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Acta Crystallogr Sect E Struct Rep Online. 2009 March 1; 65(Pt 3): m341–m342.
Published online 2009 February 28. doi:  10.1107/S1600536809006771
PMCID: PMC2968619

Tetra­aqua­bis(nicotinamide-κN 1)cobalt(II) bis­(2-fluoro­benzoate)

Abstract

The title complex, [Co(C6H6N2O)2(H2O)4](C7H4FO2)2, contains one Co(II) atom (site symmetry An external file that holds a picture, illustration, etc.
Object name is e-65-0m341-efi1.jpg), two monodentate nicotin­amide (NA) ligands, four coordinated water mol­ecules and two 2-fluoro­benzoate (FB) anions. The four O atoms in the equatorial plane around the Co atom form a slightly distorted square-planar arrangement, while the slightly distorted octa­hedral coordination is completed by the two N atoms of the NA ligands in the axial positions. The dihedral angle between the carboxyl group and the adjacent benzene ring is 29.8 (3)°, while the pyridine and benzene rings are oriented at a dihedral angle of 7.97 (12)°. In the crystal structure, mol­ecules are linked by O—H(...)O, N—H(...)O and N—H(...)F hydrogen bonds, forming an infinite three-dimensional network. π–π Contacts between the pyridine and benzene rings [centroid–centroid distance = 3.673 (3) Å] may further stabilize the crystal structure.

Related literature

For general background, see: Antolini et al. (1982 [triangle]); Krishnamachari (1974 [triangle]); Nadzhafov et al. (1981 [triangle]). For related structures, see: Hökelek & Necefoğlu (1996 [triangle], 1998 [triangle]); Hökelek et al. (1997 [triangle], 2007 [triangle]); Necefoğlu et al. (2002 [triangle]); Tercan et al. (2009 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-65-0m341-scheme1.jpg

Experimental

Crystal data

  • [Co(C6H6N2O)2(H2O)4](C7H4FO2)2
  • M r = 653.45
  • Triclinic, An external file that holds a picture, illustration, etc.
Object name is e-65-0m341-efi2.jpg
  • a = 7.2913 (2) Å
  • b = 7.4522 (4) Å
  • c = 14.4853 (5) Å
  • α = 82.160 (2)°
  • β = 77.275 (3)°
  • γ = 63.740 (3)°
  • V = 687.83 (5) Å3
  • Z = 1
  • Mo Kα radiation
  • μ = 0.70 mm−1
  • T = 294 K
  • 0.35 × 0.25 × 0.20 mm

Data collection

  • Rigaku R-AXIS RAPID-S diffractometer
  • Absorption correction: multi-scan (Blessing, 1995 [triangle]) T min = 0.807, T max = 0.865
  • 14875 measured reflections
  • 2817 independent reflections
  • 2679 reflections with I > 2σ(I)
  • R int = 0.044

Refinement

  • R[F 2 > 2σ(F 2)] = 0.042
  • wR(F 2) = 0.122
  • S = 1.08
  • 2817 reflections
  • 220 parameters
  • 10 restraints
  • H atoms treated by a mixture of independent and constrained refinement
  • Δρmax = 1.37 e Å−3
  • Δρmin = −0.42 e Å−3

Data collection: CrystalClear (Rigaku/MSC, 2005 [triangle]); cell refinement: CrystalClear; data reduction: CrystalClear; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: Mercury (Macrae et al., 2006 [triangle]); software used to prepare material for publication: WinGX (Farrugia, 1999 [triangle]).

Table 1
Selected geometric parameters (Å, °)
Table 2
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536809006771/xu2482sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809006771/xu2482Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Acknowledgments

The authors are indebted to the Department of Chemistry, Atatürk University, Erzurum, Turkey, for the use of X-ray diffractometer purchased under grant No. 2003/219 of the University Research Fund.

supplementary crystallographic information

Comment

Transition metal complexes with biochemically active ligands frequently show interesting physical and/or chemical properties, through which they may find applications in biological systems (Antolini et al., 1982). The structural functions and coordination relationships of the arylcarboxylate ion in transition metal complexes of benzoic acid derivatives may be changed, depending on the nature and position of the substituted groups on the benzene ring, the nature of the additional ligand molecule or solvent, and the medium of the synthesis (Nadzhafov et al., 1981). Nicotinamide (NA) is one form of niacin and a deficiency of this vitamin leads to loss of copper from the body, known as pellagra disease. Victims of pellagra show unusually high serum and urinary copper levels (Krishnamachari, 1974). The structure determination of the title compound, (I), a cobalt complex with two nicotinamide (NA) ligands, four water molecules and two 2-fluorobenzoate (FB) anions, was undertaken in order to determine the properties of the NA ligands and FB anions and also to compare the results obtained with those reported previously.

