Poly[di-μ9-citrato-cobalt(II)tetra­sodium]

Liu, Z.; Tian, R.; Mao, R.; Cao, X.; Wang, F.

doi:10.1107/S1600536812017606

metal-organic compounds

CRYSTALLOGRAPHIC
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ISSN: 2056-9890

Volume 68| Part 5| May 2012| Pages m679-m680

doi:10.1107/S1600536812017606

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Poly[di-μ₉-citrato-cobalt(II)tetrasodium]

Zhen Liu,^a Ruijing Tian,^a Rui Mao,^a Xueyin Cao ^a and Fuxiang Wang ^a ^*

^aDepartment of Materials and Chemical Engineering, Ministry of Education Key Laboratory of Advanced Materials of Tropical Island Resources, Hainan University, Haikou 570228, Hainan Province, People's Republic of China
^*Correspondence e-mail: fuxiang.wang@yahoo.com.cn

(Received 30 March 2012; accepted 20 April 2012; online 25 April 2012)

The title compound, [CoNa₄(C₆H₅O₇)₂]_n, was obtained under hydrothermal conditions as a minor product. The Co²⁺ cation is located on a crystallographic inversion center and is coordinated by six O atoms from two different citrate units, forming a [Co(C₆H₅O₇)₂]⁴⁻ building unit with Co—O bond lengths between 2.0578 (17) and 2.0813 (16) Å. The structure features two crystallographically independent Na⁺ ions. The first Na⁺ cation is five-coordinated by O atoms of five carboxylate groups from four different citrate anions. The second Na⁺ cation is surrounded by six O atoms of five carboxylate groups from five different citrate anions. The carboxylate groups of the citrate are completely deprononated, the hydroxyl group, however, is not. It is coordinated to the Co²⁺ cation, and through an O—H⋯O hydrogen bond connected to a neighboring [Co(C₆H₅O₇)₂]⁴⁻ building unit. The coordination modes of the carboxylate O atoms vary, with one O atom being coordinated to three different Na⁺ cations, three are bridging O atoms bound to two Na⁺ cations and two are connected to a Co²⁺ cation and a Na⁺ cation, respectively. Through these interconnections, the basic [Co(C₆H₅O₇)₂]⁴⁻ building units are linked with each other through coordination of their carboxylate groups to the Na⁺ cations, forming a three-dimensional framework.

Related literature

For potential applications of coordination polymers in drug delivery, shape-selective sorption/separation and catalysis, see: Chen & Tong (2007 ); Zeng et al. (2009 ). Their structures vary from one-dimensional to three-dimensional architectures, see: Du & Bu et al. (2009 ); Qiu & Zhu (2009 ). For a compound containing the [Co(C₆H₅O₇)₂]⁴⁻ subunit, see: Matzapetakis et al. (2000 ); for coordination polymers involving Na⁺ cations, see: Pan et al. (2011 ).

Experimental

Crystal data

[CoNa₄(C₆H₅O₇)₂]
M_r = 529.09
Monoclinic, P 2₁ /c
a = 7.9792 (16) Å
b = 12.516 (3) Å
c = 8.7110 (17) Å
β = 113.84 (3)°
V = 795.7 (3) Å³
Z = 2
Mo Kα radiation
μ = 1.28 mm⁻¹
T = 293 K
0.25 × 0.15 × 0.15 mm

Data collection

Rigaku R-AXIS RAPID-S diffractometer
Absorption correction: multi-scan (CrystalClear; Rigaku/MSC, 2002 ) T_min = 0.795, T_max = 0.826
8179 measured reflections
1820 independent reflections
1493 reflections with I > 2σ(I)
R_int = 0.055

Refinement

R[F² > 2σ(F²)] = 0.041
wR(F²) = 0.072
S = 1.12
1820 reflections
142 parameters
H-atom parameters constrained
Δρ_max = 0.29 e Å⁻³
Δρ_min = −0.31 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H1⋯O4ⁱ	0.85	1.79	2.640 (3)	174
Symmetry code: (i) -x+2, -y, -z+1.

