Poly[[octaaqua-μ4-(benzene-1,2,4,5-tetra­carboxyl­ato)-dicobalt(II)] octa­hydrate]

Camara, M.; Tine, M.; Daiguebonne, C.; Guillou, O.; Roisnel, T.

doi:10.1107/S1600536813031577

metal-organic compounds

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ISSN: 2056-9890

Volume 69| Part 12| December 2013| Pages m680-m681

doi:10.1107/S1600536813031577

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Poly[[octaaqua-μ₄-(benzene-1,2,4,5-tetracarboxylato)-dicobalt(II)] octahydrate]

Magatte Camara,^a ^* Modou Tine,^a Carole Daiguebonne,^b Olivier Guillou ^b and Thierry Roisnel ^c

^aUniversité Assane Seck de Ziguinchor, LCPM, Groupe Matériaux Inorganiques, Chimie Douce et Cristallographie, BP 523 Ziguinchor, Senegal, ^bINSA, UMR 6226, Institut des Sciences Chimiques de Rennes, 35708 Rennes, France, and ^cInstitut des Sciences Chimiques de Rennes, UMR CNRS 6226, Université de Rennes I, Avenue du Général Leclerc, 35042 Rennes Cedex, France
^*Correspondence e-mail: mcamara@univ-zig.sn

(Received 10 October 2013; accepted 19 November 2013; online 23 November 2013)

The title polymeric coordination compound, {[Co₂(C₁₀H₂O₈)(H₂O)₈]·8H₂O}_n, was obtained by slow diffusion of a dilute aqueous solution of CoCl₂ and the sodium salt of benzene-1,2,4,5-tetracarboxylic acid (H₄btec) through an agar–agar gel bridge in a U-shaped tube. The two independent Co²⁺ ions are each situated on an inversion centre and are coordinated in a slightly distorted octahedral geometry by four water O atoms and two carboxylate O atoms from two btec⁴⁻ ligands (-1> symmetry), forming a layer parallel to (11-1). This layer can be described as a molecular two-dimensional square grid with the benzene rings at the nodes and the Co^II atoms connecting the nodes. O—H⋯O hydrogen-bonding interactions involving the coordinating water molecules, the carboxylate O atoms and lattice water molecules lead to the formation of a three-dimensional network.

CCDC reference: 965872

Related literature

For related metal-organic materials with large channels and cavities, see: Yaghi et al. (1998 ); Evans et al. (1999 ); Eddaoudi et al. (2002 ); Guillou et al. (2006 ). For examples of coordination polymers containing the btec⁴⁻ ligand, see: Cheng et al. (2000 ); Rochon & Massarweh (2000 ); Chu et al. (2001 ); Wu et al. (2002 ); Luo et al. (2013 ). For related crystal-growth methods in gels, see: Henisch & Rustum (1970 ); Henisch (1988 ); Daiguebonne et al. (2003 ).

Experimental

Crystal data

[Co₂(C₁₀H₂O₈)(H₂O)₈]·8H₂O
M_r = 656.22
Triclinic, $[P \overline 1]$
a = 5.4371 (1) Å
b = 9.8496 (3) Å
c = 10.2564 (3) Å
α = 96.445 (1)°
β = 91.232 (1)°
γ = 91.328 (1)°
V = 545.48 (3) Å³
Z = 1
Mo Kα radiation
μ = 1.64 mm⁻¹
T = 298 K
0.10 × 0.09 × 0.06 mm

Data collection

Bruker APEXII diffractometer
8487 measured reflections
2456 independent reflections
2092 reflections with I > 2σ(I)
R_int = 0.025

Refinement

R[F² > 2σ(F²)] = 0.048
wR(F²) = 0.153
S = 0.97
2456 reflections
166 parameters
H-atom parameters constrained
Δρ_max = 0.60 e Å⁻³
Δρ_min = −0.81 e Å⁻³

Table 1
Selected bond lengths (Å)

Co1—O1	2.084 (3)
Co1—O3	2.089 (3)
Co1—O23	2.106 (2)
Co2—O2	2.101 (3)
Co2—O4	2.060 (3)
Co2—O12	2.122 (2)

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O3—H1⋯O11ⁱ	0.79	1.92	2.698 (4)	169
O4—H4⋯O14	0.82	1.89	2.636 (9)	150
O4—H4⋯O16	0.82	1.92	2.632 (10)	143
O1—H5⋯O23ⁱⁱ	0.89	1.87	2.746 (4)	171
O2—H6⋯O12ⁱⁱⁱ	0.89	1.92	2.803 (4)	177
O1—H7⋯O22^iv	0.75	1.97	2.664 (4)	154
O2—H9⋯O22	0.90	1.82	2.725 (4)	176
O3—H10⋯O14	0.73	1.95	2.682 (9)	176
O3—H10⋯O15^v	0.73	2.32	2.848 (9)	130
O4—H13⋯O11^vi	0.73	1.94	2.618 (5)	154
Symmetry codes: (i) x, y+1, z; (ii) -x+1, -y, -z+1; (iii) x-1, y, z; (iv) -x, -y, -z+1; (v) x+1, y, z; (vi) -x, -y-1, -z.