Compound (I) is a monomeric complex, with the Co atom on a centre of symmetry. It contains two NA ligands, four water molecules and two FB molecules (Fig. 1). The NA ligands are monodentate. The four O atoms (O4, O5, and the symmetry-related atoms, O4', O5') in the equatorial plane around the Co atom form a slightly distorted square-planar arrangement, while the slightly distorted octahedral coordination is completed by the two N atoms of the NA ligands (N1, N1') in the axial positions (Table 1 and Fig. 1). The intramolecular O—H···O hydrogen bonds (Table 2) link two of the water molecules to the two FB anions.

The near equality of the C7—O2 [1.244 (4) Å] and C7—O3 [1.270 (4) Å] bonds in the carboxylate group indicates a delocalized bonding arrangement, rather than localized single and double bonds, and may be compared with the corresponding distances: 1.279 (4) and 1.246 (4) Å in bis(µ-4-hydroxybenzoato-O:O')bis- [(N,N-diethylnicotinamide-N1)-(4-hydroxybenzoato-O)zinc(II)] dihydrate (Hökelek & Necefouglu, 1996), 1.267 (3) and 1.237 (4) Å in trans-diaquabis- (N,N-diethylnicotinamide-N1)bis(4-nitrobenzoato-O)copper(II) (Hökelek et al., 1997), 1.254 (2) and 1.251 (2) Å in trans-diaquabis(nicotinamide-N1)- bis(4-nitrobenzoato-O)cobalt(II) (Hökelek & Necefouglu, 1998), 1.240 (3), 1.281 (3) and 1.274 (3), 1.245 (3) Å in bis(4-hydroxybenzoato-κO)bis(nicotin amide-κN)zinc(II) (Necefoğlu et al., 2002), 1.260 (4) and 1.252 (4) Å in diaquabis(N,N'-diethylnicotinamide-κN)bis(4-fluorobenzoato-κO)zinc(II) (Hökelek et al., 2007) and 1.284 (2), 1.248 (2) and 1.278 (2), 1.241 (2) Å in bis[4-(methylamino)benzoato-κO]bis(nicotinamide-κN)zinc(II) (Tercan et al., 2009). This may be due to the intramolecular O—H···O hydrogen bonding of the carboxylate O atom (Table 2).

The dihedral angle between the planar carboxylate group (O2/C7/O3) and the adjacent benzene B (C8—C14) ring is 29.8 (3)°. The dihedral angle between the pyridine ring A (N1/C1—C5) and benzene ring B is 7.97 (12)°.

As can be seen from the packing diagram (Fig. 2), the molecules are linked by O—H···O, N—H···O and N—H···F hydrogen bonds (Table 2) to form an infinite three-dimensional network, in which they may be effective in the stabilization of the structure. The π-π contact between the pyridine and the benzene rings, Cg1—Cg2 [where Cg1 and Cg2 are centroids of the rings A (N1/C1—C5) and B (C8—C14), respectively] may further stabilize the structure, with centroid-centroid distance of 3.673 (3) Å.

Experimental

The title compound was prepared by the reaction of CoSO4.7(H2O) (1.40 g, 5 mmol) in H2O (20 ml) and NA (1.22 g, 10 mmol) in H2O (20 ml) with 2-fluorobenzoate (1.62 g, 10 mmol) in H2O (50 ml) at room temperature. The mixture was filtered and set aside to crystallize at ambient temperature for one week, giving pink single crystals.

Refinement

H atoms of water molecules and NH2 group were located in difference syntheses and refined isotropically [O—H = 0.90 (3)–0.91 (5) Å, Uiso(H) = 0.053 (12) -0.10 (2) Å2; N—H = 0.87 (2) Å, Uiso(H) = 0.047 (11) and 0.041 (10) Å2]. The remaining H atoms were positioned geometrically with C—H = 0.93 Å, for aromatic H atoms and constrained to ride on their parent atoms, with Uiso(H) = 1.2Ueq(C). The restrains on the N—H bonds and the H—N—H bond angles of the NH2 group and O—H bonds and H—O—H bond angles of water molecules were applied.

