supplementary materials


hy2639 scheme

Acta Cryst. (2013). E69, m672    [ doi:10.1107/S1600536813030067 ]

Poly[di-[mu]9-citrato-tetra­sodiumzinc]

Y.-H. Ma, H.-W. Yang, J.-T. Hao, P.-Z. Ma and T. Yao

Abstract top

In the title compound, [Na4Zn(C6H5O7)2]n, the ZnII ion lies on an inversion center and is coordinated by six O atoms from two citrate ligands, forming a distorted octa­hedral geometry. There are two crystallographically independent Na+ cations in the asymmetric unit. One Na+ cation exhibits a distorted square-pyramidal geometry defined by five O atoms from four citrate ligands. The other Na+ cation is surrounded by six O atoms from five citrate ligands in a distorted octa­hedral geometry. The Na+ cations are bridged by citrate carboxyl­ate groups, forming a layer parallel to (100). The layers are further assembled into a three-dimensional network with the [Zn(citrate)2]4- building units as `pillars'; O-H...O hydrogen bonds also stabilize the structure.

Comment top

Citric acid has been widely used for the construction of coordination polymers due to their diverse coordination modes (Liu et al., 2012). Here, we report a new three-dimensional coordination polymer, [Na4Zn(C6H5O7)2]n, based on citric acid.

As shown in Fig. 1, the asymmetric unit of the title compound consists of half a ZnII ion, two Na+ cations and a citrate anion. The ZnII ion lies on a crystallographic inversion center and is coordinated by six O atoms from two different citrate ligands, forming a distorted octahedral geometry. Three O atoms of each citrate ligand are bonded to the ZnII ion, one of which is the hydroxy O atom and the other two are from different carboxylate groups. Thus, two citrate ligands and one ZnII ion form a [Zn(C6H5O7)2]4- building unit. This unit bridges sixteen Na+ cations (Fig. 2). Na1 exhibits a distorted square-pyramidal geometry, defined by five O atoms from four different citrate ligands. Na2 is surrounded by six O atoms from five different citrate ligands, building a distorted octahedral geometry. The Na+ cations are bridged by carboxylate groups from the citrate ligands into a two-dimensional layer parallel to (100) (Fig. 3). The layers are further assembled into a three-dimensional network through [Zn(C6H5O7)2]4- building units as 'pillars' (Fig. 4).

Related literature top

For an isotypic compound, see: Liu et al. (2012).

Experimental top

A mixture of citric acid (0.2 mmol), NaOH (0.2 mmol) and zinc nitrate hexahydrate (0.1 mmol) was dissolved in DMAC/H2O solvent (5 ml, v/v = 1:4) (DMAC = N,N'-dimethylacetamide) and placed in a capped vial (10 ml), which was heated to 363 K for three days and then cooled to room temperature. The crystals obtained were washed with water and dried in air.

Refinement top

C-bound H atoms were placed at calculated positions and refined as riding atoms, with C—H = 0.97 Å and with Uiso(H) = 1.2Ueq(C). The hydroxy H atom was located in a difference map and refined isotropically.