Data collection: RAPID-AUTO (Rigaku, 1998 ); cell refinement: RAPID-AUTO; data reduction: CrystalStructure (Rigaku/MSC, 2002); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536812017606/zl2468sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536812017606/zl2468Isup2.hkl

checkCIF report

Comment top

The design and synthesis of coordination polymers have attracted increasing attention in recent years because of their potential applications in drug delivery, shape-selective sorption/separation, and catalysis (Chen et al., 2007, Zeng et al., 2009). Architectures of coordination polymers described vary between one-dimensional and three-dimensional (Qiu et al., 2009, Du et al., 2009). Citric acid and its anions have been widely used as ligands for the construction of coordination polymers, because of their versatility and ability to bind metals with diverse connection modes. In this paper, we present a new three-dimensional coordination polymer [Na₄Co(C₆H₅O₇)₂]_n with citric acid as the ligand.

As shown in Fig. 1, the asymmetric unit of the crystal structure of the title compound consists of half a Co²⁺ center, two Na⁺ cations, and a citrate anion. The Co²⁺ center, located on a crystallographic inversion center, is coordinated by six O atoms from two different citrate units with the Co—O bond distances in the range of 2.0578 (17) to 2.0812 (16) Å, resulting in a slightly distorted octahedral coordination geometry. For the citrate unit, all the carboxylic acid groups are completely deprononated, however the hydroxyl group is not. Three O atoms of each citrate unit are bonded to the Co²⁺ center, one of which is the hydroxy O atom of the citric acid, the other two are from two different carboxylate groups of the citrate ligands. In such a way, two citrate anions and one Co²⁺ cation form a [Co(C₆H₅O₇)₂]^4- building unit such as described previously by Matzapetakis et al. (2000). The citrate anions also coordinate to the Na⁺ cations. Oxygen atom O1 of the hydroxyl group is connected only to the Co cation. Carboxylate oxygen atom O5 is linked to three different Na cations. The other five O atoms are bridging O atoms bound to two Na cations (O3, O4, and O7 atoms) or a Co cation and a Na cation (O2 and O6 atoms), respectively. The two Na⁺ cations display different coordination modes by the O atoms. The Na1⁺ cation is five-coordinated by five O atoms of five carboxylic acid groups from four different citrate units. The Na2⁺ cation, on the other hand, is surrounded by six O atoms of five carboxylic acid groups from five different citrate units. The Na—O bond distances are in the range of 2.286 (2)–2.562 (2) Å, which is in the usual range expected for such a compound (see for example: Pan et al., 2011). In this way, the [Co(C₆H₅O₇)₂]^4- building units are linked with each other through coordination of their carboxylate groups to the Na⁺ cations to form a three-dimensional framework (see Fig. 2).

As shown in Fig. 3, the [Co(C₆H₅O₇)₂]^4- building units are arranged in layers with the Co²⁺ centers located within the bc plane (Co atoms are placed on crystallographic inversion centers at the corners of the unit cell and at the center of the bc plane of the unit cell). Neighboring [Co(C₆H₅O₇)₂]^4- building units are further linked along the c axis to form a one-dimesional chain, and by the O—H···O hydrogen bonds formed by the hydroxyl group and the O4 atom of a neighboring building unit (symmetry code: -x+2, -y, -z+1). The Na⁺ cations are located between adjacent planes of the cobalt building units, and are coordinated by the carboxylate groups of citrate ligands. In such a way a sheet dominated by Na—O ionic interactions is formed, as shown in Fig. 4. The sheets are arranged parallel to those of the Co(C₆H₅O₇)₂]^4- building units perpendicular to the a axis, and are supported by the [Co(C₆H₅O₇)₂]^4- building units to construct the three-dimensional coordination polymer.

Related literature top

For potential applications of coordination polymers in drug delivery, shape-selective sorption/separation and catalysis, see: Chen & Tong (2007); Zeng et al. (2009). Their structures vary from one-dimensional to three-dimensional architectures, see: Du & Bu et al. (2009); Qiu & Zhu (2009). For a compound containing the [Co(C₆H₅O₇)₂]^4- subunit, see: Matzapetakis et al. (2000); for coordination polymers involving Na⁺ cations, see: Pan et al. (2011).