Figures

Fig. 1.
The molecular structure of the title molecule with the atom-numbering scheme. Displacement ellipsoids are drawn at the 40% probability level [symmetry code ('): -x, -y, -z]. Hydrogen bonds are shown as dotted lines.
Fig. 2.
A partial packing diagram of the title compound. Hydrogen bonds are shown as dotted lines. H atoms not involved in hydrogen bonding are omitted.

Crystal data

[Co(C6H6N2O)2(H2O)4](C7H4FO2)2Z = 1
Mr = 653.45F(000) = 337
Triclinic, P1Dx = 1.578 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 7.2913 (2) ÅCell parameters from 4045 reflections
b = 7.4522 (4) Åθ = 2.9–26.4°
c = 14.4853 (5) ŵ = 0.70 mm1
α = 82.160 (2)°T = 294 K
β = 77.275 (3)°Prism, pink
γ = 63.740 (3)°0.35 × 0.25 × 0.20 mm
V = 687.83 (5) Å3

Data collection

Rigaku R-AXIS RAPID-S diffractometer2817 independent reflections
Radiation source: fine-focus sealed tube2679 reflections with I > 2σ(I)
graphiteRint = 0.044
ω scansθmax = 26.4°, θmin = 2.9°
Absorption correction: multi-scan (Blessing, 1995)h = −9→9
Tmin = 0.807, Tmax = 0.865k = −8→9
14875 measured reflectionsl = −18→18

Refinement

Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.042Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.122H atoms treated by a mixture of independent and constrained refinement
S = 1.08w = 1/[σ2(Fo2) + (0.0649P)2 + 0.4285P] where P = (Fo2 + 2Fc2)/3
2817 reflections(Δ/σ)max < 0.001
220 parametersΔρmax = 1.37 e Å3
10 restraintsΔρmin = −0.42 e Å3

Special details

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)

xyzUiso*/Ueq
Co10.50000.50000.50000.0306 (2)
F10.6929 (4)0.9615 (4)0.85873 (18)0.0632 (7)
O10.2777 (4)0.4281 (5)0.97121 (18)0.0544 (7)
O20.9068 (4)0.8007 (4)0.68460 (17)0.0433 (6)
O30.7033 (4)0.9537 (4)0.57755 (17)0.0414 (6)
O40.6387 (4)0.7065 (4)0.46282 (17)0.0398 (6)
H410.695 (6)0.741 (6)0.504 (3)0.057 (13)*
H420.529 (7)0.818 (6)0.449 (4)0.10 (2)*
O50.7856 (4)0.2570 (4)0.46679 (18)0.0450 (6)
H510.896 (5)0.227 (7)0.419 (3)0.070 (15)*
H520.799 (7)0.140 (5)0.499 (3)0.053 (12)*
N10.5506 (4)0.4540 (4)0.64340 (18)0.0334 (6)
N20.0471 (5)0.5743 (5)0.8720 (2)0.0460 (8)
H21−0.056 (5)0.588 (6)0.918 (2)0.047 (11)*
H220.019 (6)0.640 (5)0.819 (2)0.041 (10)*
C10.3949 (5)0.4742 (5)0.7168 (2)0.0337 (7)
H10.26790.49260.70420.040*
C20.4139 (5)0.4691 (5)0.8104 (2)0.0348 (7)
C30.6044 (6)0.4392 (5)0.8293 (2)0.0393 (8)
H30.62290.43400.89130.047*
C40.7650 (5)0.4175 (5)0.7546 (3)0.0408 (8)
H40.89370.39810.76540.049*
C50.7332 (5)0.4248 (5)0.6634 (2)0.0380 (7)
H50.84340.40890.61350.046*
C60.2384 (6)0.4906 (6)0.8914 (2)0.0393 (8)
C70.7326 (5)0.8934 (5)0.6617 (2)0.0326 (7)
C80.5407 (5)0.9340 (5)0.7363 (2)0.0330 (7)
C90.3610 (5)0.9450 (5)0.7114 (3)0.0381 (7)
H90.36130.93040.64860.046*
C100.1833 (6)0.9768 (6)0.7779 (3)0.0474 (9)
H100.06630.98130.76010.057*
C110.1798 (7)1.0021 (7)0.8708 (3)0.0572 (11)
H110.05931.02610.91550.069*
C120.3539 (7)0.9920 (7)0.8980 (3)0.0544 (10)
H120.35261.00700.96090.065*
C130.5296 (6)0.9593 (6)0.8305 (2)0.0411 (8)