Computing details top

Data collection: CrystalClear (Rigaku, 2005); cell refinement: CrystalClear (Rigaku, 2005); data reduction: CrystalClear (Rigaku, 2005); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: XP in SHELXTL (Sheldrick, 2008) and DIAMOND (Brandenburg, 1999); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The asymmetric unit of the title compound, showing the 30% probability displacement ellipsoids. [Symmetry code: (i) 1-x, 2-y, 1-z.]
[Figure 2] Fig. 2. The [Zn(C6H5O7)2]4- building unit bridges sixteen Na+ cations.
[Figure 3] Fig. 3. A view of the two-dimensional layer in the bc plane.
[Figure 4] Fig. 4. A view of the three-dimensional network in the title compound.
Poly[di-µ9-citrato-tetrasodiumzinc] top
Crystal data top
[Na4Zn(C6H5O7)2]F(000) = 536
Mr = 535.55Dx = 2.234 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 7740 reflections
a = 7.9642 (16) Åθ = 3.0–27.5°
b = 12.530 (3) ŵ = 1.74 mm1
c = 8.7090 (17) ÅT = 293 K
β = 113.66 (3)°Block, colorless
V = 796.0 (3) Å30.21 × 0.21 × 0.20 mm
Z = 2
Data collection top
Rigaku SCXmini CCD
diffractometer
1831 independent reflections
Radiation source: fine-focus sealed tube1570 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.048
ω scanθmax = 27.5°, θmin = 3.0°
Absorption correction: multi-scan
(ABSCOR; Higashi, 1995)
h = 1010
Tmin = 0.712, Tmax = 0.722k = 1616
8270 measured reflectionsl = 1111
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.037Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.075H atoms treated by a mixture of independent and constrained refinement
S = 1.15 w = 1/[σ2(Fo2) + (0.0289P)2 + 0.3351P]
where P = (Fo2 + 2Fc2)/3
1831 reflections(Δ/σ)max = 0.001
145 parametersΔρmax = 0.37 e Å3
0 restraintsΔρmin = 0.47 e Å3
Crystal data top
[Na4Zn(C6H5O7)2]V = 796.0 (3) Å3
Mr = 535.55Z = 2
Monoclinic, P21/cMo Kα radiation
a = 7.9642 (16) ŵ = 1.74 mm1
b = 12.530 (3) ÅT = 293 K
c = 8.7090 (17) Å0.21 × 0.21 × 0.20 mm
β = 113.66 (3)°
Data collection top
Rigaku SCXmini CCD
diffractometer
1831 independent reflections
Absorption correction: multi-scan
(ABSCOR; Higashi, 1995)
1570 reflections with I > 2σ(I)
Tmin = 0.712, Tmax = 0.722Rint = 0.048
8270 measured reflectionsθmax = 27.5°
Refinement top
R[F2 > 2σ(F2)] = 0.037H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.075Δρmax = 0.37 e Å3
S = 1.15Δρmin = 0.47 e Å3
1831 reflectionsAbsolute structure: ?
145 parametersAbsolute structure parameter: ?
