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

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ISSN: 2056-9890

Poly[di­aqua-μ4-oxalato-di-μ6-phosphato-tetra­cobalt(II)]

aDepartment of Applied Chemistry, College of Science, Nanjing University of Technology, Nanjing 210009, People's Republic of China, and bCenter of Chemical Laboratory, College of Science, Nanjing University of Technology, Nanjing 210009, People's Republic of China
*Correspondence e-mail: wwy@njut.edu.cn

(Received 15 November 2007; accepted 25 January 2008; online 30 January 2008)

In the structure of the title compound, [Co4(C2O4)(PO4)2(H2O)2]n, there are layers composed of the phosphate anions and two independent CoII cations. These layers are parallel to (001) and are bridged by the oxalate anions that are situated in special positions on centres of symmetry. One independent Co atom has an octa­hedral coordination, while the second independent Co atom is coordinated in a trigonal–bipyramidal coordination that includes the water mol­ecule. The crystal packing is stabilized by O—H⋯O hydrogen bonds between the coordinated water mol­ecules and oxalate O atoms.

Related literature

For general background, see Lethbridge et al. (2004[Lethbridge, Z. A. D., Smith, M. J., Tiwary, S. K., Harrison, A. & Lightfoot, P. (2004). Inorg. Chem. 43, 11-13.]). For the related structure (C4N2H12)0.5[Co2(HPO4)(C2O4)1.5], which also contains the unusual CoO5 trigonal–bipyramidal configuration, see Choudhury & Natarajan (2000[Choudhury, A. & Natarajan, S. (2000). Solid State Sci. 2, 365-372.]). For the O—H⋯O hydrogen bonding, see Desiraju & Steiner (1999[Desiraju, G. R. & Steiner, T. (1999). The Weak Hydrogen Bond, p. 13. New York: Oxford University Press Inc.]).

[Scheme 1]

Experimental

Crystal data
  • [Co4(C2O4)(PO4)2(H2O)2]

  • Mr = 549.72

  • Monoclinic, P 21 /n

  • a = 7.8541 (17) Å

  • b = 4.7829 (10) Å

  • c = 14.057 (3) Å

  • β = 95.937 (4)°

  • V = 525.2 (2) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 6.60 mm−1

  • T = 293 (2) K

  • 0.32 × 0.20 × 0.10 mm

Data collection
  • Bruker SMART APEX CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2000[Bruker (2000). SADABS (Version 2.03), SAINT-Plus (Version 6) and SMART (Version 5.0). Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.22, Tmax = 0.52

  • 2798 measured reflections

  • 1133 independent reflections

  • 913 reflections with I > 2σ(I)

  • Rint = 0.034

Refinement
  • R[F2 > 2σ(F2)] = 0.040

  • wR(F2) = 0.094

  • S = 1.09

  • 1133 reflections

  • 107 parameters

  • 3 restraints

  • All H-atom parameters refined

  • Δρmax = 0.90 e Å−3

  • Δρmin = −0.81 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O7—H2⋯O6i 0.84 (2) 1.94 (3) 2.665 (5) 144 (5)
O7—H1⋯O6ii 0.84 (2) 2.46 (4) 3.188 (5) 145 (5)
Symmetry codes: (i) [-x+{\script{3\over 2}}, y-{\script{1\over 2}}, -z+{\script{3\over 2}}]; (ii) [-x+{\script{3\over 2}}, y+{\script{1\over 2}}, -z+{\script{3\over 2}}].

Data collection: SMART (Bruker, 2000[Bruker (2000). SADABS (Version 2.03), SAINT-Plus (Version 6) and SMART (Version 5.0). Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SMART; data reduction: SAINT-Plus (Bruker, 2000[Bruker (2000). SADABS (Version 2.03), SAINT-Plus (Version 6) and SMART (Version 5.0). Bruker AXS Inc., Madison, Wisconsin, USA.]); program(s) used to solve structure: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.