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
Co10.0292 (3)0.0361 (4)0.0231 (3)−0.0124 (3)−0.0019 (2)−0.0010 (2)
F10.0543 (14)0.0868 (19)0.0507 (14)−0.0276 (14)−0.0144 (11)−0.0109 (13)
O10.0510 (16)0.084 (2)0.0263 (13)−0.0306 (15)−0.0069 (11)0.0080 (13)
O20.0319 (12)0.0595 (16)0.0341 (13)−0.0166 (11)−0.0066 (10)0.0025 (11)
O30.0418 (13)0.0504 (14)0.0300 (12)−0.0196 (11)−0.0077 (10)0.0065 (10)
O40.0449 (14)0.0440 (14)0.0350 (13)−0.0226 (12)−0.0102 (11)0.0017 (10)
O50.0385 (14)0.0435 (14)0.0371 (14)−0.0100 (11)0.0063 (11)0.0005 (11)
N10.0340 (14)0.0389 (15)0.0252 (13)−0.0145 (12)−0.0041 (10)−0.0003 (11)
N20.0397 (17)0.063 (2)0.0298 (16)−0.0209 (15)−0.0032 (13)0.0059 (14)
C10.0331 (16)0.0400 (17)0.0272 (15)−0.0151 (14)−0.0060 (12)−0.0001 (13)
C20.0388 (17)0.0374 (17)0.0269 (15)−0.0161 (14)−0.0057 (13)0.0014 (13)
C30.0453 (19)0.0452 (19)0.0297 (16)−0.0196 (16)−0.0137 (14)0.0028 (14)
C40.0348 (17)0.047 (2)0.0424 (19)−0.0175 (15)−0.0128 (14)0.0020 (15)
C50.0325 (16)0.0429 (18)0.0353 (17)−0.0147 (14)−0.0032 (13)−0.0005 (14)
C60.048 (2)0.048 (2)0.0246 (16)−0.0241 (17)−0.0045 (14)0.0009 (14)
C70.0362 (17)0.0342 (16)0.0306 (16)−0.0177 (14)−0.0068 (13)−0.0004 (12)
C80.0335 (16)0.0317 (16)0.0322 (16)−0.0137 (13)−0.0052 (13)0.0012 (12)
C90.0386 (18)0.0392 (18)0.0396 (18)−0.0188 (15)−0.0092 (14)0.0000 (14)
C100.0323 (18)0.050 (2)0.060 (2)−0.0193 (16)−0.0063 (16)0.0021 (18)
C110.042 (2)0.068 (3)0.052 (2)−0.022 (2)0.0101 (18)−0.008 (2)
C120.051 (2)0.070 (3)0.035 (2)−0.022 (2)0.0032 (17)−0.0094 (18)
C130.0383 (18)0.047 (2)0.0354 (18)−0.0158 (16)−0.0067 (14)−0.0024 (15)

Geometric parameters (Å, °)