0 restraintsRogers parameter: ?
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
xyzUiso*/Ueq
O70.4930 (2)0.98761 (13)0.7363 (2)0.0127 (4)
O30.2766 (2)0.89905 (13)0.4482 (2)0.0178 (4)
O40.1751 (2)0.77628 (13)0.5749 (2)0.0175 (4)
O60.8225 (3)0.72885 (15)0.7149 (2)0.0233 (4)
O50.6783 (2)0.87114 (13)0.5716 (2)0.0175 (4)
C80.7041 (3)0.8007 (2)0.6829 (3)0.0141 (5)
C40.2806 (3)0.84956 (19)0.5774 (3)0.0124 (5)
C50.5911 (3)0.80021 (19)0.7885 (3)0.0132 (5)
H5A0.67480.81180.90420.016*
H5B0.54070.72910.78220.016*
C30.4328 (3)0.87982 (18)0.7479 (3)0.0118 (5)
C20.3615 (3)0.87711 (19)0.8861 (3)0.0144 (5)
H2A0.31800.80560.89200.017*
H2B0.46290.89160.99230.017*
O20.1969 (2)0.98895 (14)0.9984 (2)0.0179 (4)
Zn10.50001.00000.50000.01321 (12)
Na20.05408 (14)1.12137 (8)0.83937 (13)0.0216 (3)
Na10.10230 (14)1.11830 (8)0.53517 (13)0.0222 (3)
O10.1002 (2)0.98321 (13)0.7212 (2)0.0186 (4)
C10.2085 (3)0.95534 (19)0.8644 (3)0.0131 (5)
H10.606 (4)1.000 (2)0.828 (4)0.016*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O70.0154 (9)0.0111 (9)0.0118 (9)0.0021 (7)0.0057 (7)0.0007 (7)
O30.0185 (9)0.0207 (10)0.0114 (9)0.0038 (8)0.0030 (8)0.0027 (7)
O40.0173 (9)0.0160 (9)0.0210 (10)0.0047 (7)0.0095 (8)0.0030 (7)
O60.0225 (10)0.0256 (11)0.0245 (11)0.0128 (8)0.0123 (9)0.0071 (8)
O50.0223 (10)0.0168 (9)0.0180 (9)0.0037 (7)0.0127 (8)0.0041 (7)
C80.0123 (12)0.0156 (13)0.0137 (12)0.0008 (10)0.0045 (10)0.0014 (10)
C40.0110 (12)0.0132 (12)0.0151 (12)0.0031 (9)0.0072 (10)0.0014 (9)
C50.0145 (12)0.0127 (12)0.0131 (12)0.0023 (10)0.0065 (10)0.0017 (9)
C30.0136 (12)0.0104 (11)0.0123 (12)0.0003 (9)0.0062 (10)0.0028 (9)
C20.0155 (12)0.0160 (13)0.0134 (13)0.0014 (10)0.0076 (11)0.0024 (10)
O20.0176 (9)0.0229 (10)0.0162 (9)0.0018 (8)0.0098 (8)0.0047 (7)
Zn10.0152 (2)0.0130 (2)0.0124 (2)0.00022 (17)0.00663 (17)0.00209 (16)
Na20.0197 (5)0.0236 (6)0.0216 (6)0.0023 (4)0.0084 (5)0.0013 (4)
Na10.0208 (6)0.0253 (6)0.0223 (6)0.0022 (4)0.0105 (5)0.0007 (4)
O10.0178 (9)0.0208 (10)0.0159 (9)0.0024 (7)0.0053 (8)0.0006 (7)
C10.0134 (12)0.0113 (11)0.0165 (13)0.0039 (10)0.0080 (11)0.0011 (10)
Geometric parameters (Å, º) top
O7—C31.450 (3)O2—Na22.539 (2)
O7—Zn12.0866 (17)Zn1—O5iv2.0742 (17)
O3—C41.274 (3)Zn1—O3iv2.0796 (17)
O3—Zn12.0796 (17)Zn1—O7iv2.0866 (17)
O3—Na2i2.432 (2)Na2—O4v2.415 (2)
O4—C41.239 (3)Na2—O3i2.432 (2)
O4—Na2ii2.415 (2)Na2—O6vi2.478 (2)
O4—Na1i2.417 (2)Na2—O2vii2.548 (2)
O6—C81.251 (3)Na2—O12.565 (2)
O6—Na1iii2.443 (2)Na1—O5iv2.288 (2)
