0.0001 (5)	−0.0073 (5)	0.0010 (5)
Cl4	0.0217 (6)	0.0306 (7)	0.0318 (6)	−0.0036 (5)	−0.0092 (5)	−0.0061 (5)
Cl5	0.0276 (6)	0.0309 (7)	0.0210 (5)	0.0003 (5)	−0.0015 (5)	−0.0060 (5)
Cl6	0.0329 (7)	0.0225 (6)	0.0343 (6)	−0.0033 (5)	−0.0112 (5)	−0.0079 (5)
Cl7	0.0272 (6)	0.0224 (6)	0.0354 (6)	−0.0065 (5)	−0.0115 (5)	−0.0072 (5)
O1	0.042 (2)	0.029 (2)	0.0191 (17)	−0.0037 (18)	−0.0038 (15)	−0.0014 (15)
O2	0.046 (2)	0.039 (2)	0.033 (2)	−0.0216 (19)	−0.0153 (19)	−0.0011 (18)
O3	0.032 (2)	0.028 (2)	0.046 (2)	0.0059 (18)	−0.0176 (17)	−0.0123 (18)
C1	0.037 (3)	0.028 (3)	0.023 (2)	−0.010 (2)	−0.006 (2)	−0.001 (2)
C2	0.078 (5)	0.027 (3)	0.041 (3)	−0.017 (3)	−0.033 (3)	0.002 (2)
C3	0.079 (5)	0.036 (4)	0.043 (3)	−0.019 (3)	−0.042 (3)	0.009 (3)
C4	0.076 (5)	0.041 (4)	0.032 (3)	−0.021 (3)	−0.024 (3)	−0.007 (3)
C5	0.053 (4)	0.026 (3)	0.035 (3)	−0.008 (3)	−0.015 (3)	−0.006 (2)
C6	0.027 (3)	0.040 (3)	0.025 (2)	−0.008 (2)	−0.002 (2)	−0.007 (2)
C7	0.037 (3)	0.050 (4)	0.038 (3)	−0.017 (3)	−0.008 (2)	−0.004 (3)
C8	0.051 (4)	0.053 (4)	0.051 (4)	−0.016 (3)	−0.012 (3)	−0.014 (3)
C9	0.057 (4)	0.033 (3)	0.059 (4)	−0.016 (3)	−0.017 (3)	0.000 (3)
C10	0.067 (5)	0.054 (4)	0.039 (3)	−0.021 (4)	−0.013 (3)	0.003 (3)
C11	0.027 (3)	0.035 (3)	0.027 (2)	−0.002 (2)	−0.007 (2)	−0.003 (2)
C12	0.034 (3)	0.040 (3)	0.029 (3)	−0.006 (3)	−0.008 (2)	−0.009 (2)
C13	0.039 (3)	0.048 (4)	0.045 (3)	0.002 (3)	−0.015 (3)	−0.024 (3)
C14	0.064 (4)	0.035 (3)	0.039 (3)	−0.018 (3)	−0.013 (3)	−0.007 (3)
C15	0.056 (4)	0.046 (4)	0.031 (3)	−0.021 (3)	−0.005 (3)	−0.005 (3)
N1	0.043 (3)	0.036 (3)	0.029 (2)	−0.012 (2)	−0.006 (2)	−0.008 (2)
N2	0.048 (3)	0.043 (3)	0.032 (2)	−0.013 (2)	−0.013 (2)	0.001 (2)
N3	0.040 (3)	0.028 (2)	0.028 (2)	−0.010 (2)	−0.0113 (19)	−0.0035 (18)

Geometric parameters (Å, º)

Nb1—Nb2^i	2.9213 (6)	C1—C1^ii	1.486 (10)
Nb1—Nb2	2.9239 (6)	C1—C2	1.386 (7)