Supporting information


Comment top

A new class of metal phosphate-oxalates framework structures has been discovered in recent years. In this new class the anions [PO4]3- (or [HPO4]2-) and [C2O4]2- act as bridging groups that link up with the metal atoms. Both main-group metals (Al, Ga, In, Sn) and transition metals (V, Mn, Fe, Co, Mo) are reported in these systems (Lethbridge et al., 2004). Among these, to the best of our knowledge there is only one example containing CoII: [C4N2H12]0.5[Co2(HPO4)(C2O4)1.5] (Choudhury & Natarajan, 2000). Here we report the synthesis and the crystal structure of a new oxalate phosphate framework structure containing CoII, [Co4(C2O4)(PO4)2(H2O)2].

The asymmetric unit of the title structure contains two independent Co cations (Fig. 1). Co1 is octahedrally coordinated by six oxygen atoms and Co2 is coordinated by 5 O atoms in a trigonal-bipyramidal configuration. Each phosphate acts as a multiple bridging group, binding six Co atoms to compose the inorganic layer structure. The oxalate group is situated on an inversion centre and links up with two adjacent inorganic layers. The water molecule is coordinated to Co2 (Fig. 2).

Related literature top

For general background, see Lethbridge et al. (2004). For the related structure (C4N2H12)0.5[Co2(HPO4)(C2O4)1.5], which also contains the unusual CoO5 trigonal–bipyramidal configuration, see Choudhury & Natarajan (2000). For the O—H···O hydrogen bonding, see Desiraju & Steiner (1999).

Experimental top

A mixture of Co(ClO4)2.6H2O (0.1830 g, 0.5 mmol), H2C2O4.2H2O (0.2521 g, 2 mmol), Na4P2O7.10H2O (0.8921 g, 2 mmol) and distilled water (10 ml) was placed into a 23 ml teflon-lined autoclave. The mixture was then heated for 72 h at 425 K. The insoluble purple crystals of the title structure were separated by filtration. The crystals were of rectangular plate-like shape with the average size of 0.4 × 0.3 × 0.1 mm.

Refinement top

The H atoms from the water molecule were located in the difference Fourier map and refined with the distance restraints O—H=0.84 (1), H—H=1.33 (2) Å, and with Uiso(H)=1.5Ueq(O).