O6—Na2iii2.478 (2)Na1—O12.348 (2)
O5—C81.266 (3)Na1—O4i2.417 (2)
O5—Zn12.0742 (17)Na1—O6vi2.443 (2)
O5—Na1iv2.288 (2)Na1—O1i2.512 (2)
C8—C51.523 (3)Na1—C4i2.833 (3)
C8—Na1iv3.061 (3)Na1—C8iv3.061 (3)
C4—C31.540 (3)O1—C11.248 (3)
C4—Na1i2.833 (3)O7—H10.95 (3)
C5—C31.534 (3)C2—H2A0.97
C3—C21.523 (3)C2—H2B0.97
C2—C11.516 (3)C5—H5A0.97
O2—C11.279 (3)C5—H5B0.97
C3—O7—Zn1106.16 (13)Na1—Na2—Na1viii102.34 (4)
C4—O3—Zn1112.86 (16)O4v—Na2—Na2vii113.39 (6)
C4—O3—Na2i127.44 (16)O3i—Na2—Na2vii120.36 (6)
Zn1—O3—Na2i119.59 (8)O6vi—Na2—Na2vii125.52 (7)
C4—O4—Na2ii160.44 (17)O2—Na2—Na2vii38.48 (4)
C4—O4—Na1i96.18 (14)O2vii—Na2—Na2vii38.32 (4)
Na2ii—O4—Na1i98.47 (7)O1—Na2—Na2vii76.31 (5)
C8—O6—Na1iii119.97 (16)Na1—Na2—Na2vii120.15 (4)
C8—O6—Na2iii154.24 (17)Na1viii—Na2—Na2vii114.57 (5)
Na1iii—O6—Na2iii85.80 (7)O5iv—Na1—O1122.68 (8)
C8—O5—Zn1130.84 (16)O5iv—Na1—O4i122.16 (7)
C8—O5—Na1iv115.86 (16)O1—Na1—O4i114.15 (7)
Zn1—O5—Na1iv112.04 (8)O5iv—Na1—O6vi112.02 (8)
O6—C8—O5123.2 (2)O1—Na1—O6vi82.02 (7)
O6—C8—C5116.0 (2)O4i—Na1—O6vi84.37 (8)
O5—C8—C5120.8 (2)O5iv—Na1—O1i89.47 (7)
O4—C4—O3124.7 (2)O1—Na1—O1i93.91 (7)
O4—C4—C3117.7 (2)O4i—Na1—O1i76.45 (7)
O3—C4—C3117.6 (2)O6vi—Na1—O1i156.79 (8)
C8—C5—C3119.2 (2)O5iv—Na1—C4i137.95 (8)
O7—C3—C2108.32 (19)O1—Na1—C4i92.09 (8)
O7—C3—C5110.93 (19)O4i—Na1—C4i25.78 (6)
C2—C3—C5109.63 (19)O6vi—Na1—C4i94.17 (8)
O7—C3—C4108.45 (18)O1i—Na1—C4i63.03 (7)
C2—C3—C4110.9 (2)O5iv—Na1—C8iv21.85 (6)
C5—C3—C4108.56 (19)O1—Na1—C8iv144.32 (8)
C1—C2—C3115.0 (2)O4i—Na1—C8iv100.39 (7)
C1—O2—Na292.67 (15)O6vi—Na1—C8iv111.12 (7)
C1—O2—Na2vii122.64 (15)O1i—Na1—C8iv85.42 (7)
Na2—O2—Na2vii103.20 (7)C4i—Na1—C8iv118.60 (8)
O5iv—Zn1—O5180.0O5iv—Na1—Na1i112.02 (7)
O5iv—Zn1—O3iv90.85 (7)O1—Na1—Na1i49.04 (5)
O5—Zn1—O3iv89.15 (7)O4i—Na1—Na1i96.43 (6)
O5iv—Zn1—O389.15 (7)O6vi—Na1—Na1i126.69 (7)
O5—Zn1—O390.85 (7)O1i—Na1—Na1i44.88 (5)
O3iv—Zn1—O3180.000 (1)C4i—Na1—Na1i71.49 (6)
O5iv—Zn1—O7iv86.09 (7)C8iv—Na1—Na1i120.93 (7)
O5—Zn1—O7iv93.91 (7)O5iv—Na1—Na2155.15 (7)
O3iv—Zn1—O7iv79.02 (7)O1—Na1—Na249.81 (5)
O3—Zn1—O7iv100.98 (7)O4i—Na1—Na274.74 (5)
O5iv—Zn1—O793.91 (7)O6vi—Na1—Na247.54 (5)
O5—Zn1—O786.09 (7)O1i—Na1—Na2113.50 (6)
O3iv—Zn1—O7100.98 (7)C4i—Na1—Na265.27 (6)
O3—Zn1—O779.02 (7)C8iv—Na1—Na2157.96 (6)
O7iv—Zn1—O7180.000 (1)Na1i—Na1—Na281.11 (4)
O5iv—Zn1—Na135.88 (5)O5iv—Na1—Zn132.08 (5)
O5—Zn1—Na1144.12 (5)O1—Na1—Zn190.68 (6)
O3iv—Zn1—Na1115.73 (5)O4i—Na1—Zn1151.83 (6)