Co1—O4i2.143 (3)C2—C11.387 (4)
Co1—O42.143 (3)C2—C31.390 (5)
Co1—O5i2.075 (3)C3—H30.9300
Co1—O52.075 (3)C4—C31.375 (5)
Co1—N12.145 (3)C4—H40.9300
Co1—N1i2.145 (3)C5—C41.381 (5)
F1—C131.348 (4)C5—H50.9300
O1—C61.232 (4)C6—C21.499 (5)
O2—C71.244 (4)C7—C81.505 (5)
O3—C71.270 (4)C8—C91.399 (5)
O4—H410.91 (5)C8—C131.384 (5)
O4—H420.90 (3)C9—C101.379 (5)
O5—H510.90 (4)C9—H90.9300
O5—H520.91 (2)C10—H100.9300
N1—C11.342 (4)C11—C101.377 (6)
N1—C51.342 (4)C11—H110.9300
N2—C61.330 (5)C12—C111.378 (6)
N2—H210.87 (2)C12—C131.376 (5)
N2—H220.87 (2)C12—H120.9300
C1—H10.9300
O4i—Co1—O4180.0C2—C3—H3120.6
O4i—Co1—N186.31 (10)C4—C3—C2118.7 (3)
O4—Co1—N193.69 (10)C4—C3—H3120.6
O4i—Co1—N1i93.69 (10)C3—C4—C5119.3 (3)
O4—Co1—N1i86.31 (10)C3—C4—H4120.3
O5i—Co1—O4i91.75 (12)C5—C4—H4120.3
O5—Co1—O4i88.25 (12)N1—C5—C4123.0 (3)
O5i—Co1—O488.25 (12)N1—C5—H5118.5
O5—Co1—O491.75 (12)C4—C5—H5118.5
O5i—Co1—O5180.0O1—C6—N2123.5 (3)
O5i—Co1—N192.59 (11)O1—C6—C2119.1 (3)
O5—Co1—N187.41 (11)N2—C6—C2117.3 (3)
O5i—Co1—N1i87.41 (11)O2—C7—O3124.3 (3)
O5—Co1—N1i92.59 (11)O2—C7—C8119.3 (3)
N1—Co1—N1i180.000 (1)O3—C7—C8116.3 (3)
Co1—O4—H41124 (3)C9—C8—C7119.6 (3)
Co1—O4—H42101 (4)C13—C8—C7123.9 (3)
H41—O4—H42106 (3)C13—C8—C9116.5 (3)
Co1—O5—H51136 (3)C8—C9—H9119.2
Co1—O5—H52116 (3)C10—C9—C8121.5 (3)
H51—O5—H52107 (3)C10—C9—H9119.2
C1—N1—Co1121.3 (2)C9—C10—H10120.1
C5—N1—C1117.3 (3)C11—C10—C9119.7 (4)
C5—N1—Co1121.1 (2)C11—C10—H10120.1
C6—N2—H21118 (3)C10—C11—C12120.4 (4)
C6—N2—H22122 (3)C10—C11—H11119.8
H21—N2—H22118 (4)C12—C11—H11119.8
N1—C1—C2123.3 (3)C11—C12—H12120.6
N1—C1—H1118.3C13—C12—C11118.8 (4)
C2—C1—H1118.3C13—C12—H12120.6
C1—C2—C3118.4 (3)F1—C13—C12117.1 (3)
C1—C2—C6122.5 (3)F1—C13—C8119.8 (3)
C3—C2—C6119.1 (3)C12—C13—C8123.0 (4)
O4i—Co1—N1—C1−51.9 (3)O1—C6—C2—C3−19.9 (5)
O4—Co1—N1—C1128.1 (3)N2—C6—C2—C1−20.0 (5)
O4i—Co1—N1—C5135.3 (3)N2—C6—C2—C3161.2 (3)
O4—Co1—N1—C5−44.7 (3)O2—C7—C8—C9−149.0 (3)
O5i—Co1—N1—C139.7 (3)O2—C7—C8—C1330.0 (5)
O5—Co1—N1—C1−140.3 (3)O3—C7—C8—C929.2 (4)
O5i—Co1—N1—C5−133.1 (3)O3—C7—C8—C13−151.7 (3)
O5—Co1—N1—C546.9 (3)C7—C8—C9—C10178.3 (3)
Co1—N1—C1—C2−172.2 (3)C13—C8—C9—C10−0.8 (5)
C5—N1—C1—C20.9 (5)C7—C8—C13—F14.5 (5)
Co1—N1—C5—C4172.4 (3)C7—C8—C13—C12−178.5 (4)
C1—N1—C5—C4−0.8 (5)C9—C8—C13—F1−176.4 (3)
C3—C2—C1—N1−0.8 (5)C9—C8—C13—C120.5 (6)
C6—C2—C1—N1−179.5 (3)C8—C9—C10—C111.1 (6)
C1—C2—C3—C40.5 (5)C12—C11—C10—C9−1.2 (7)
C6—C2—C3—C4179.3 (3)C11—C12—C13—F1176.4 (4)
C5—C4—C3—C2−0.4 (5)C11—C12—C13—C8−0.6 (7)
N1—C5—C4—C30.5 (6)C13—C12—C11—C101.0 (7)
O1—C6—C2—C1158.9 (4)

Symmetry codes: (i) −x+1, −y+1, −z+1.

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
N2—H21···O1ii0.87 (2)2.04 (3)2.902 (5)171 (4)
N2—H22···F1iii0.87 (2)2.54 (4)2.916 (5)107 (2)
N2—H22···O2iii0.87 (2)2.26 (3)3.116 (5)172 (4)
O4—H41···O30.91 (5)2.06 (4)2.885 (4)151 (4)
O4—H42···O3iv0.90 (3)1.86 (5)2.761 (4)178 (5)
O5—H51···O2v0.90 (4)1.80 (4)2.695 (4)172 (4)
O5—H52···O3vi0.91 (2)1.95 (4)2.798 (4)156 (4)

Symmetry codes: (ii) −x, −y+1, −z+2; (iii) x−1, y, z; (iv) −x+1, −y+2, −z+1; (v) −x+2, −y+1, −z+1; (vi) x, y−1, z.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: XU2482).

References

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