Computing details top

Data collection: SMART (Bruker, 2000); cell refinement: SMART (Bruker, 2000); data reduction: SAINT-Plus (Bruker, 2000); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. Coordination environment of Co and P atoms in the title structure. The displacement ellipsoids are shown at the 50% probability level. [Symmetry codes: (i) 1 - x, 1 - y, 2 - z; (ii) x, 1 + y, z; (iii) 1/2 - x, 1/2 + y, 3/2 - z; (iv) 3/2 - x, 1/2 + y, 3/2 - z; (v) 3/2 - x, -1/2 + y, 3/2 - z.]
[Figure 2] Fig. 2. The packing of the title structure viewed down the b axis, showing the cobalt phosphate layers bridged by the oxalate ligands. The hydrogen bonds are shown as dashed lines.
Poly[diaqua-µ4-oxalato-di-µ6-phosphato-tetracobalt(II)] top
Crystal data top
[Co4(C2O4)(PO4)2(H2O)2]F(000) = 532
Mr = 549.72Dx = 3.476 Mg m3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 897 reflections
a = 7.8541 (17) Åθ = 2.9–27.0°
b = 4.7829 (10) ŵ = 6.60 mm1
c = 14.057 (3) ÅT = 293 K
β = 95.937 (4)°Plate, purple
V = 525.2 (2) Å30.32 × 0.20 × 0.10 mm
Z = 2
Data collection top
Bruker SMART APEX CCD area-detector
diffractometer
1133 independent reflections
Radiation source: fine-focus sealed tube913 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.034
ϕ and ω scansθmax = 27.0°, θmin = 2.9°
Absorption correction: multi-scan
(SADABS; Bruker, 2000)
h = 910
Tmin = 0.22, Tmax = 0.52k = 66
2798 measured reflectionsl = 1017
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.040All H-atom parameters refined
wR(F2) = 0.094 w = 1/[σ2(Fo2) + (0.0537P)2]
where P = (Fo2 + 2Fc2)/3
S = 1.09(Δ/σ)max < 0.001
1133 reflectionsΔρmax = 0.90 e Å3
107 parametersΔρmin = 0.81 e Å3
3 restraintsExtinction correction: SHELXTL (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.0094 (17)
Crystal data top
[Co4(C2O4)(PO4)2(H2O)2]V = 525.2 (2) Å3
Mr = 549.72Z = 2
Monoclinic, P21/nMo Kα radiation
a = 7.8541 (17) ŵ = 6.60 mm1
b = 4.7829 (10) ÅT = 293 K
c = 14.057 (3) Å0.32 × 0.20 × 0.10 mm
β = 95.937 (4)°
Data collection top
Bruker SMART APEX CCD area-detector
diffractometer
1133 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2000)
913 reflections with I > 2σ(I)
Tmin = 0.22, Tmax = 0.52Rint = 0.034
2798 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0403 restraints
wR(F2) = 0.094All H-atom parameters refined
S = 1.09Δρmax = 0.90 e Å3
1133 reflectionsΔρmin = 0.81 e Å3
107 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
Co10.40849 (8)0.46997 (13)0.80563 (5)0.0130 (2)
Co20.70451 (8)0.47453 (13)0.63392 (5)0.0122 (2)
P10.50343 (17)0.0223 (3)0.69630 (10)0.0139 (3)
O10.5074 (4)0.2997 (7)0.6975 (2)0.0126 (7)
O20.5646 (4)0.1346 (7)0.6038 (2)0.0155 (7)
O30.6187 (4)0.1571 (8)0.7802 (2)0.0158 (7)
O40.3244 (4)0.1379 (7)0.7118 (2)0.0148 (7)
C10.5588 (6)0.6255 (11)0.9925 (4)0.0171 (10)
O50.5694 (4)0.7013 (8)0.9079 (2)0.0183 (8)
O60.6373 (4)0.7274 (7)1.0660 (2)0.0134 (7)
O70.7066 (4)0.6605 (9)0.5068 (2)0.0197 (8)
H20.782 (4)0.584 (4)0.478 (3)0.030*
H10.733 (4)0.830 (4)0.512 (3)0.030*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Co10.0123 (4)0.0124 (4)0.0136 (4)0.0042 (2)0.0026 (3)0.0010 (2)
Co20.0129 (4)0.0118 (4)0.0109 (4)0.0044 (2)0.0034 (3)0.0011 (2)
P10.0132 (6)0.0138 (6)0.0146 (7)0.0006 (4)0.0005 (5)0.0003 (4)
O10.0105 (15)0.0154 (17)0.0116 (17)0.0009 (13)0.0003 (13)0.0001 (13)
O20.0181 (17)0.0162 (18)0.0126 (18)0.0010 (13)0.0039 (13)0.0023 (13)
O30.0123 (16)0.0203 (18)0.0143 (18)0.0014 (13)0.0008 (14)0.0047 (14)
O40.0136 (16)0.0171 (17)0.0136 (16)0.0010 (13)0.0001 (12)0.0011 (14)
C10.019 (2)0.022 (3)0.012 (2)0.003 (2)0.0089 (19)0.0024 (19)