Experimental top

In a typical synthesis, a mixture of Co(OAc)₂.4H₂O (0.08 g), benzene-1,4-dicarboxylic acid (0.042 g), NaOH (0.012 g), citric acid (0.096 g), H₂O (3 ml) and ethanol (7 ml) was added to a 20 ml Teflon-lined stainless steel autoclave and heated at 433 K (160 °C) for 3 days. Yellow block shaped crystals were obtained. yield: ~15% (based on NaOH).

Computing details top

Data collection: RAPID-AUTO (Rigaku, 1998); cell refinement: RAPID-AUTO (Rigaku, 1998); data reduction: CrystalStructure (Rigaku/MSC, 2002); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top

	Fig. 1. A view of the asymmetric unit of complex. Ellipsoids are drawn at the 30% probability level. [Symmetry code: (i) 2-x, -y, 2-z.]
	Fig. 2. A view of the packing along the a axis. Dashed lines indicate hydrogen bonds.
	Fig. 3. A view of the arrangement of the [Co(C₆H₅O₇)₂]^4- building units along the bc palne. Dashed lines indicate hydrogen bonds. Sodium atoms are omitted in this view for clarity.
	Fig. 4. A view of Na—O sheet along the bc plane. Co, C and H atoms are omitted in this view for clarity.

Poly[di-µ₉-citrato-cobalt(II)tetrasodium] top

Crystal data top

[CoNa₄(C₆H₅O₇)₂]	F(000) = 530
M_r = 529.09	D_x = 2.208 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 7365 reflections
a = 7.9792 (16) Å	θ = 3.0–27.5°
b = 12.516 (3) Å	µ = 1.28 mm⁻¹
c = 8.7110 (17) Å	T = 293 K
β = 113.84 (3)°	Block, yellow
V = 795.7 (3) Å³	0.25 × 0.15 × 0.15 mm
Z = 2

Data collection top

Rigaku R-AXIS RAPID-S diffractometer	1820 independent reflections
Radiation source: fine-focus sealed tube	1493 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.055
ω scans	θ_max = 27.5°, θ_min = 3.0°
Absorption correction: multi-scan (CrystalClear; Rigaku/MSC, 2002)	h = −10→10
T_min = 0.795, T_max = 0.826	k = −15→16
8179 measured reflections	l = −11→11

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)] = 0.041	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.072	H-atom parameters constrained
S = 1.12	w = 1/[σ²(F_o²) + (0.0253P)² + 0.3552P] where P = (F_o² + 2F_c²)/3
1820 reflections	(Δ/σ)_max < 0.001
142 parameters	Δρ_max = 0.29 e Å⁻³
0 restraints	Δρ_min = −0.31 e Å⁻³

Crystal data top

[CoNa₄(C₆H₅O₇)₂]	V = 795.7 (3) Å³
M_r = 529.09	Z = 2
Monoclinic, P2₁/c	Mo Kα radiation
a = 7.9792 (16) Å	µ = 1.28 mm⁻¹
b = 12.516 (3) Å	T = 293 K
c = 8.7110 (17) Å	0.25 × 0.15 × 0.15 mm
β = 113.84 (3)°

