metal-organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

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ISSN: 2056-9890
Volume 69| Part 4| April 2013| Pages m219-m220

Poly[μ-aqua-aqua-μ4-naphthalene-1,8-di­carboxyl­ato-barium]: a layer structure

aDepartment of Physics and Chemistry, Henan Polytechnic University, Jiaozuo, Henan 454000, People's Republic of China
*Correspondence e-mail: iamzd@hpu.edu.cn

(Received 28 January 2013; accepted 5 March 2013; online 16 March 2013)

The title compound, [Ba(C12H6O4)(H2O)2]n, is represented by a layer-like structure built of BaO8 polyhedra. The asymmetric unit contains a Ba2+ ion, half a coordinating water mol­ecule and half a μ4-bridging naphthalene-1,8-dicarboxyl­ate (1,8-nap) ligand, the whole structure being generated by twofold rotational symmetry. The carboxyl­ate groups of the 1,8-nap ligands act as bridges linking four Ba2+ ions, while each Ba2+ ion is eight-coordinated by O atoms from four 1,8-nap ligands and two coordinating water mol­ecules. In the crystal, there are O—H⋯O hydrogen bonds involving the water mol­ecules and carboxyl­ate O atoms in the BaO8 polyhedra. Each BaO8 polyhedron is connected via corner-sharing water O atoms or edge-sharing ligand O atoms, forming a sheet parallel to the bc plane. These sheets stack along the a-axis direction and are connected via van der Waals forces only. The naphthalene groups protrude above and below the layers of the BaO8 polyhedra and there are voids of ca 208 Å3 bounded by these groups. No residual electron density was found in this region. The crystal studied was twinned by pseudo-merohedry, with a refined twin component ratio of 0.5261 (1):0.4739 (1).

Related literature

For other compounds based on 1,8-nap ligands, see: Wen et al. (2007[Wen, Y.-H., Feng, X., He, Y.-H., Lan, Y.-Z. & Sun, H. (2007). Acta Cryst. C63, m504-m506.], 2008[Wen, Y. H., Feng, X., Feng, Y. L., Lan, Y. Z. & Yao, Y. G. (2008). Inorg. Chem. Commun. 11, 659-661.]); Zhang et al. (2008[Zhang, G.-Y., Zhang, X. & Yu, G.-S. (2008). Acta Cryst. E64, m214.]); Fu et al. (2011[Fu, J. D., Ye, L. Q., Zhang, C. Y. & Wen, Y. H. (2011). Chin. J. Inorg. Chem. 27, 179-183.]).

[Scheme 1]

Experimental

Crystal data
  • [Ba(C12H6O4)(H2O)2]

  • Mr = 369.52

  • Orthorhombic, I b c a

  • a = 8.9643 (11) Å

  • b = 30.539 (6) Å

  • c = 8.9625 (12) Å

  • V = 2453.6 (7) Å3

  • Z = 8

  • Mo Kα radiation

  • μ = 3.25 mm−1

  • T = 296 K

  • 0.20 × 0.05 × 0.05 mm

Data collection
  • Bruker APEXII CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 1996[Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany.]) Tmin = 0.563, Tmax = 0.855

  • 7968 measured reflections

  • 1511 independent reflections

  • 1344 reflections with I > 2σ(I)

  • Rint = 0.035

Refinement
  • R[F2 > 2σ(F2)] = 0.019

  • wR(F2) = 0.043

  • S = 1.05

  • 1511 reflections

  • 85 parameters

  • H-atom parameters constrained

  • Δρmax = 0.54 e Å−3

  • Δρmin = −0.57 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O3—H3⋯O2i 0.86 2.07 2.777 (2) 140
Symmetry code: (i) -x+1, -y, -z.

Data collection: APEX2 (Bruker, 2008[Bruker (2008). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2008[Bruker (2008). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: Mercury (Macrae et al., 2008[Macrae, C. F., Bruno, I. J., Chisholm, J. A., Edgington, P. R., McCabe, P., Pidcock, E., Rodriguez-Monge, L., Taylor, R., van de Streek, J. & Wood, P. A. (2008). J. Appl. Cryst. 41, 466-470.]); software used to prepare material for publication: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]).