Data collection: APEX2 (Bruker, 2007 ); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL2013 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg, 1999 ); software used to prepare material for publication: publCIF (Westrip, 2010 ).

Supporting information

CCDC reference: 965872

Crystal structure: contains datablock I. DOI: 10.1107/S1600536813031577/vn2077sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536813031577/vn2077Isup2.hkl

checkCIF report

Comment top

The design of metal-organic materials with large channels and cavities has been deeply investigated, due to their intriguing structural diversity and potential functions as microporous solids for molecular adsorption, ion exchange, and heterogeneous catalysis. For related structures in this context, see: Yaghi et al., 1998; Evans et al., 1999; Eddaoudi et al., 2002; Guillou et al., 2006. The benzene-1,2,4,5-tetracarboxylate ligand (btec^4-) as a multi-connecting ligand is an excellent candidate for the design of coordination polymers. Surprisingly, examples of coordination polymers involving this ligand are relatively scarce. For examples of coordination polymers with this ligand, see: Cheng et al., 2000; Chu et al., 2001; Rochon & Massarweh, 2000; Wu et al., 2002; Luo et al., 2013). We report here the synthesis and the crystal structure of the title coordination polymer.

All carboxylic groups of the organic ligand in the title compound are deprotonated and each of them adopts a monodentate coordination mode. There are two crystallographically independent Co^II atoms in the structure. In both cases the Co^II atoms are coordinated by two carboxylate oxygen atoms from two btec ligands and four water oxygen atoms (Fig. 1). There is no significant difference in the coordination distance between carboxyl and water oxygen atoms. The coordination Co···O distances in the title polymeric compound range from 2.067 (3) to 2.129 (3) Å. Each btec^4- ligand links four Co^II atoms and each Co^II atom is bond to two btec^4- ligands to form a two-dimensional layer. These layers can be described as a molecular two-dimensional square grid in which the phenyl rings are at the nodes and the Co^II atoms connecting the nodes (Fig. 2). The area of the square cells of the grids is larger than 120 Å² (11.3 Å x 11.5 Å). The crystal packing is enforced by a complex hydrogen bonds network that involves the crystallization water molecules located in the inter-layer space.

Related literature top

For related metal-organic materials with large channels and cavities, see: Yaghi et al. (1998); Evans et al. (1999); Eddaoudi et al. (2002); Guillou et al. (2006). For examples of coordination polymers containing the btec^4- ligand, see: Cheng et al. (2000); Rochon & Massarweh (2000); Chu et al. (2001); Wu et al. (2002); Luo et al. (2013). For related crystal methods in gels, see: Henisch & Rustum (1970); Henisch (1988); Daiguebonne et al. (2003).

Experimental top

All reagents were used as obtained without further purification. Cobalt chloride was purchased from STREM Chemicals. benzene-1,2,4,5-tetracarboxylic acid was purchased from Acros Organics. Its sodium salt was prepared by addition of four equivalents of sodium hydroxide to a suspension of benzene-1,2,4,5-tetracaboxylic acid in de-ionized water until complete dissolution. Then, the solution was evaporated to dryness. The solid phase was then put in suspension in ethanol, stirred and refluxed during 1 h. After filtration and drying in a desiccator, a white powder of tetra-sodium benzene-1,2,4,5-tetracarboxylate was obtained. The yield of this synthesis is 90%.

Single crystals of the coordination polymer were obtained by slow diffusion of dilute aqueous solutions of Co(II) chloride (0.25 mmol in 20 ml) and of sodium salt of benzene-1,2,4,5-tetracarboxylic acid (0.25 mmol in 20 mL) through an agar-agar gel bridge in a U-shaped tube. The gel was purchased from Acros Organics and jellified according to established procedure. For a related procedure, see: Henisch & Rustum, 1970; Henisch, 1988; Daiguebonne et al., 2003. After several weeks, very light pink single crystals were obtained.