Data collection top

Rigaku R-AXIS RAPID-S diffractometer	1820 independent reflections
Absorption correction: multi-scan (CrystalClear; Rigaku/MSC, 2002)	1493 reflections with I > 2σ(I)
T_min = 0.795, T_max = 0.826	R_int = 0.055
8179 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.041	0 restraints
wR(F²) = 0.072	H-atom parameters constrained
S = 1.12	Δρ_max = 0.29 e Å⁻³
1820 reflections	Δρ_min = −0.31 e Å⁻³
142 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
Co1	1.0000	0.0000	1.0000	0.01112 (13)
Na1	0.60461 (14)	0.11777 (8)	1.03513 (13)	0.0233 (3)
Na2	0.44536 (14)	0.37904 (8)	0.83883 (13)	0.0219 (3)
O1	1.0085 (2)	0.01241 (12)	0.7650 (2)	0.0125 (4)
H1	0.9089	0.0001	0.6807	0.015*
O2	0.8226 (2)	0.12772 (13)	0.9279 (2)	0.0177 (4)
O3	0.6796 (2)	0.27068 (15)	0.7861 (2)	0.0232 (5)
O4	1.3026 (2)	0.01125 (14)	0.5009 (2)	0.0195 (4)
O5	1.4004 (2)	0.01690 (13)	0.7789 (2)	0.0186 (4)
O6	1.2231 (2)	0.10114 (14)	1.0518 (2)	0.0172 (4)
O7	1.3273 (2)	0.22348 (13)	0.9263 (2)	0.0187 (4)
C1	1.0686 (3)	0.12024 (19)	0.7524 (3)	0.0120 (5)
C2	0.9109 (3)	0.19974 (19)	0.7122 (3)	0.0138 (5)
H2A	0.9616	0.2709	0.7193	0.017*
H2B	0.8274	0.1886	0.5961	0.017*
C3	0.7974 (3)	0.1990 (2)	0.8171 (3)	0.0143 (5)
C4	1.1394 (3)	0.12288 (19)	0.6139 (3)	0.0144 (5)
H4A	1.0377	0.1087	0.5075	0.017*
H4B	1.1833	0.1944	0.6082	0.017*
C5	1.2912 (3)	0.0446 (2)	0.6347 (3)	0.0142 (5)
C6	1.2209 (3)	0.1507 (2)	0.9229 (3)	0.0132 (5)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Co1	0.0127 (2)	0.0116 (2)	0.0100 (2)	0.0002 (2)	0.00553 (18)	0.0019 (2)
Na1	0.0213 (6)	0.0273 (6)	0.0241 (6)	−0.0021 (5)	0.0121 (5)	−0.0007 (5)
Na2	0.0197 (5)	0.0251 (6)	0.0217 (6)	−0.0023 (5)	0.0092 (5)	0.0015 (5)
O1	0.0139 (8)	0.0118 (9)	0.0109 (8)	−0.0036 (7)	0.0041 (7)	−0.0007 (7)
O2	0.0205 (10)	0.0181 (10)	0.0184 (10)	0.0034 (8)	0.0121 (8)	0.0051 (8)
O3	0.0212 (11)	0.0269 (11)	0.0246 (11)	0.0126 (8)	0.0126 (9)	0.0074 (9)
O4	0.0186 (10)	0.0256 (10)	0.0163 (9)	0.0018 (8)	0.0092 (8)	−0.0050 (8)
O5	0.0190 (9)	0.0187 (10)	0.0152 (9)	0.0030 (8)	0.0039 (8)	0.0003 (8)
O6	0.0176 (9)	0.0199 (10)	0.0113 (9)	−0.0018 (8)	0.0028 (7)	0.0032 (8)
O7	0.0179 (10)	0.0176 (9)	0.0219 (10)	−0.0051 (8)	0.0096 (8)	−0.0022 (8)
C1	0.0144 (12)	0.0112 (12)	0.0118 (12)	0.0005 (10)	0.0069 (10)	0.0026 (10)
C2	0.0167 (13)	0.0145 (12)	0.0111 (12)	0.0030 (10)	0.0066 (10)	0.0015 (11)
C3	0.0137 (13)	0.0150 (13)	0.0128 (13)	0.0000 (10)	0.0038 (10)	−0.0023 (11)
C4	0.0167 (13)	0.0151 (13)	0.0125 (13)	0.0032 (10)	0.0072 (11)	0.0015 (11)
C5	0.0139 (13)	0.0135 (12)	0.0160 (14)	−0.0039 (10)	0.0068 (11)	−0.0002 (11)
C6	0.0112 (12)	0.0141 (12)	0.0164 (13)	0.0042 (10)	0.0077 (11)	−0.0021 (11)

