Crystal structure of a heterometallic coordination polymer: poly[di­aqua­bis­(μ7-benzene-1,3,5-tri­carboxyl­ato)dicalcium(II)copper(II)]

Zhang, F.; Zhang, B.-G.

doi:10.1107/S205698901700665X

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Volume 73| Part 6| June 2017| Pages 835-837

https://doi.org/10.1107/S205698901700665X

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Crystal structure of a heterometallic coordination polymer: poly[diaquabis(μ₇-benzene-1,3,5-tricarboxylato)dicalcium(II)copper(II)]

Feng Zhang ^a ^* and Bing-Guang Zhang ^a

^aKey Laboratory of Catalysis and Materials Sciences of the State Ethnic Affairs Commission & Ministry of Education, College of Chemistry and Material Science, South-Central University for Nationalities, Wuhan 430074, People's Republic of China
^*Correspondence e-mail: zhangbg68@yahoo.com

Edited by D.-J. Xu, Zhejiang University (Yuquan Campus), China (Received 13 March 2017; accepted 3 May 2017; online 12 May 2017)

In the title complex, [Ca₂Cu(C₉H₃O₆)₂(H₂O)₂]_n, the Ca^II and Cu^II cations are bridged by the benzene-1,3,5-tricarboxylate anions (BTC³⁻) to form the coordination polymer, in which each BTC³⁻ anion bridges two Cu^II and five Ca^II cations with a μ₇ coordination mode. The Cu^II cation, located at an inversion centre, is in a nearly square-planar geometry defined by four O atoms from four bridging BTC³⁻ anions, while the Ca^II cation is in a distorted octahedral geometry defined by five O atoms from bridging BTC³⁻ anions and one water molecule. O—H⋯O hydrogen bonds between coordinating water molecules and carboxyl groups further stabilize the structure; π–π stacking is also observed between parallel benzene rings, the centroid-to-centroid distance being 3.357 (2) Å.

Keywords: crystal structure; heterometallic complex; copper carboxylates; calcium carboxylates; π–π stacking.

CCDC reference: 1547715

1. Chemical context

In recent years, the rational design and synthesis of heterometallic coordination compounds have attracted much attention due to their potential applications in magnetism, luminescence, adsorption, chemical sensing and catalysis, as well as their aesthetically beautiful architectures and topologies (Cui et al., 2012 ; Huang et al., 2013 ; Ma et al., 2014 ; Wimberg et al., 2012 ). However, hererometallic organic frameworks are investigated less frequently than single-metal organic frameworks in crystal engineering, mainly because of the competitive complexation of different metal ions in the self-assembly progress. Recently, alkaline-earth metal ions have attracted more and more research interest owing to their unpredictable coordination number and pH-dependent self-assembly in the construction of novel topological coordination compounds (Borah et al., 2011 ; Chen et al., 2011 ). However, the larger atomic radii and high enthalpy of hydration make it relatively difficult to design the coordination polymers of alkaline-earth metal ions as well as to synthesize them from aqueous solution (Reger et al., 2013 ). As alkaline-earth metals and transition metals coordinate to the same ligand, it often gives rise to homometallic coordination compounds rather than heterometallic ones. In this regard, one of the effective synthetic strategies in building the alkaline-earth-metal-containing compounds is to employ appropriate bridging ligands. As a multifunctional hybrid ligand, H₃BTC (benzene-1,3,5-tricarboxylic acid) in its partly or fully deprotonated form exhibits versatile coordination modes and can bind to the metal ions by making full use of the carboxylate oxygen atoms. In addition, heterometallic compounds incorporating only the H₃BTC ligand are few in number (Chen et al., 2004 ; Li et al., 2010 ; Sun et al., 2014 , 2016 ; Xu et al., 2014 ). As part of our ongoing studies on these compounds, we describe here synthesis and crystal structure of the title compound, [Ca₂Cu(BTC)₂(H₂O)₂]_n, (1).