Computing details top

Data collection: APEX2 (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2013 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg, 1999); software used to prepare material for publication: publCIF (Westrip, 2010).

Figures top

	Fig. 1. Extended asymetric unit of the title compound, with the atom-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level. [Symmetry codes: (i) -x, -y, -z + 1; (ii) -x, -y - 1, -z; (iii) -x + 1, -y - 1, -z + 1.]
	Fig. 2. View along the a axis of the molecular square grid layer of the title compound.

Poly[[octaaqua-µ₄-(benzene-1,2,4,5-tetracarboxylato)-dicobalt(II)] octahydrate] top

Crystal data top

[Co₂(C₁₀H₂O₈)(H₂O)₈]·8H₂O	V = 545.48 (3) Å³
M_r = 656.22	Z = 1
Triclinic, P1	F(000) = 340
a = 5.4371 (1) Å	D_x = 1.998 Mg m⁻³
b = 9.8496 (3) Å	Mo Kα radiation, λ = 0.71073 Å
c = 10.2564 (3) Å	µ = 1.64 mm⁻¹
α = 96.445 (1)°	T = 298 K
β = 91.232 (1)°	Prism, very light pink
γ = 91.328 (1)°	0.10 × 0.09 × 0.06 mm

Data collection top

Bruker APEXII diffractometer	2092 reflections with I > 2σ(I)
Radiation source: Fine-focus sealed tube	R_int = 0.025
Graphite monochromator	θ_max = 27.5°, θ_min = 2.0°
CCD rotation images, thin slices scans	h = −6→7
8487 measured reflections	k = −12→12
2456 independent reflections	l = −13→13

Refinement top

Refinement on F²	0 restraints
Least-squares matrix: full	Hydrogen site location: difference Fourier map
R[F² > 2σ(F²)] = 0.048	H-atom parameters constrained
wR(F²) = 0.153	w = 1/[σ²(F_o²) + (0.0911P)² + 2.3818P] where P = (F_o² + 2F_c²)/3
S = 0.97	(Δ/σ)_max < 0.001
2456 reflections	Δρ_max = 0.60 e Å⁻³
166 parameters	Δρ_min = −0.81 e Å⁻³

Crystal data top

[Co₂(C₁₀H₂O₈)(H₂O)₈]·8H₂O	γ = 91.328 (1)°
M_r = 656.22	V = 545.48 (3) Å³
Triclinic, P1	Z = 1
a = 5.4371 (1) Å	Mo Kα radiation
b = 9.8496 (3) Å	µ = 1.64 mm⁻¹
c = 10.2564 (3) Å	T = 298 K
α = 96.445 (1)°	0.10 × 0.09 × 0.06 mm
β = 91.232 (1)°

Data collection top

Bruker APEXII diffractometer	2092 reflections with I > 2σ(I)
8487 measured reflections	R_int = 0.025
2456 independent reflections

Refinement top

R[F² > 2σ(F²)] = 0.048	0 restraints
wR(F²) = 0.153	H-atom parameters constrained
S = 0.97	Δρ_max = 0.60 e Å⁻³
2456 reflections	Δρ_min = −0.81 e Å⁻³
166 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.