Nb1—Nb3	2.9128 (6)	C1—N3	1.341 (6)
Nb1—Nb3^i	2.9141 (6)	C2—H2A	0.9300
Nb1—Cl1	2.4731 (13)	C2—C3	1.380 (8)
Nb1—Cl2	2.4724 (13)	C3—H3A	0.9300
Nb1—Cl3	2.4581 (13)	C3—C4	1.380 (8)
Nb1—Cl5	2.4622 (12)	C4—H4A	0.9300
Nb1—O1	2.214 (3)	C4—C5	1.378 (7)
Nb2—Nb1^i	2.9213 (6)	C5—H5A	0.9300
Nb2—Nb3^i	2.9204 (7)	C5—N3	1.337 (6)
Nb2—Nb3	2.9246 (7)	C6—C7	1.375 (7)
Nb2—Cl1	2.4641 (12)	C6—C11	1.474 (7)
Nb2—Cl2^i	2.4522 (12)	C6—N2	1.350 (6)
Nb2—Cl4	2.4656 (13)	C7—H7A	0.9300
Nb2—Cl6	2.4673 (13)	C7—C8	1.392 (8)
Nb2—O2	2.228 (4)	C8—H8A	0.9300
Nb3—Nb1^i	2.9141 (6)	C8—C9	1.370 (8)
Nb3—Nb2^i	2.9204 (7)	C9—H9A	0.9300
Nb3—Cl3	2.4679 (12)	C9—C10	1.368 (9)
Nb3—Cl4	2.4621 (13)	C10—H10A	0.9300
Nb3—Cl5^i	2.4719 (11)	C10—N2	1.339 (8)
Nb3—Cl6^i	2.4619 (13)	C11—C12	1.388 (7)
Nb3—O3	2.219 (4)	C11—N1	1.358 (6)
Cl2—Nb2^i	2.4522 (12)	C12—H12A	0.9300
Cl5—Nb3^i	2.4719 (11)	C12—C13	1.379 (8)
Cl6—Nb3^i	2.4619 (13)	C13—H13A	0.9300
O1—H11	0.80 (4)	C13—C14	1.376 (8)
O1—H12	0.83 (4)	C14—H14A	0.9300
O2—H21	0.84 (5)	C14—C15	1.383 (8)
O2—H22	0.83 (4)	C15—H15A	0.9300
O3—H31	0.82 (5)	C15—N1	1.332 (7)
O3—H32	0.82 (4)
Nb2^i—Nb1—Nb2	90.354 (17)	Cl4—Nb3—Nb2	53.65 (3)
Nb3—Nb1—Nb2^i	60.075 (15)	Cl4—Nb3—Cl3	88.63 (4)
Nb3^i—Nb1—Nb2^i	60.157 (16)	Cl4—Nb3—Cl5^i	88.04 (4)
Nb3—Nb1—Nb2	60.141 (16)	Cl5^i—Nb3—Nb1	143.65 (3)
Nb3^i—Nb1—Nb2	60.031 (16)	Cl5^i—Nb3—Nb1^i	53.65 (3)
Nb3—Nb1—Nb3^i	89.996 (17)	Cl5^i—Nb3—Nb2^i	96.02 (3)
Cl1—Nb1—Nb2^i	143.90 (3)	Cl5^i—Nb3—Nb2	96.13 (3)
Cl1—Nb1—Nb2	53.54 (3)	Cl6^i—Nb3—Nb1	95.42 (3)
Cl1—Nb1—Nb3	96.25 (3)	Cl6^i—Nb3—Nb1^i	97.23 (3)
Cl1—Nb1—Nb3^i	96.02 (3)	Cl6^i—Nb3—Nb2^i	53.75 (3)
Cl2—Nb1—Nb2^i	53.30 (3)	Cl6^i—Nb3—Nb2	144.08 (3)
Cl2—Nb1—Nb2	143.65 (3)	Cl6^i—Nb3—Cl3	88.24 (4)
Cl2—Nb1—Nb3	96.07 (3)	Cl6^i—Nb3—Cl4	162.25 (4)
Cl2—Nb1—Nb3^i	95.92 (3)	Cl6^i—Nb3—Cl5^i	89.79 (4)
Cl2—Nb1—Cl1	162.81 (4)	O3—Nb3—Nb1	135.15 (10)