O3—Zn1—Na164.27 (5)O6vi—Na1—Zn1113.43 (6)
O7iv—Zn1—Na1115.05 (6)O1i—Na1—Zn189.37 (5)
O7—Zn1—Na164.95 (6)C4i—Na1—Zn1152.38 (6)
O5iv—Zn1—Na1iv144.12 (5)C8iv—Na1—Zn153.66 (5)
O5—Zn1—Na1iv35.88 (5)Na1i—Na1—Zn190.01 (4)
O3iv—Zn1—Na1iv64.27 (5)Na2—Na1—Zn1133.42 (4)
O3—Zn1—Na1iv115.73 (5)O5iv—Na1—Na2ix86.09 (5)
O7iv—Zn1—Na1iv64.95 (6)O1—Na1—Na2ix150.32 (6)
O7—Zn1—Na1iv115.05 (6)O4i—Na1—Na2ix40.74 (5)
Na1—Zn1—Na1iv180.0O6vi—Na1—Na2ix79.96 (6)
O4v—Na2—O3i100.76 (7)O1i—Na1—Na2ix93.45 (6)
O4v—Na2—O6vi92.41 (7)C4i—Na1—Na2ix66.06 (6)
O3i—Na2—O6vi98.70 (7)C8iv—Na1—Na2ix64.99 (5)
O4v—Na2—O2132.94 (7)Na1i—Na1—Na2ix131.30 (6)
O3i—Na2—O2125.58 (7)Na2—Na1—Na2ix101.14 (3)
O6vi—Na2—O288.62 (7)Zn1—Na1—Na2ix118.12 (3)
O4v—Na2—O2vii86.70 (7)C1—O1—Na1134.25 (16)
O3i—Na2—O2vii102.18 (7)C1—O1—Na1i133.31 (16)
O6vi—Na2—O2vii158.90 (8)Na1—O1—Na1i86.09 (7)
O2—Na2—O2vii76.80 (7)C1—O1—Na292.17 (15)
O4v—Na2—O1168.90 (7)Na1—O1—Na285.84 (6)
O3i—Na2—O177.54 (7)Na1i—O1—Na2117.27 (8)
O6vi—Na2—O177.12 (7)O1—C1—O2123.1 (2)
O2—Na2—O151.60 (6)O1—C1—C2120.3 (2)
O2vii—Na2—O1104.40 (7)O2—C1—C2116.6 (2)
O4v—Na2—Na1125.09 (6)Zn1—O7—H1115 (2)
O3i—Na2—Na162.16 (5)C3—O7—H1108.9 (16)
O6vi—Na2—Na146.67 (5)C1—C2—H2A109
O2—Na2—Na187.87 (5)C1—C2—H2B109
O2vii—Na2—Na1145.37 (6)C3—C2—H2A108
O1—Na2—Na144.35 (5)C3—C2—H2B109
O4v—Na2—Na1viii40.79 (5)H2A—C2—H2B108
O3i—Na2—Na1viii123.00 (6)C3—C5—H5A107
O6vi—Na2—Na1viii57.61 (5)C3—C5—H5B108
O2—Na2—Na1viii106.39 (6)C8—C5—H5A107
O2vii—Na2—Na1viii111.68 (5)C8—C5—H5B108
O1—Na2—Na1viii131.31 (6)H5A—C5—H5B107
Symmetry codes: (i) x, y+2, z+1; (ii) x, y1/2, z+3/2; (iii) x+1, y1/2, z+3/2; (iv) x+1, y+2, z+1; (v) x, y+1/2, z+3/2; (vi) x+1, y+1/2, z+3/2; (vii) x, y+2, z+2; (viii) x, y+5/2, z+1/2; (ix) x, y+5/2, z1/2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O7—H1···O2x0.95 (3)1.69 (3)2.635 (2)174 (3)
Symmetry code: (x) x+1, y+2, z+2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O7—H1···O2i0.95 (3)1.69 (3)2.635 (2)174 (3)
Symmetry code: (i) x+1, y+2, z+2.
Acknowledgements top

The authors acknowledge the Air Force Service College for supporting this work.

references
References top

Brandenburg, K. (1999). DIAMOND. Crystal Impact GbR, Bonn, Germany.

Higashi, T. (1995). ABSCOR. Rigaku Corporation, Tokyo, Japan.

Liu, Z., Tian, R., Mao, R., Cao, X. & Wang, F. (2012). Acta Cryst. E68, m679–m680.

Rigaku (2005). CrystalClear. Rigaku Corporation, Tokyo, Japan.

Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122.