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

	x	y	z	U_iso*/U_eq
H1	0.0869	0.1434	0.3071	0.050*
H13	0.0780	−0.2852	−0.0807	0.050*
H4	0.2169	−0.2460	0.0208	0.050*
H5	0.4549	0.1226	0.5668	0.050*
H6	−0.4194	−0.4465	0.1454	0.050*
H7	0.2609	0.1784	0.6194	0.050*
H9	−0.1925	−0.3972	0.2127	0.050*
H10	0.1381	0.0269	0.2641	0.050*
Co1	0.0000	0.0000	0.5000	0.0165 (2)
Co2	0.0000	−0.5000	0.0000	0.0180 (2)
O22	−0.0419 (5)	−0.3362 (3)	0.3694 (3)	0.0246 (6)
O12	0.2439 (5)	−0.5016 (3)	0.1641 (3)	0.0212 (6)
O23	0.2189 (5)	−0.1729 (3)	0.4617 (3)	0.0224 (6)
O11	0.0733 (6)	−0.6758 (3)	0.2541 (3)	0.0352 (8)
O1	0.3013 (5)	0.1098 (3)	0.5906 (3)	0.0308 (7)
O2	−0.2644 (6)	−0.4222 (4)	0.1330 (3)	0.0399 (8)
C1	0.3561 (6)	−0.5310 (4)	0.3841 (3)	0.0159 (7)
O3	0.0735 (7)	0.0657 (3)	0.3177 (3)	0.0381 (8)
C3	0.5172 (7)	−0.6259 (4)	0.4275 (3)	0.0170 (7)
H3	0.5283	−0.7109	0.3786	0.020*
C2	0.3387 (6)	−0.4025 (3)	0.4587 (3)	0.0150 (7)
C22	0.1578 (6)	−0.2968 (4)	0.4251 (3)	0.0158 (7)
C11	0.2111 (7)	−0.5719 (4)	0.2586 (3)	0.0180 (7)
O4	0.1143 (9)	−0.3016 (4)	−0.0152 (4)	0.0596 (13)
O14	0.2936 (16)	−0.0732 (8)	0.1144 (8)	0.121 (3)
O16	0.5551 (16)	−0.1850 (8)	0.0171 (9)	0.121 (3)
O15	−0.4581 (14)	0.0456 (9)	0.1989 (8)	0.116 (2)
O17	0.8066 (16)	−0.0714 (9)	0.1011 (8)	0.124 (3)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Co1	0.0162 (4)	0.0120 (3)	0.0218 (4)	0.0031 (2)	−0.0002 (3)	0.0034 (3)
Co2	0.0196 (4)	0.0198 (4)	0.0146 (3)	−0.0009 (3)	−0.0048 (2)	0.0036 (3)
O22	0.0202 (13)	0.0222 (13)	0.0296 (14)	0.0064 (10)	−0.0078 (11)	−0.0047 (11)
O12	0.0217 (13)	0.0263 (14)	0.0160 (12)	−0.0007 (11)	−0.0063 (10)	0.0054 (10)
O23	0.0186 (13)	0.0124 (12)	0.0362 (15)	0.0043 (10)	−0.0029 (11)	0.0023 (11)
O11	0.051 (2)	0.0243 (15)	0.0307 (16)	−0.0129 (14)	−0.0227 (14)	0.0108 (12)
O1	0.0192 (14)	0.0204 (14)	0.0511 (19)	0.0020 (11)	−0.0027 (12)	−0.0030 (13)
O2	0.0224 (15)	0.073 (3)	0.0221 (15)	0.0016 (15)	−0.0025 (11)	−0.0034 (15)
C1	0.0176 (16)	0.0160 (16)	0.0140 (15)	0.0013 (13)	−0.0038 (12)	0.0022 (13)
O3	0.064 (2)	0.0211 (15)	0.0307 (16)	0.0035 (14)	0.0150 (15)	0.0072 (12)
C3	0.0207 (17)	0.0121 (15)	0.0175 (16)	0.0027 (13)	−0.0029 (13)	−0.0011 (12)
C2	0.0161 (16)	0.0131 (15)	0.0161 (16)	0.0032 (12)	−0.0009 (12)	0.0027 (12)
C22	0.0155 (16)	0.0162 (16)	0.0157 (16)	0.0032 (13)	0.0000 (12)	0.0014 (13)
C11	0.0217 (17)	0.0147 (16)	0.0173 (17)	0.0063 (13)	−0.0062 (13)	0.0003 (13)
O4	0.099 (3)	0.045 (2)	0.0354 (19)	−0.040 (2)	−0.038 (2)	0.0205 (16)
O14	0.141 (7)	0.106 (6)	0.112 (6)	−0.001 (5)	0.012 (5)	−0.009 (4)
O16	0.127 (6)	0.106 (5)	0.131 (6)	−0.003 (5)	−0.023 (5)	0.025 (5)
O15	0.105 (5)	0.146 (7)	0.101 (5)	0.022 (5)	−0.002 (4)	0.022 (5)
O17	0.142 (7)	0.127 (6)	0.101 (5)	0.020 (5)	−0.017 (5)	0.004 (5)

Geometric parameters (Å, º) top

Co1—O1	2.084 (3)	Co2—O12	2.122 (2)
Co1—O1ⁱ	2.084 (3)	O22—C22	1.249 (4)
Co1—O3	2.089 (3)	O12—C11	1.266 (5)
Co1—O3ⁱ	2.089 (3)	O23—C22	1.270 (4)
Co1—O23	2.106 (2)	O11—C11	1.250 (5)
Co1—O23ⁱ	2.106 (2)	C1—C3	1.398 (5)
Co2—O2	2.101 (3)	C1—C2	1.410 (5)
Co2—O4	2.060 (3)	C1—C11	1.505 (5)
Co2—O4ⁱⁱ	2.061 (3)	C3—C2ⁱⁱⁱ	1.390 (5)
Co2—O2ⁱⁱ	2.101 (3)	C2—C3ⁱⁱⁱ	1.390 (5)
Co2—O12ⁱⁱ	2.122 (2)	C2—C22	1.511 (5)