Supporting information


Comment top

In recent years, supramolecular assembles based on polyoxometalates (POMs) have been intensively investigated in many field such as catalysis, electrical conductivity, and biological chemistry. The ligand naphthalene-1,8-dicarboxylic (1,8-nap) has been used extensively to construct a number of metal organic complexes (Wen et al., 2007,2008; Zhang et al., 2008), including the related barium compound Ba(C12H6O4) [Fu et al., 2011]. To prepare a new barium complex incorporating 1,8-nap ligand, we have synthesized the title compound and report herein on its crystal structure.

The title compound is a non-interpenetrating two-dimensional layer-like structure consisting of BaO8 clusters, which are similar to the reported compound Ba(C12H6O4) [Fu et al., 2011]. As shown in Fig. 1 the asymmetric unit of the title complex contains one crystallographically independent Ba atom, one coordination water molecule and a half 1,8-nap ligand. Each barium atom is eight-coordinated by O atoms in a square antiprismatic geometry, in which six oxygen atoms come from four 1,8-nap ligands (two of them adopt a chelate connection) and two oxygen atoms come from two coordinated water molecules. The Ba–O bond distances range from 2.723 (2) to 2.8806 (14) Å, in which the Ba1–O3 water bond gives the longest bond distance.

The 1,8-nap ligands are not planar, with the carboxylate groups and the naphthalene ring dihedral angles being 49.0 (3)° and 52.4 (3)°, respectively. The carboxylate groups of the 1,8-nap ligand act as µ2-bridges to link four Ba atoms. Furthermore, each BaO8 polyhedra is connected via corner-sharing H2O oxygen atoms or edge-sharing ligand oxygen atoms to form a two-dimensional sheet parallel to the bc plane. All Ba atoms in the two-dimensional layer are coplanar, with adjacent Ba···Ba distance of 4.4821 (6), 4.9292 (6) and 5.0972 (6) Å.

By considering the Ba atoms as the nodes, this two-dimensional layered structure can be topologically represented as a 6-connected (3,6) net.

In the crystal, there are O-H···O hydrogen bonds involving the water molecules and the carboxylate O atoms in the BaO8 clusters (Fig. 2 and Table 1). There are no π-π stacking interactions, only van der Waals forces are present between the layers that stack along the a direction. The naphthalene groups protrude above and below the layers of the BaO8 clusters and there are voids of ca. 208 Å3 bounded by these groups. No residual electron density was found in this region.

Related literature top

For other compounds based on 1,8-nap ligands, see: Wen et al. (2007, 2008); Zhang et al. (2008); Fu et al. (2011).

Experimental top

A mixture of naphthalene-1,8-dicarboxylic (0.2 g), BaCO3 (0.05 g) and H2O (15 ml) was heated at 443 K for 3 d in a sealed 25 ml Teflon-lined stainless steel vessel under autogenous pressure. After cooling to room temperature at a rate of 20°C h-1, colourless prismatic crystals suitable for single-crystal X-ray diffraction analysis were obtained in low yield.

Refinement top

The crystal is a pseudo-merohedral twin, with twin law (00-1, 0-10, -100) giving an ca. 1:1 ratio of twin moieties [refined BASF value = 0.5261 (1)]. The C-bound H atoms were positioned geometrically and refined with a riding model: C—H = 0.93 Å with Uiso(H) = 1.2Ueq(C). The water H atoms were located in difference Fourier maps and refined initially with distance restraints: O–H = 0.86 Å, then as riding atoms with Uiso(H) = 1.2Ueq(O).