2. Structural commentary

The asymmetric unit of (1) contains one copper(II) cation (located at an inversion centre), one calcium(II) cation, one BTC³⁻ anion and one coordinating water molecule (Fig. 1). The Cu—O bond lengths are in the range 1.9435 (19)–1.9800 (19) Å and the Ca—O bond lengths are in the range of 2.280 (2)–2.466 (2) Å (Table 1). All data are comparable to those reported for other related Cu^II–BTC and Ca^II–BTC complexes (Chui et al., 1999 ; Yang et al., 2004 ) . Each Cu^II cation is four-coordinated by four oxygen atoms from four different BTC³⁻ anions, forming a nearly square-planar geometry. Each Ca^II cation is six-coordinated by five carboxylate oxygen atoms from five different BTC³⁻ anions and one terminal water molecule, displaying a distorted octahedron (Fig. 1). The mean deviation of the equatorial plane constructed by atoms O1, O4, O6 and OW1 is 0.06 Å. The H₃BTC molecule is fully deprotonated and bridges two Cu^II ions and five Ca^II ions in a μ₇ coordination mode.

Table 1
Selected bond lengths (Å)

Ca1—O1	2.338 (2)	Ca1—O6^iv	2.357 (2)
Ca1—O3ⁱ	2.280 (2)	Ca1—OW1	2.390 (2)
Ca1—O4ⁱⁱ	2.333 (2)	Cu1—O2	1.9435 (19)
Ca1—O5ⁱⁱⁱ	2.466 (2)	Cu1—O5^v	1.9800 (19)
Symmetry codes: (i) x, y, z-1; (ii) -x, -y+1, -z+2; (iii) x, y+1, z; (iv) -x, -y+1, -z+1; (v) -x+1, -y+1, -z+2.

Figure 1
The coordination mode and atom-numbering scheme for (1). Displacement ellipsoids for non H-atoms are drawn at the 50% probability level, with H atoms shown as spheres of arbitrary radius. [Symmetry codes: (A) x, y, z + 1; (B) −x, −y + 1, −z + 2; (C) x, y − 1, z; (D) −x, −y + 1, −z + 1; (E) −x + 1, −y + 2, −z + 2; (F) x, y + 1, z; (G) −x + 1, −y + 1, −z + 2; (H) x, y, z − 1.]

3. Supramolecular features

Each CuO₄ quadrilateral shares a vertex (O5) with two CaO₆ polyhedra to form a trinuclear unit {CuCa₂O₁₄} with Ca–O–Cu–O–Ca connectivity (Fig. 2). Such units are cross-linked by the μ₇-BTC³⁻ anions to create a three-dimensional framework (Fig. 3). In addition, the terminal water molecule is hydrogen bonded to the carboxylate O atoms (Table 2), forming a two-dimensional network parallel to (100). π-π stacking interactions between (C1–C6) benzene rings [Cg⋯Cg(−x, 1 − y, 2 − z) = 3.357 (2) Å] further stabilize the crystal structure.

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
OW1—HW1A⋯O4^v	0.84 (1)	1.95 (1)	2.793 (3)	173 (3)
OW1—HW1B⋯O2^vi	0.84 (1)	2.31 (2)	3.020 (3)	143 (3)
Symmetry codes: (v) -x+1, -y+1, -z+2; (vi) -x+1, -y+2, -z+2.

Figure 2
The trinuclear unit constructed from a [CaO₆] octahedron and a [CuO₄] quadrilateral.

Figure 3
Polyhedral view of the three-dimensional heterometallic coordination framework of (1). All H atoms have been omitted for clarity.