Cl3—Nb1—Nb2^i	96.81 (3)	O3—Nb3—Nb1^i	134.84 (10)
Cl3—Nb1—Nb2	95.73 (3)	O3—Nb3—Nb2^i	134.47 (11)
Cl3—Nb1—Nb3	53.91 (3)	O3—Nb3—Nb2	135.17 (11)
Cl3—Nb1—Nb3^i	143.89 (3)	O3—Nb3—Cl3	81.57 (10)
Cl3—Nb1—Cl1	87.99 (4)	O3—Nb3—Cl4	81.53 (11)
Cl3—Nb1—Cl2	89.62 (5)	O3—Nb3—Cl5^i	81.20 (10)
Cl3—Nb1—Cl5	162.12 (4)	O3—Nb3—Cl6^i	80.73 (11)
Cl5—Nb1—Nb2^i	96.43 (3)	Nb2—Cl1—Nb1	72.63 (3)
Cl5—Nb1—Nb2	96.15 (3)	Nb2^i—Cl2—Nb1	72.77 (3)
Cl5—Nb1—Nb3	143.95 (3)	Nb1—Cl3—Nb3	72.50 (3)
Cl5—Nb1—Nb3^i	53.95 (3)	Nb3—Cl4—Nb2	72.81 (4)
Cl5—Nb1—Cl1	88.38 (4)	Nb1—Cl5—Nb3^i	72.40 (3)
Cl5—Nb1—Cl2	88.70 (5)	Nb3^i—Cl6—Nb2	72.66 (4)
O1—Nb1—Nb2^i	134.23 (11)	Nb1—O1—H11	121 (4)
O1—Nb1—Nb2	135.41 (11)	Nb1—O1—H12	122 (4)
O1—Nb1—Nb3	134.36 (10)	H11—O1—H12	113 (6)
O1—Nb1—Nb3^i	135.64 (10)	Nb2—O2—H21	122 (4)
O1—Nb1—Cl1	81.88 (11)	Nb2—O2—H22	123 (4)
O1—Nb1—Cl2	80.94 (11)	H21—O2—H22	113 (6)
O1—Nb1—Cl3	80.47 (10)	Nb3—O3—H31	123 (4)
O1—Nb1—Cl5	81.69 (10)	Nb3—O3—H32	136 (4)
Nb1^i—Nb2—Nb1	89.646 (17)	H31—O3—H32	100 (6)
Nb1^i—Nb2—Nb3	59.800 (14)	C2—C1—C1^ii	120.9 (6)
Nb1—Nb2—Nb3	59.742 (15)	N3—C1—C1^ii	117.6 (5)
Nb3^i—Nb2—Nb1^i	59.819 (14)	N3—C1—C2	121.5 (5)
Nb3^i—Nb2—Nb1	59.818 (15)	C1—C2—H2A	120.0
Nb3^i—Nb2—Nb3	89.642 (17)	C3—C2—C1	120.1 (5)
Cl1—Nb2—Nb1^i	143.47 (3)	C3—C2—H2A	120.0
Cl1—Nb2—Nb1	53.83 (3)	C2—C3—H3A	120.8
Cl1—Nb2—Nb3^i	96.07 (3)	C4—C3—C2	118.5 (5)
Cl1—Nb2—Nb3	96.15 (3)	C4—C3—H3A	120.8
Cl1—Nb2—Cl4	89.52 (4)	C3—C4—H4A	120.9
Cl1—Nb2—Cl6	89.89 (4)	C5—C4—C3	118.2 (5)
Cl2^i—Nb2—Nb1^i	53.94 (3)	C5—C4—H4A	120.9
Cl2^i—Nb2—Nb1	143.58 (3)	C4—C5—H5A	118.0
Cl2^i—Nb2—Nb3^i	96.33 (3)	N3—C5—C4	124.0 (5)
Cl2^i—Nb2—Nb3	96.11 (3)	N3—C5—H5A	118.0
Cl2^i—Nb2—Cl1	162.59 (5)	C7—C6—C11	121.4 (5)
Cl2^i—Nb2—Cl4	87.86 (4)	N2—C6—C7	122.5 (5)
Cl2^i—Nb2—Cl6	87.68 (4)	N2—C6—C11	116.1 (5)
Cl4—Nb2—Nb1^i	95.39 (3)	C6—C7—H7A	120.7
Cl4—Nb2—Nb1	96.38 (3)	C6—C7—C8	118.6 (5)