Computing details top

Data collection: APEX2 (Bruker, 2008); cell refinement: SAINT (Bruker, 2008); data reduction: SAINT (Bruker, 2008); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: Mercury (Macrae et al., 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound showing the coordination environment of the Ba atom. Displacement ellipsoids are drawn at the 50% probability level
[Figure 2] Fig. 2. A view along the a axis of the crystal packing of the title compound. The O-H···O hydrogen bonds are shown as red dashed lines (see Table 1 for details).
Poly[µ-aqua-aqua-µ4-naphthalene-1,8-dicarboxylato-barium] top
Crystal data top
[Ba(C12H6O4)(H2O)2]F(000) = 1408
Mr = 369.52Dx = 2.001 Mg m3
Orthorhombic, IbcaMo Kα radiation, λ = 0.71073 Å
Hall symbol: -I 2b 2cCell parameters from 2836 reflections
a = 8.9643 (11) Åθ = 2.7–27.1°
b = 30.539 (6) ŵ = 3.25 mm1
c = 8.9625 (12) ÅT = 296 K
V = 2453.6 (7) Å3Prism, colourless
Z = 80.20 × 0.05 × 0.05 mm
Data collection top
Bruker APEXII CCD area-detector
diffractometer
1511 independent reflections
Radiation source: fine-focus sealed tube1344 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.035
Detector resolution: 83.33 pixels mm-1θmax = 28.4°, θmin = 1.3°
ω scansh = 115
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
k = 4038
Tmin = 0.563, Tmax = 0.855l = 1110
7968 measured reflections
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)] = 0.019Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.043H-atom parameters constrained
S = 1.05 w = 1/[σ2(Fo2) + (0.0197P)2 + 0.1976P]
where P = (Fo2 + 2Fc2)/3
1511 reflections(Δ/σ)max = 0.001
85 parametersΔρmax = 0.54 e Å3
0 restraintsΔρmin = 0.57 e Å3
Crystal data top
[Ba(C12H6O4)(H2O)2]V = 2453.6 (7) Å3
Mr = 369.52Z = 8
Orthorhombic, IbcaMo Kα radiation
a = 8.9643 (11) ŵ = 3.25 mm1
b = 30.539 (6) ÅT = 296 K
c = 8.9625 (12) Å0.20 × 0.05 × 0.05 mm
Data collection top
Bruker APEXII CCD area-detector
diffractometer
1511 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
1344 reflections with I > 2σ(I)
Tmin = 0.563, Tmax = 0.855Rint = 0.035
7968 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0190 restraints
wR(F2) = 0.043H-atom parameters constrained
S = 1.05Δρmax = 0.54 e Å3
1511 reflectionsΔρmin = 0.57 e Å3
85 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
xyzUiso*/Ueq
Ba10.61452 (2)0.00000.25000.02892 (7)
O10.4190 (2)0.05878 (6)0.5240 (3)0.0360 (5)
C10.3754 (3)0.07360 (9)0.4035 (4)0.0236 (6)
O20.3671 (2)0.05119 (7)0.2858 (2)0.0341 (5)
C20.3410 (3)0.12190 (9)0.3935 (3)0.0253 (6)
O30.75000.04396 (9)0.00000.0418 (8)
H30.71970.05940.07420.050*
C30.25000.14342 (12)0.50000.0239 (8)
C40.25000.19041 (12)0.50000.0324 (10)
C50.3323 (4)0.21277 (11)0.3902 (5)0.0486 (10)
H50.33250.24320.38990.058*
C60.4105 (4)0.19121 (11)0.2860 (4)0.0527 (10)
H60.46100.20670.21230.063*
C70.4163 (4)0.14507 (10)0.2877 (3)0.0386 (8)
H70.47200.13030.21600.046*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Ba10.01894 (11)0.03182 (12)0.03599 (14)0.0000.0000.00999 (13)
O10.0321 (12)0.0315 (11)0.0445 (13)0.0027 (9)0.0065 (10)0.0124 (10)
C10.0140 (12)0.0213 (14)0.0356 (16)0.0012 (10)0.0042 (11)0.0009 (12)
O20.0330 (11)0.0314 (11)0.0380 (14)0.0029 (8)0.0096 (8)0.0132 (9)