O1—Co1—O1ⁱ	180.0	O2ⁱⁱ—Co2—O12ⁱⁱ	87.12 (11)
O1—Co1—O3	92.62 (14)	O2—Co2—O12ⁱⁱ	92.88 (11)
O1ⁱ—Co1—O3	87.38 (14)	O4—Co2—O12	88.91 (12)
O1—Co1—O3ⁱ	87.38 (14)	O4ⁱⁱ—Co2—O12	91.09 (12)
O1ⁱ—Co1—O3ⁱ	92.62 (14)	O2ⁱⁱ—Co2—O12	92.88 (11)
O3—Co1—O3ⁱ	180.0	O2—Co2—O12	87.12 (11)
O1—Co1—O23	90.10 (11)	O12ⁱⁱ—Co2—O12	180.0
O1ⁱ—Co1—O23	89.90 (11)	C11—O12—Co2	124.9 (2)
O3—Co1—O23	92.24 (12)	C22—O23—Co1	130.4 (2)
O3ⁱ—Co1—O23	87.76 (12)	C3—C1—C2	118.8 (3)
O1—Co1—O23ⁱ	89.90 (11)	C3—C1—C11	117.7 (3)
O1ⁱ—Co1—O23ⁱ	90.10 (11)	C2—C1—C11	123.5 (3)
O3—Co1—O23ⁱ	87.76 (12)	C2ⁱⁱⁱ—C3—C1	122.2 (3)
O3ⁱ—Co1—O23ⁱ	92.24 (12)	C3ⁱⁱⁱ—C2—C1	119.0 (3)
O23—Co1—O23ⁱ	180.0	C3ⁱⁱⁱ—C2—C22	118.1 (3)
O4—Co2—O4ⁱⁱ	180.0	C1—C2—C22	122.8 (3)
O4—Co2—O2ⁱⁱ	91.81 (19)	O22—C22—O23	124.9 (3)
O4ⁱⁱ—Co2—O2ⁱⁱ	88.19 (19)	O22—C22—C2	118.8 (3)
O4—Co2—O2	88.19 (19)	O23—C22—C2	116.2 (3)
O4ⁱⁱ—Co2—O2	91.81 (19)	O11—C11—O12	124.9 (3)
O2ⁱⁱ—Co2—O2	180.0	O11—C11—C1	117.4 (3)
O4—Co2—O12ⁱⁱ	91.09 (12)	O12—C11—C1	117.7 (3)
O4ⁱⁱ—Co2—O12ⁱⁱ	88.91 (12)

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

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O3—H1···O11^iv	0.79	1.92	2.698 (4)	169
O4—H4···O14	0.82	1.89	2.636 (9)	150
O4—H4···O16	0.82	1.92	2.632 (10)	143
O1—H5···O23^v	0.89	1.87	2.746 (4)	171
O2—H6···O12^vi	0.89	1.92	2.803 (4)	177
O1—H7···O22ⁱ	0.75	1.97	2.664 (4)	154
O2—H9···O22	0.90	1.82	2.725 (4)	176
O3—H10···O14	0.73	1.95	2.682 (9)	176
O3—H10···O15^vii	0.73	2.32	2.848 (9)	130
O4—H13···O11ⁱⁱ	0.73	1.94	2.618 (5)	154

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

Selected bond lengths (Å) top

Co1—O1	2.084 (3)	Co2—O2	2.101 (3)
Co1—O3	2.089 (3)	Co2—O4	2.060 (3)
Co1—O23	2.106 (2)	Co2—O12	2.122 (2)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O3—H1···O11ⁱ	0.79	1.92	2.698 (4)	169
O4—H4···O14	0.82	1.89	2.636 (9)	150
O4—H4···O16	0.82	1.92	2.632 (10)	143
O1—H5···O23ⁱⁱ	0.89	1.87	2.746 (4)	171
O2—H6···O12ⁱⁱⁱ	0.89	1.92	2.803 (4)	177
O1—H7···O22^iv	0.75	1.97	2.664 (4)	154
O2—H9···O22	0.90	1.82	2.725 (4)	176
O3—H10···O14	0.73	1.95	2.682 (9)	176
O3—H10···O15^v	0.73	2.32	2.848 (9)	130
O4—H13···O11^vi	0.73	1.94	2.618 (5)	154

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

Acknowledgements

The French Cooperation Agency in Senegal is acknowledged for financial support.

References

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