Cl4—Nb2—Nb3^i	143.17 (3)	C8—C7—H7A	120.7
Cl4—Nb2—Nb3	53.54 (3)	C7—C8—H8A	120.4
Cl4—Nb2—Cl6	163.14 (5)	C9—C8—C7	119.2 (6)
Cl6—Nb2—Nb1^i	95.09 (3)	C9—C8—H8A	120.4
Cl6—Nb2—Nb1	96.85 (3)	C8—C9—H9A	120.7
Cl6—Nb2—Nb3^i	53.58 (3)	C10—C9—C8	118.7 (6)
Cl6—Nb2—Nb3	143.20 (4)	C10—C9—H9A	120.7
O2—Nb2—Nb1^i	135.36 (9)	C9—C10—H10A	118.2
O2—Nb2—Nb1	134.99 (9)	N2—C10—C9	123.6 (6)
O2—Nb2—Nb3^i	135.54 (11)	N2—C10—H10A	118.2
O2—Nb2—Nb3	134.82 (11)	C12—C11—C6	122.1 (5)
O2—Nb2—Cl1	81.17 (10)	N1—C11—C6	116.1 (4)
O2—Nb2—Cl2^i	81.42 (10)	N1—C11—C12	121.8 (5)
O2—Nb2—Cl4	81.29 (11)	C11—C12—H12A	120.4
O2—Nb2—Cl6	81.97 (11)	C13—C12—C11	119.2 (5)
Nb1—Nb3—Nb1^i	90.004 (17)	C13—C12—H12A	120.4
Nb1—Nb3—Nb2^i	60.106 (15)	C12—C13—H13A	120.2
Nb1^i—Nb3—Nb2^i	60.151 (15)	C14—C13—C12	119.6 (5)
Nb1—Nb3—Nb2	60.117 (15)	C14—C13—H13A	120.2
Nb1^i—Nb3—Nb2	60.043 (16)	C13—C14—H14A	121.2
Nb2^i—Nb3—Nb2	90.358 (17)	C13—C14—C15	117.6 (6)
Cl3—Nb3—Nb1	53.59 (3)	C15—C14—H14A	121.2
Cl3—Nb3—Nb1^i	143.59 (3)	C14—C15—H15A	117.8
Cl3—Nb3—Nb2^i	96.61 (3)	N1—C15—C14	124.5 (5)
Cl3—Nb3—Nb2	95.50 (3)	N1—C15—H15A	117.8
Cl3—Nb3—Cl5^i	162.75 (4)	C15—N1—C11	117.3 (5)
Cl4—Nb3—Nb1	96.75 (3)	C10—N2—C6	117.4 (5)
Cl4—Nb3—Nb1^i	95.65 (3)	C5—N3—C1	117.8 (4)
Cl4—Nb3—Nb2^i	144.00 (3)
N3—C1—C1^ii—N3^ii	180.000 (1)	N1—C11—C6—N2	137.9 (5)

Symmetry codes: (i) −x, −y, −z; (ii) −x, −y+1, −z+1.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O1—H11···N1^iii	0.80 (4)	1.94 (5)	2.720 (5)	167 (6)
O1—H12···N3^iv	0.83 (4)	1.96 (2)	2.768 (5)	165 (6)
O2—H21···Cl7^v	0.84 (5)	2.31 (5)	3.136 (4)	170 (6)
O2—H22···N2^vi	0.83 (4)	1.93 (3)	2.740 (6)	162 (6)
O3—H31···Cl7^iv	0.82 (5)	2.27 (5)	3.095 (4)	172 (6)
O3—H32···Cl7^vii	0.82 (4)	2.34 (2)	3.145 (4)	167 (6)

Symmetry codes: (iii) −x+1, −y+1, −z; (iv) −x, −y+1, −z; (v) x−1, y−1, z; (vi) x−1, y−1, z−1; (vii) x−1, y, z.