Geometric parameters (Å, º) top

Co1—O2ⁱ	2.0578 (17)	O4—C5	1.275 (3)
Co1—O2	2.0578 (17)	O4—Na2^viii	2.542 (2)
Co1—O6	2.0800 (17)	O4—Na2^ix	2.545 (2)
Co1—O6ⁱ	2.0800 (17)	O5—C5	1.254 (3)
Co1—O1	2.0813 (16)	O5—Na1ⁱ	2.349 (2)
Co1—O1ⁱ	2.0813 (16)	O5—Na1^x	2.508 (2)
Na1—O2	2.286 (2)	O5—Na2^viii	2.562 (2)
Na1—O5ⁱ	2.349 (2)	O6—C6	1.276 (3)
Na1—O7ⁱⁱ	2.418 (2)	O6—Na2^xi	2.424 (2)
Na1—O3ⁱⁱⁱ	2.455 (2)	O7—C6	1.238 (3)
Na1—O5ⁱⁱ	2.508 (2)	O7—Na2^x	2.416 (2)
Na2—O7ⁱⁱ	2.416 (2)	O7—Na1^x	2.418 (2)
Na2—O6^iv	2.424 (2)	C1—C4	1.526 (3)
Na2—O3	2.498 (2)	C1—C2	1.530 (3)
Na2—O4^v	2.542 (2)	C1—C6	1.539 (3)
Na2—O4^vi	2.545 (2)	C2—C3	1.525 (3)
Na2—O5^v	2.562 (2)	C2—H2A	0.9700
O1—C1	1.451 (3)	C2—H2B	0.9700
O1—H1	0.8501	C4—C5	1.510 (3)
O2—C3	1.270 (3)	C4—H4A	0.9700
O3—C3	1.247 (3)	C4—H4B	0.9700
O3—Na1^vii	2.455 (2)