O50.0235 (19)0.0231 (19)0.0074 (17)0.0043 (14)0.0018 (14)0.0004 (14)
O60.0164 (17)0.0176 (17)0.0054 (16)0.0056 (13)0.0033 (12)0.0010 (12)
O70.0190 (19)0.028 (2)0.0119 (19)0.0034 (15)0.0019 (14)0.0053 (15)
Geometric parameters (Å, º) top
Co1—O4i1.989 (3)P1—O41.547 (3)
Co1—O1ii2.090 (3)P1—O31.551 (3)
Co1—O6iii2.101 (3)O1—Co1vi2.090 (3)
Co1—O52.124 (4)O1—Co2vi2.156 (3)
Co1—O42.126 (4)O3—Co2v1.950 (3)
Co1—O32.284 (3)O4—Co1vii1.989 (3)
Co2—O3iv1.950 (3)C1—O61.246 (6)
Co2—O21.983 (4)C1—O51.254 (6)
Co2—O71.997 (4)C1—C1iii1.542 (10)
Co2—O1ii2.156 (3)O5—Co2iv2.329 (4)
Co2—O5v2.329 (4)O6—Co1iii2.101 (3)
P1—O21.530 (4)O7—H20.84 (2)
P1—O11.541 (4)O7—H10.84 (2)
O4i—Co1—O1ii95.97 (14)O2—P1—O4111.3 (2)
O4i—Co1—O6iii92.87 (14)O1—P1—O4111.9 (2)
O1ii—Co1—O6iii166.14 (13)O2—P1—O3106.9 (2)
O4i—Co1—O5110.36 (15)O1—P1—O3113.4 (2)
O1ii—Co1—O588.72 (13)O4—P1—O3102.26 (19)
O6iii—Co1—O578.19 (13)P1—O1—Co1vi121.8 (2)
O4i—Co1—O490.16 (9)P1—O1—Co2vi120.69 (19)
O1ii—Co1—O493.29 (13)Co1vi—O1—Co2vi111.99 (15)
O6iii—Co1—O497.35 (14)P1—O2—Co2108.8 (2)
O5—Co1—O4159.08 (14)P1—O3—Co2v127.4 (2)
O4i—Co1—O3156.31 (14)P1—O3—Co190.96 (15)
O1ii—Co1—O384.41 (13)Co2v—O3—Co1132.59 (17)
O6iii—Co1—O391.76 (13)P1—O4—Co1vii132.5 (2)
O5—Co1—O393.33 (13)P1—O4—Co197.21 (17)
O4—Co1—O366.20 (12)Co1vii—O4—Co1126.90 (16)
O3iv—Co2—O2147.43 (15)O6—C1—O5126.7 (4)
O3iv—Co2—O7106.46 (15)O6—C1—C1iii116.3 (5)
O2—Co2—O7103.26 (16)O5—C1—C1iii117.0 (6)
O3iv—Co2—O1ii90.85 (14)C1—O5—Co1113.4 (3)
O2—Co2—O1ii95.36 (13)C1—O5—Co2iv121.9 (3)
O7—Co2—O1ii102.74 (14)Co1—O5—Co2iv122.52 (15)
O3iv—Co2—O5v83.95 (13)C1—O6—Co1iii115.0 (3)
O2—Co2—O5v84.61 (13)Co2—O7—H2108 (2)
O7—Co2—O5v86.98 (14)Co2—O7—H1113 (5)
O1ii—Co2—O5v169.97 (13)H2—O7—H1107 (3)
O2—P1—O1110.7 (2)
O2—P1—O1—Co1vi173.41 (19)O3—P1—O4—Co1vii142.9 (3)
O4—P1—O1—Co1vi48.6 (3)O2—P1—O4—Co197.2 (2)
O3—P1—O1—Co1vi66.5 (3)O1—P1—O4—Co1138.41 (17)
O2—P1—O1—Co2vi35.0 (3)O3—P1—O4—Co116.7 (2)
O4—P1—O1—Co2vi159.81 (19)O4i—Co1—O4—P1166.4 (2)
O3—P1—O1—Co2vi85.1 (3)O1ii—Co1—O4—P170.39 (18)
O1—P1—O2—Co2141.52 (19)O6iii—Co1—O4—P1100.71 (18)
O4—P1—O2—Co293.3 (2)O5—Co1—O4—P124.6 (5)
O3—P1—O2—Co217.6 (2)O3—Co1—O4—P112.03 (15)
O3iv—Co2—O2—P142.8 (4)O4i—Co1—O4—Co1vii32.3 (2)
O7—Co2—O2—P1161.77 (19)O1ii—Co1—O4—Co1vii128.3 (2)
O1ii—Co2—O2—P157.3 (2)O6iii—Co1—O4—Co1vii60.6 (2)
O5v—Co2—O2—P1112.6 (2)O5—Co1—O4—Co1vii136.7 (3)
O2—P1—O3—Co2v108.5 (3)O3—Co1—O4—Co1vii149.3 (3)
O1—P1—O3—Co2v13.8 (3)O6—C1—O5—Co1179.2 (4)
O4—P1—O3—Co2v134.4 (2)C1iii—C1—O5—Co12.9 (7)
O2—P1—O3—Co1101.70 (17)O6—C1—O5—Co2iv17.1 (7)
O1—P1—O3—Co1136.07 (17)C1iii—C1—O5—Co2iv160.8 (4)
O4—P1—O3—Co115.39 (19)O4i—Co1—O5—C186.3 (4)
O4i—Co1—O3—P17.9 (4)O1ii—Co1—O5—C1177.8 (4)
O1ii—Co1—O3—P184.19 (17)O6iii—Co1—O5—C12.4 (3)
O6iii—Co1—O3—P1109.16 (17)O4—Co1—O5—C182.0 (5)
O5—Co1—O3—P1172.57 (17)O3—Co1—O5—C193.5 (4)
O4—Co1—O3—P111.90 (15)O4i—Co1—O5—Co2iv110.0 (2)
O4i—Co1—O3—Co2v139.2 (3)O1ii—Co1—O5—Co2iv14.1 (2)
O1ii—Co1—O3—Co2v128.6 (2)O6iii—Co1—O5—Co2iv161.3 (2)
O6iii—Co1—O3—Co2v38.0 (2)O4—Co1—O5—Co2iv81.7 (4)
O5—Co1—O3—Co2v40.3 (2)O3—Co1—O5—Co2iv70.2 (2)
O4—Co1—O3—Co2v135.3 (3)O5—C1—O6—Co1iii177.6 (4)
O2—P1—O4—Co1vii103.2 (3)C1iii—C1—O6—Co1iii0.3 (7)
O1—P1—O4—Co1vii21.2 (4)
Symmetry codes: (i) x+1/2, y+1/2, z+3/2; (ii) x, y+1, z; (iii) x+1, y+1, z+2; (iv) x+3/2, y+1/2, z+3/2; (v) x+3/2, y1/2, z+3/2; (vi) x, y1, z; (vii) x+1/2, y1/2, z+3/2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O7—H2···O6v0.84 (2)1.94 (3)2.665 (5)144 (5)
O7—H1···O6iv0.84 (2)2.46 (4)3.188 (5)145 (5)
Symmetry codes: (iv) x+3/2, y+1/2, z+3/2; (v) x+3/2, y1/2, z+3/2.