4. Synthesis and crystallization

The title compound was synthesized using a similar procedure to that for the synthesis of the analogous compound [CuSr₂(BTC)₂]·10H₂O (Sun et al., 2016). A mixture of H₃BTC (210 mg, 1 mmol), CuCl₂·6H₂O (121 mg, 0.5 mmol) and CaCl₂ (110 mg, 1 mmol) in 15 mL of distilled water was stirred for 10 min in air; 0.5 M NaOH was then added dropwise, and then the mixture was turned into a Parr Teflon-lined stainless steel vessel and heated to 443 K for 3 d. Blue block-shaped crystals suitable for X-ray diffraction were obtained in 60% yield (based on benzene-1,3,5-tricarboxylic acid).

5. Refinement

Crystal data, data collection and structure refinement details are summarized in Table 3. The hydrogen atoms of the coordinating water molecule were located from a difference-Fourier map, but refined using a riding model with isotropic displacement parameters U_iso(H) = 1.2U_eq(O). Hydrogen atoms attached to carbon atoms were positioned geometrically (C—H = 0.93 Å) and refined with U_iso(H) = 1.2U_eq(C).

Table 3
Experimental details

Crystal data
Chemical formula	[Ca₂Cu(C₉H₃O₆)₂(H₂O)₂]
M_r	593.96
Crystal system, space group	Triclinic, P $[\overline{1}]$
Temperature (K)	296
a, b, c (Å)	6.664 (3), 8.754 (4), 8.925 (4)
α, β, γ (°)	103.065 (4), 110.140 (4), 92.776 (5)
V (Å³)	471.6 (4)
Z	1
Radiation type	Mo Kα
μ (mm⁻¹)	1.79
Crystal size (mm)	0.18 × 0.15 × 0.14

Data collection
Diffractometer	Bruker SMART CCD
Absorption correction	Multi-scan (SADABS; Bruker, 2009 )
T_min, T_max	0.721, 0.766
No. of measured, independent and observed [I > 2σ(I)] reflections	2442, 1635, 1588
R_int	0.012
(sin θ/λ)_max (Å⁻¹)	0.595

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.029, 0.084, 1.04
No. of reflections	1635
No. of parameters	166
No. of restraints	3
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.35, −0.68
Computer programs: APEX2 and SAINT (Bruker, 2009), SHELXS97 and SHELXTL (Sheldrick, 2008 ), SHELXL2014 (Sheldrick, 2015 ) and DIAMOND (Brandenburg, 2006 ).

Supporting information

CCDC reference: 1547715

Crystal structure: contains datablocks I, global. DOI: https://doi.org/10.1107/S205698901700665X/xu5901sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S205698901700665X/xu5901Isup2.hkl

checkCIF report

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015); molecular graphics: SHELXTL97 (Sheldrick, 2008) and DIAMOND (Brandenburg, 2006); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Poly[diaquabis(µ₇-benzene-1,3,5-tricarboxylato)dicalcium(II)copper(II)] top

Crystal data top

[Ca₂Cu(C₉H₃O₆)₂(H₂O)₂]	Z = 1
M_r = 593.96	F(000) = 299
Triclinic, P1	D_x = 2.091 Mg m⁻³
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 6.664 (3) Å	Cell parameters from 1990 reflections
b = 8.754 (4) Å	θ = 2.4–27.5°
c = 8.925 (4) Å	µ = 1.79 mm⁻¹
α = 103.065 (4)°	T = 296 K
β = 110.140 (4)°	Block, blue
γ = 92.776 (5)°	0.18 × 0.15 × 0.14 mm
V = 471.6 (4) Å³

Data collection top

Bruker SMART CCD diffractometer	1635 independent reflections
Radiation source: fine-focus sealed tube	1588 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.012
φ and ω scans	θ_max = 25.0°, θ_min = 2.4°
Absorption correction: multi-scan (SADABS; Bruker, 2009)	h = −7→7
T_min = 0.721, T_max = 0.766	k = −10→4
2442 measured reflections	l = −10→10