O2ⁱ—Co1—O2	180.000 (1)	C3—O3—Na1^vii	119.56 (16)
O2ⁱ—Co1—O6	89.06 (7)	C3—O3—Na2	154.82 (17)
O2—Co1—O6	90.94 (7)	Na1^vii—O3—Na2	85.63 (7)
O2ⁱ—Co1—O6ⁱ	90.94 (7)	C5—O4—Na2^viii	92.53 (15)
O2—Co1—O6ⁱ	89.06 (7)	C5—O4—Na2^ix	122.91 (16)
O6—Co1—O6ⁱ	180.0	Na2^viii—O4—Na2^ix	102.91 (7)
O2ⁱ—Co1—O1	93.79 (7)	C5—O5—Na1ⁱ	133.69 (16)
O2—Co1—O1	86.21 (7)	C5—O5—Na1^x	133.68 (16)
O6—Co1—O1	78.61 (7)	Na1ⁱ—O5—Na1^x	86.18 (7)
O6ⁱ—Co1—O1	101.39 (7)	C5—O5—Na2^viii	92.13 (15)
O2ⁱ—Co1—O1ⁱ	86.21 (7)	Na1ⁱ—O5—Na2^viii	86.42 (6)
O2—Co1—O1ⁱ	93.79 (7)	Na1^x—O5—Na2^viii	116.79 (8)
O6—Co1—O1ⁱ	101.39 (7)	C6—O6—Co1	113.50 (16)
O6ⁱ—Co1—O1ⁱ	78.61 (7)	C6—O6—Na2^xi	127.01 (16)
O1—Co1—O1ⁱ	180.000 (1)	Co1—O6—Na2^xi	119.41 (8)
O2—Na1—O5ⁱ	123.27 (8)	C6—O7—Na2^x	159.49 (17)
O2—Na1—O7ⁱⁱ	122.46 (7)	C6—O7—Na1^x	96.72 (15)
O5ⁱ—Na1—O7ⁱⁱ	113.26 (7)	Na2^x—O7—Na1^x	98.80 (7)
O2—Na1—O3ⁱⁱⁱ	112.38 (8)	O1—C1—C4	108.62 (19)
O5ⁱ—Na1—O3ⁱⁱⁱ	81.95 (7)	O1—C1—C2	110.85 (19)
O7ⁱⁱ—Na1—O3ⁱⁱⁱ	83.86 (7)	C4—C1—C2	109.76 (19)
O2—Na1—O5ⁱⁱ	89.53 (7)	O1—C1—C6	108.27 (19)
O5ⁱ—Na1—O5ⁱⁱ	93.82 (7)	C4—C1—C6	110.9 (2)
O7ⁱⁱ—Na1—O5ⁱⁱ	76.36 (7)	C2—C1—C6	108.40 (19)
O3ⁱⁱⁱ—Na1—O5ⁱⁱ	156.27 (7)	C3—C2—C1	119.5 (2)
O7ⁱⁱ—Na2—O6^iv	101.07 (7)	C3—C2—H2A	107.5
O7ⁱⁱ—Na2—O3	92.10 (7)	C1—C2—H2A	107.5
O6^iv—Na2—O3	98.95 (7)	C3—C2—H2B	107.5
O7ⁱⁱ—Na2—O4^v	132.38 (7)	C1—C2—H2B	107.5
O6^iv—Na2—O4^v	125.90 (7)	H2A—C2—H2B	107.0
O3—Na2—O4^v	88.26 (7)	O3—C3—O2	123.0 (2)
O7ⁱⁱ—Na2—O4^vi	86.60 (7)	O3—C3—C2	116.4 (2)
O6^iv—Na2—O4^vi	102.26 (7)	O2—C3—C2	120.6 (2)
O3—Na2—O4^vi	158.61 (8)	C5—C4—C1	115.2 (2)
O4^v—Na2—O4^vi	77.09 (7)	C5—C4—H4A	108.5
O7ⁱⁱ—Na2—O5^v	168.65 (7)	C1—C4—H4A	108.5
O6^iv—Na2—O5^v	77.74 (7)	C5—C4—H4B	108.5
O3—Na2—O5^v	77.04 (7)	C1—C4—H4B	108.5
O4^v—Na2—O5^v	51.67 (6)	H4A—C4—H4B	107.5
O4^vi—Na2—O5^v	104.71 (7)	O5—C5—O4	123.2 (2)
C1—O1—Co1	106.67 (13)	O5—C5—C4	119.9 (2)
C1—O1—H1	109.0	O4—C5—C4	116.9 (2)
Co1—O1—H1	116.4	O7—C6—O6	124.8 (2)
C3—O2—Co1	131.01 (16)	O7—C6—C1	118.2 (2)
C3—O2—Na1	115.84 (16)	O6—C6—C1	117.0 (2)
Co1—O2—Na1	112.10 (8)

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

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···O4^xii	0.85	1.79	2.640 (3)	174

Symmetry code: (xii) −x+2, −y, −z+1.

Experimental details

Crystal data
Chemical formula	[CoNa₄(C₆H₅O₇)₂]
M_r	529.09
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	293
a, b, c (Å)	7.9792 (16), 12.516 (3), 8.7110 (17)
β (°)	113.84 (3)
V (Å³)	795.7 (3)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	1.28
Crystal size (mm)	0.25 × 0.15 × 0.15

Data collection
Diffractometer	Rigaku R-AXIS RAPID-S diffractometer
Absorption correction	Multi-scan (CrystalClear; Rigaku/MSC, 2002)
T_min, T_max	0.795, 0.826
No. of measured, independent and observed [I > 2σ(I)] reflections	8179, 1820, 1493
R_int	0.055
(sin θ/λ)_max (Å⁻¹)	0.649

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.041, 0.072, 1.12
No. of reflections	1820
No. of parameters	142
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.29, −0.31

Computer programs: RAPID-AUTO (Rigaku, 1998), CrystalStructure (Rigaku/MSC, 2002), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···O4ⁱ	0.85	1.79	2.640 (3)	174.1

Symmetry code: (i) −x+2, −y, −z+1.

Acknowledgements

This work was supported by the National Natural Science Foundation of China (No. 21101047), the Natural Science Foundation of Hainan Province (No. 211010) and the Priming Scientific Research Foundation of Hainan University (No. kyqd1112).

References

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