C20.0279 (15)0.0225 (15)0.0255 (15)0.0033 (12)0.0016 (11)0.0004 (12)
O30.0412 (19)0.0472 (18)0.037 (2)0.0000.0162 (15)0.000
C30.025 (2)0.0220 (19)0.025 (2)0.0000.0046 (16)0.000
C40.034 (2)0.022 (2)0.041 (3)0.0000.0010 (19)0.000
C50.061 (2)0.0203 (17)0.065 (3)0.0016 (16)0.0042 (19)0.0087 (16)
C60.067 (2)0.0326 (18)0.058 (3)0.0034 (16)0.0213 (19)0.0164 (15)
C70.0463 (18)0.0366 (17)0.033 (2)0.0007 (14)0.0128 (13)0.0060 (13)
Geometric parameters (Å, º) top
Ba1—O1i2.723 (2)C2—C71.362 (4)
Ba1—O1ii2.723 (2)C2—C31.417 (3)
Ba1—O2iii2.7324 (19)O3—Ba1viii2.8806 (14)
Ba1—O22.7324 (19)O3—H30.8587
Ba1—O2iv2.7703 (19)C3—C2ix1.417 (3)
Ba1—O2v2.7703 (19)C3—C41.435 (5)
Ba1—O3vi2.8806 (14)C4—C5ix1.407 (4)
Ba1—O32.8806 (14)C4—C51.407 (4)
O1—C11.234 (4)C5—C61.341 (5)
O1—Ba1ii2.723 (2)C5—H50.9300
C1—O21.259 (4)C6—C71.410 (4)
C1—C21.509 (4)C6—H60.9300
O2—Ba1vii2.7703 (19)C7—H70.9300
O1i—Ba1—O1ii167.34 (9)O2iv—Ba1—Ba1vii144.82 (4)
O1i—Ba1—O2iii101.55 (6)O2v—Ba1—Ba1vii144.82 (4)
O1ii—Ba1—O2iii67.71 (6)O3vi—Ba1—Ba1vii114.937 (13)
O1i—Ba1—O267.71 (6)O3—Ba1—Ba1vii114.937 (13)
O1ii—Ba1—O2101.55 (6)C1iii—Ba1—Ba1vii50.87 (4)
O2iii—Ba1—O271.48 (8)C1—Ba1—Ba1vii50.87 (4)
O1i—Ba1—O2iv68.40 (6)O1i—Ba1—Ba1iv96.33 (4)
O1ii—Ba1—O2iv123.25 (6)O1ii—Ba1—Ba1iv96.33 (4)
O2iii—Ba1—O2iv166.59 (9)O2iii—Ba1—Ba1iv144.26 (4)
O2—Ba1—O2iv110.74 (7)O2—Ba1—Ba1iv144.26 (4)
O1i—Ba1—O2v123.25 (6)O2iv—Ba1—Ba1iv35.18 (4)
O1ii—Ba1—O2v68.40 (6)O2v—Ba1—Ba1iv35.18 (4)
O2iii—Ba1—O2v110.74 (7)O3vi—Ba1—Ba1iv65.063 (13)
O2—Ba1—O2v166.59 (9)O3—Ba1—Ba1iv65.063 (13)
O2iv—Ba1—O2v70.35 (8)C1iii—Ba1—Ba1iv129.13 (4)
O1i—Ba1—O3vi108.54 (7)C1—Ba1—Ba1iv129.13 (4)
O1ii—Ba1—O3vi77.00 (7)Ba1vii—Ba1—Ba1iv180.0
O2iii—Ba1—O3vi134.45 (5)C1—O1—Ba1ii149.05 (19)
O2—Ba1—O3vi89.09 (5)O1—C1—O2123.5 (3)
O2iv—Ba1—O3vi58.83 (5)O1—C1—C2118.3 (3)
O2v—Ba1—O3vi80.11 (6)O2—C1—C2118.0 (3)
O1i—Ba1—O377.00 (7)O1—C1—Ba184.93 (16)
O1ii—Ba1—O3108.54 (7)O2—C1—Ba148.58 (13)
O2iii—Ba1—O389.09 (5)C2—C1—Ba1138.71 (18)
O2—Ba1—O3134.45 (5)C1—O2—Ba1111.20 (16)
O2iv—Ba1—O380.11 (6)C1—O2—Ba1vii116.85 (16)
O2v—Ba1—O358.83 (5)Ba1—O2—Ba1vii109.08 (7)
O3vi—Ba1—O3130.13 (3)C7—C2—C3120.9 (3)
O1i—Ba1—C1iii93.75 (7)C7—C2—C1116.6 (3)
O1ii—Ba1—C1iii78.20 (7)C3—C2—C1122.1 (3)
O2iii—Ba1—C1iii20.22 (6)Ba1viii—O3—Ba1124.44 (10)
O2—Ba1—C1iii85.06 (6)Ba1viii—O3—H377.7
O2iv—Ba1—C1iii147.38 (7)Ba1—O3—H3136.4
O2v—Ba1—C1iii100.91 (6)C2—C3—C2ix124.8 (3)
O3vi—Ba1—C1iii152.80 (6)C2—C3—C4117.62 (17)
O3—Ba1—C1iii69.07 (6)C2ix—C3—C4117.62 (17)
O1i—Ba1—C178.20 (7)C5ix—C4—C5121.9 (4)
O1ii—Ba1—C193.75 (7)C5ix—C4—C3119.0 (2)
O2iii—Ba1—C185.06 (6)C5—C4—C3119.0 (2)
O2—Ba1—C120.22 (6)C6—C5—C4121.6 (3)
O2iv—Ba1—C1100.91 (6)C6—C5—H5119.2
O2v—Ba1—C1147.38 (7)C4—C5—H5119.2
O3vi—Ba1—C169.07 (6)C5—C6—C7120.2 (3)
O3—Ba1—C1152.80 (6)C5—C6—H6119.9
C1iii—Ba1—C1101.74 (9)C7—C6—H6119.9
O1i—Ba1—Ba1vii83.67 (4)C2—C7—C6120.5 (3)
O1ii—Ba1—Ba1vii83.67 (4)C2—C7—H7119.7
O2iii—Ba1—Ba1vii35.74 (4)C6—C7—H7119.7
O2—Ba1—Ba1vii35.74 (4)
Symmetry codes: (i) x+1, y, z1/2; (ii) x+1, y, z+1; (iii) x, y, z+1/2; (iv) x+1/2, y, z+1/2; (v) x+1/2, y, z; (vi) x+3/2, y, z+1/2; (vii) x1/2, y, z+1/2; (viii) x+3/2, y, z1/2; (ix) x+1/2, y, z+1.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O3—H3···O2x0.862.072.777 (2)140
Symmetry code: (x) x+1, y, z.