Refinement top

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)] = 0.029	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.084	H atoms treated by a mixture of independent and constrained refinement
S = 1.04	w = 1/[σ²(F_o²) + (0.0501P)² + 0.6456P] where P = (F_o² + 2F_c²)/3
1635 reflections	(Δ/σ)_max < 0.001
166 parameters	Δρ_max = 0.35 e Å⁻³
3 restraints	Δρ_min = −0.68 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. 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 > 2sigma(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
Ca1	0.13337 (8)	0.79200 (6)	0.58531 (6)	0.01430 (16)
Cu1	0.5000	1.0000	1.0000	0.01590 (16)
O1	0.2949 (3)	0.6981 (2)	0.8180 (2)	0.0206 (4)
O2	0.3877 (3)	0.8375 (2)	1.0782 (2)	0.0192 (4)
O3	0.2155 (4)	0.5598 (2)	1.4590 (2)	0.0273 (5)
O4	0.1993 (3)	0.2977 (2)	1.4102 (2)	0.0190 (4)
O5	0.2085 (3)	0.0033 (2)	0.8405 (2)	0.0186 (4)
O6	0.0233 (4)	0.1170 (2)	0.6527 (2)	0.0283 (5)
C1	0.2707 (4)	0.5610 (3)	1.0114 (3)	0.0126 (5)
C2	0.2808 (4)	0.5623 (3)	1.1690 (3)	0.0145 (5)
H2A	0.3166	0.6577	1.2499	0.017*
C3	0.2377 (4)	0.4211 (3)	1.2074 (3)	0.0136 (5)
C4	0.1929 (4)	0.2786 (3)	1.0883 (3)	0.0142 (5)
H4A	0.1703	0.1841	1.1148	0.017*
C5	0.1815 (4)	0.2765 (3)	0.9288 (3)	0.0142 (5)
C6	0.2163 (4)	0.4182 (3)	0.8895 (3)	0.0136 (5)
H6A	0.2034	0.4176	0.7822	0.016*
C7	0.3178 (4)	0.7085 (3)	0.9639 (3)	0.0139 (5)
C8	0.2195 (4)	0.4278 (3)	1.3728 (3)	0.0154 (5)
C9	0.1339 (4)	0.1255 (3)	0.7989 (3)	0.0142 (5)
OW1	0.4854 (3)	0.8960 (3)	0.6111 (3)	0.0315 (5)
HW1A	0.587 (4)	0.844 (3)	0.604 (4)	0.038*
HW1B	0.544 (5)	0.9871 (18)	0.669 (4)	0.038*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Ca1	0.0188 (3)	0.0142 (3)	0.0099 (3)	0.0011 (2)	0.0048 (2)	0.0040 (2)
Cu1	0.0204 (3)	0.0110 (2)	0.0147 (3)	0.00010 (17)	0.00383 (19)	0.00479 (18)
O1	0.0344 (11)	0.0158 (9)	0.0143 (9)	0.0058 (8)	0.0090 (8)	0.0084 (7)
O2	0.0282 (10)	0.0125 (9)	0.0145 (9)	−0.0024 (7)	0.0056 (8)	0.0035 (7)
O3	0.0480 (13)	0.0191 (10)	0.0181 (10)	0.0061 (9)	0.0181 (10)	0.0016 (8)
O4	0.0236 (10)	0.0189 (10)	0.0181 (9)	0.0014 (7)	0.0094 (8)	0.0092 (8)
O5	0.0228 (10)	0.0107 (9)	0.0180 (9)	0.0032 (7)	0.0027 (8)	0.0030 (7)
O6	0.0452 (13)	0.0206 (10)	0.0118 (10)	0.0027 (9)	0.0010 (9)	0.0051 (8)
C1	0.0118 (12)	0.0128 (12)	0.0131 (12)	0.0020 (9)	0.0033 (10)	0.0049 (10)
C2	0.0160 (12)	0.0128 (12)	0.0141 (12)	0.0015 (9)	0.0051 (10)	0.0032 (10)
C3	0.0148 (12)	0.0140 (12)	0.0124 (12)	0.0025 (9)	0.0049 (10)	0.0043 (10)
C4	0.0169 (12)	0.0119 (12)	0.0155 (12)	0.0035 (9)	0.0057 (10)	0.0065 (10)
C5	0.0143 (12)	0.0135 (12)	0.0131 (12)	0.0032 (10)	0.0030 (10)	0.0033 (10)
C6	0.0159 (12)	0.0130 (12)	0.0125 (12)	0.0044 (10)	0.0040 (10)	0.0057 (10)
C7	0.0145 (12)	0.0135 (12)	0.0167 (13)	0.0051 (9)	0.0063 (10)	0.0078 (10)
C8	0.0154 (12)	0.0174 (13)	0.0130 (12)	0.0024 (10)	0.0047 (10)	0.0036 (10)
C9	0.0177 (12)	0.0129 (12)	0.0129 (13)	0.0017 (10)	0.0056 (10)	0.0050 (10)
OW1	0.0262 (11)	0.0264 (11)	0.0459 (14)	0.0047 (9)	0.0166 (10)	0.0116 (10)