Experimental details

Crystal data
Chemical formula[Co4(C2O4)(PO4)2(H2O)2]
Mr549.72
Crystal system, space groupMonoclinic, P21/n
Temperature (K)293
a, b, c (Å)7.8541 (17), 4.7829 (10), 14.057 (3)
β (°) 95.937 (4)
V3)525.2 (2)
Z2
Radiation typeMo Kα
µ (mm1)6.60
Crystal size (mm)0.32 × 0.20 × 0.10
Data collection
DiffractometerBruker SMART APEX CCD area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2000)
Tmin, Tmax0.22, 0.52
No. of measured, independent and
observed [I > 2σ(I)] reflections
2798, 1133, 913
Rint0.034
(sin θ/λ)max1)0.639
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.040, 0.094, 1.09
No. of reflections1133
No. of parameters107
No. of restraints3
H-atom treatmentAll H-atom parameters refined
Δρmax, Δρmin (e Å3)0.90, 0.81

Computer programs: SMART (Bruker, 2000), SAINT-Plus (Bruker, 2000), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O7—H2···O6i0.84 (2)1.94 (3)2.665 (5)144 (5)
O7—H1···O6ii0.84 (2)2.46 (4)3.188 (5)145 (5)
Symmetry codes: (i) x+3/2, y1/2, z+3/2; (ii) x+3/2, y+1/2, z+3/2.
 

Acknowledgements

The authors thank the Center of Testing and Analysis, Nanjing University, for support.

References

First citationBruker (2000). SADABS (Version 2.03), SAINT-Plus (Version 6) and SMART (Version 5.0). Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
First citationChoudhury, A. & Natarajan, S. (2000). Solid State Sci. 2, 365–372.  Web of Science CSD CrossRef CAS Google Scholar
First citationDesiraju, G. R. & Steiner, T. (1999). The Weak Hydrogen Bond, p. 13. New York: Oxford University Press Inc.  Google Scholar
First citationLethbridge, Z. A. D., Smith, M. J., Tiwary, S. K., Harrison, A. & Lightfoot, P. (2004). Inorg. Chem. 43, 11–13.  Web of Science CSD CrossRef PubMed CAS Google Scholar
First citationSheldrick, G. M. (2008). Acta Cryst. A64, 112–122.  Web of Science CrossRef CAS IUCr Journals Google Scholar

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