Experimental details

Crystal data
Chemical formula[Ba(C12H6O4)(H2O)2]
Mr369.52
Crystal system, space groupOrthorhombic, Ibca
Temperature (K)296
a, b, c (Å)8.9643 (11), 30.539 (6), 8.9625 (12)
V3)2453.6 (7)
Z8
Radiation typeMo Kα
µ (mm1)3.25
Crystal size (mm)0.20 × 0.05 × 0.05
Data collection
DiffractometerBruker APEXII CCD area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 1996)
Tmin, Tmax0.563, 0.855
No. of measured, independent and
observed [I > 2σ(I)] reflections
7968, 1511, 1344
Rint0.035
(sin θ/λ)max1)0.669
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.019, 0.043, 1.05
No. of reflections1511
No. of parameters85
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.54, 0.57

Computer programs: APEX2 (Bruker, 2008), SAINT (Bruker, 2008), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), Mercury (Macrae et al., 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O3—H3···O2i0.862.072.777 (2)140
Symmetry code: (i) x+1, y, z.
 

Acknowledgements

The authors acknowledge the Doctoral Foundation of Henan Polytechnic University (B2010–92, 648483).

References

First citationBruker (2008). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
First citationFu, J. D., Ye, L. Q., Zhang, C. Y. & Wen, Y. H. (2011). Chin. J. Inorg. Chem. 27, 179–183.  CAS Google Scholar
First citationMacrae, C. F., Bruno, I. J., Chisholm, J. A., Edgington, P. R., McCabe, P., Pidcock, E., Rodriguez-Monge, L., Taylor, R., van de Streek, J. & Wood, P. A. (2008). J. Appl. Cryst. 41, 466–470.  Web of Science CrossRef CAS IUCr Journals Google Scholar
First citationSheldrick, G. M. (1996). SADABS. University of Göttingen, Germany.  Google Scholar
First citationSheldrick, G. M. (2008). Acta Cryst. A64, 112–122.  Web of Science CrossRef CAS IUCr Journals Google Scholar
First citationWen, Y. H., Feng, X., Feng, Y. L., Lan, Y. Z. & Yao, Y. G. (2008). Inorg. Chem. Commun. 11, 659–661.  Web of Science CSD CrossRef CAS Google Scholar
First citationWen, Y.-H., Feng, X., He, Y.-H., Lan, Y.-Z. & Sun, H. (2007). Acta Cryst. C63, m504–m506.  Web of Science CSD CrossRef IUCr Journals Google Scholar
First citationZhang, G.-Y., Zhang, X. & Yu, G.-S. (2008). Acta Cryst. E64, m214.  Web of Science CSD CrossRef IUCr Journals Google Scholar

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Volume 69| Part 4| April 2013| Pages m219-m220
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