Geometric parameters (Å, º) top

Ca1—O1	2.338 (2)	O5—Ca1^viii	2.466 (2)
Ca1—O3ⁱ	2.280 (2)	O6—C9	1.241 (3)
Ca1—O4ⁱⁱ	2.333 (2)	O6—Ca1^iv	2.357 (2)
Ca1—O5ⁱⁱⁱ	2.466 (2)	O6—Ca1^viii	2.954 (2)
Ca1—O6^iv	2.357 (2)	C1—C2	1.382 (4)
Ca1—OW1	2.390 (2)	C1—C6	1.395 (4)
Ca1—Cu1	3.6439 (13)	C1—C7	1.499 (3)
Cu1—O2^v	1.9435 (19)	C2—C3	1.398 (4)
Cu1—O2	1.9435 (19)	C2—H2A	0.9300
Cu1—O5^vi	1.9800 (19)	C3—C4	1.386 (4)
Cu1—O5ⁱⁱⁱ	1.9800 (19)	C3—C8	1.511 (3)
Cu1—Ca1^v	3.6439 (13)	C4—C5	1.395 (4)
O1—C7	1.239 (3)	C4—H4A	0.9300
O2—C7	1.278 (3)	C5—C6	1.393 (4)
O3—C8	1.242 (3)	C5—C9	1.485 (3)
O3—Ca1^vii	2.280 (2)	C6—H6A	0.9300
O4—C8	1.271 (3)	C8—Ca1ⁱⁱ	3.141 (3)
O4—Ca1ⁱⁱ	2.333 (2)	C9—Ca1^viii	3.104 (3)
O5—C9	1.278 (3)	OW1—HW1A	0.844 (10)
O5—Cu1^viii	1.9800 (19)	OW1—HW1B	0.836 (10)

O3ⁱ—Ca1—O4ⁱⁱ	99.86 (8)	C7—O2—Cu1	110.48 (16)
O3ⁱ—Ca1—O1	81.17 (8)	C8—O3—Ca1^vii	168.1 (2)
O4ⁱⁱ—Ca1—O1	87.46 (7)	C8—O4—Ca1ⁱⁱ	118.28 (16)
O3ⁱ—Ca1—O6^iv	97.47 (8)	C9—O5—Cu1^viii	125.84 (16)
O4ⁱⁱ—Ca1—O6^iv	93.57 (8)	C9—O5—Ca1^viii	107.73 (15)
O1—Ca1—O6^iv	178.43 (7)	Cu1^viii—O5—Ca1^viii	109.61 (8)
O3ⁱ—Ca1—OW1	83.82 (8)	C9—O6—Ca1^iv	157.26 (18)
O4ⁱⁱ—Ca1—OW1	173.99 (8)	C9—O6—Ca1^viii	85.06 (15)
O1—Ca1—OW1	88.42 (8)	Ca1^iv—O6—Ca1^viii	114.30 (8)
O6^iv—Ca1—OW1	90.64 (8)	C2—C1—C6	120.0 (2)
O3ⁱ—Ca1—O5ⁱⁱⁱ	148.03 (7)	C2—C1—C7	122.6 (2)
O4ⁱⁱ—Ca1—O5ⁱⁱⁱ	91.33 (7)	C6—C1—C7	117.4 (2)
O1—Ca1—O5ⁱⁱⁱ	69.43 (7)	C1—C2—C3	120.3 (2)
O6^iv—Ca1—O5ⁱⁱⁱ	111.71 (7)	C1—C2—H2A	119.8
OW1—Ca1—O5ⁱⁱⁱ	83.12 (7)	C3—C2—H2A	119.8
O3ⁱ—Ca1—Cu1	118.21 (6)	C4—C3—C2	119.6 (2)
O4ⁱⁱ—Ca1—Cu1	110.50 (5)	C4—C3—C8	120.9 (2)
O1—Ca1—Cu1	49.46 (5)	C2—C3—C8	119.2 (2)
O6^iv—Ca1—Cu1	131.04 (6)	C3—C4—C5	120.3 (2)
OW1—Ca1—Cu1	63.49 (6)	C3—C4—H4A	119.9
O5ⁱⁱⁱ—Ca1—Cu1	30.79 (4)	C5—C4—H4A	119.9
O6ⁱⁱⁱ—Ca1—Cu1	73.03 (4)	C6—C5—C4	119.8 (2)
C9ⁱⁱⁱ—Ca1—Cu1	50.47 (5)	C6—C5—C9	118.8 (2)
C8ⁱⁱ—Ca1—Cu1	106.72 (6)	C4—C5—C9	121.4 (2)
O2^v—Cu1—O2	180.000 (1)	C5—C6—C1	119.9 (2)
O2^v—Cu1—O5^vi	91.13 (8)	C5—C6—H6A	120.1
O2—Cu1—O5^vi	88.87 (8)	C1—C6—H6A	120.1
O2^v—Cu1—O5ⁱⁱⁱ	88.87 (8)	O1—C7—O2	123.6 (2)
O2—Cu1—O5ⁱⁱⁱ	91.13 (8)	O1—C7—C1	118.5 (2)
O5^vi—Cu1—O5ⁱⁱⁱ	180.000 (1)	O2—C7—C1	117.8 (2)
O2^v—Cu1—Ca1^v	87.31 (6)	O3—C8—O4	124.8 (2)
O2—Cu1—Ca1^v	92.69 (6)	O3—C8—C3	117.4 (2)
O5^vi—Cu1—Ca1^v	39.61 (5)	O4—C8—C3	117.7 (2)
O5ⁱⁱⁱ—Cu1—Ca1^v	140.39 (5)	O6—C9—O5	120.3 (2)
O2^v—Cu1—Ca1	92.69 (6)	O6—C9—C5	121.0 (2)
O2—Cu1—Ca1	87.31 (6)	O5—C9—C5	118.7 (2)
O5^vi—Cu1—Ca1	140.39 (5)	Ca1—OW1—HW1A	127 (2)
O5ⁱⁱⁱ—Cu1—Ca1	39.61 (5)	Ca1—OW1—HW1B	122 (2)
Ca1^v—Cu1—Ca1	180.0	HW1A—OW1—HW1B	105.9 (16)
C7—O1—Ca1	146.05 (17)

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

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
OW1—HW1A···O4^vi	0.84 (1)	1.95 (1)	2.793 (3)	173 (3)
OW1—HW1B···O2^v	0.84 (1)	2.31 (2)	3.020 (3)	143 (3)

Symmetry codes: (v) −x+1, −y+2, −z+2; (vi) −x+1, −y+1, −z+2.

Funding information

Funding for this research was provided by: National Natural Science Foundation of China (award No. 21271189).

References

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