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Acta Crystallogr Sect E Struct Rep Online. 2009 August 1; 65(Pt 8): m930–m931.
Published online 2009 July 18. doi:  10.1107/S1600536809026944
PMCID: PMC2977141

Bis(creatininium) tetra­chlorido­cadmate(II)

Abstract

In the title compound, (C4H8N3O)2[CdCl4], the asymmetric unit comprises two creatininium cations and one tetra­chloridocadmate anion. Cd(...)O secondary bonding links one of the two imidazole rings and the anion into ion pairs. The free and bound cations form layers between which the [CdCl4]2− anions are sandwiched. The CdII atom adopts a distorted trigonal-bipyramidal geometry in which the Cd(...)O bond is axial. Inter­molecular N—H(...)Cl hydrogen bonds form a two-dimensional network parallel to (001) which ensures the junction between creatininium cations and [CdCl4]2− anions.

Related literature

An abnormal level of creatinine in biological fluids is an indicator of various medical conditions, see: Narayanan & Appleton (1980 [triangle]). For inter­actions between creatinine and biologically important metal ions, see: Canty et al. (1979 [triangle]). Different complex species are formed depending on the reaction conditions, see: Nishida & Kida (1985 [triangle]). For bond lengths in the neutral creatinine mol­ecule, see: Smith & White (2001 [triangle]) and in creatinium compounds, see: Wilkinson & Harrison (2005 [triangle]). For Cd—Cl bond distances in dichlorido­bis(creatinine)cadmium(II), see: Okabe et al. (1995 [triangle]). For Cl—Cd—Cl bond angles in bis­(2,3,5-triphenyl­tetra­zolium)tetra­chloridocadmate(II), see: Zhang et al. (2007 [triangle]). For hydrogen-bond motifs, see: Bernstein et al. (1995 [triangle]); Etter et al. (1990 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-65-0m930-scheme1.jpg

Experimental

Crystal data

  • (C4H8N3O)2[CdCl4]
  • M r = 482.48
  • Triclinic, An external file that holds a picture, illustration, etc.
Object name is e-65-0m930-efi5.jpg
  • a = 7.5203 (4) Å
  • b = 7.6761 (3) Å
  • c = 15.0757 (7) Å
  • α = 79.476 (2)°
  • β = 85.438 (5)°
  • γ = 83.214 (3)°
  • V = 848.14 (7) Å3
  • Z = 2
  • Mo Kα radiation
  • μ = 1.93 mm−1
  • T = 100 K
  • 0.25 × 0.15 × 0.1 mm

Data collection

  • Nonius KappaCCD diffractometer
  • Absorption correction: multi-scan (SADABS; Sheldrick,1996 [triangle]) T min = 0.644, T max = 0.831
  • 10950 measured reflections
  • 3843 independent reflections
  • 3711 reflections with I > 2σ(I)
  • R int = 0.064

Refinement

  • R[F 2 > 2σ(F 2)] = 0.019
  • wR(F 2) = 0.048
  • S = 1.11
  • 3843 reflections
  • 216 parameters
  • H atoms treated by a mixture of independent and constrained refinement
  • Δρmax = 0.77 e Å−3
  • Δρmin = −0.54 e Å−3

Data collection: COLLECT (Nonius, 2002 [triangle]); cell refinement: DENZO and SCALEPACK (Otwinowski & Minor, 1997 [triangle]); data reduction: DENZO and SCALEPACK; program(s) used to solve structure: SIR92 (Altomare et al., 1993 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: ORTEP-3 (Farrugia, 1997 [triangle]) and Mercury (Macrae et al., 2006 [triangle]); software used to prepare material for publication: WinGX (Farrugia, 1999 [triangle]) and PARST (Nardelli, 1995 [triangle]).

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

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809026944/bt2978sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809026944/bt2978Isup2.hkl

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

Acknowledgments

This work was supported by the Université 20 Aout 1955 Skikda. Algéria. We would like to thank Thierry Roisnel from Renne 1 University for collecting the data and Olivier Mentré from UCCS, Equipe de Chimie du Solide, UMR CNRS 8181, ENSC Lille. France for his useful help.

supplementary crystallographic information

Comment

Creatinine (2-amino- 1,5-dihydro- 1-methyl-4H-imidazol-4-one) is the waste product of protein metabolism that is found in the urine. It can be measured to assess overall kidney function. An abnormal level of creatinine in biological fluids is an indicator of various malady states (Narayanan & Appleton, 1980).

Over the last decade, there have been an increasing number of reports on compounds resulting from the combination of creatinine and biologically important metal ions, in order to obtain structural information on the mode of interaction between them. (Canty et al., 1979), however, the different complex species are formed depending on the reaction conditions (Nishida & Kida, 1985). In the title compound, (I), we determine the crystal structure of a new cadmium complex showing the metal coordination and the structure cohesion. It is the first example of salt containing creatininium cation and (CdCl4)2- anion.

The asymmetric unit, shown in Fig. 1, consists of the tetrachlorocadmate anion and two cations of creatinine protonated. Hence, the complex investigated is better formulated as: 2(C4H8ON3)+,(CdC14)2-.

The cadmium is coordinated to four Cl atoms and one O atom forming a distorted trigonal bipyramid CdX4O. As can be seen in Table 1, three of the four Cd1—Cl bond distances (2.4571 (5), 2.4596 (4) and 2.4627 (4) Å) are similar to those found in the dichlorobis(creatinine)cadmium(II) (Okabe et al., 1995) and significantly shorter than the axial Cd···Cl3 distance (2.5678 (4) Å) witch is in trans position to the O atom (dCd1—O = 2.6854 (13) Å and 0.1 Å longer than the other chlorine atoms. In the trigonal bipyramid CdCl4O, the displacement of Cd towards Cl3 from the equatorial plane defined by Cl1; Cl2 and Cl4 atoms is 0.2574 (2) Å. Furthermore, the Cl—Cd—Cl bond angles in the title complex fall in the range 96.649 (15) ° -120.122 (17) ° which is very different to those of the free anionic CdCl4 moiety of bis(2,3,5-triphenyltetrazolium) tetrachloridocadmate(II) (Zhang et al., 2007) where the Cl—Cd—Cl bond angles lie in the range 107.18 (3) ° - 117.232 (16) °.

As expected, creatininium cations are approximately planar. In the bound cation, the r.m.s. deviation for the non-H atoms = 0.0311 Å, the maximum deviation of N5 from the mean plane is 0.0592 (15) Å. However, the free cation has a r.m.s deviation for non-H atoms = 0.0488 Å with a maximum deviation from the mean plane = 0.0851 (0.11) Å (for O2).

In table 1, we notice that in each creatininium cation, the three C—N bond distances are clearly different, with C6—N4 and C3—N1 much longer than the other ones. This results in the localization of the exocyclic C3—N2 [1.325 (2) Å] & C3—N3 [1.321 (2) Å] and C6—N5 [1.319 (2) Å] & C6—N6 [1.322 (2) Å] double bonds in the free and bound creatininium respectively and the adjacent single bonds C3—N1 [1.371 (2) Å] and C6—N4 [1.380 (2) Å]. These values somewhat compared with the intermediate, delocalized values in the parent neutral creatinine molecule [1.320 (3) and 1.349 (3) Å], respectively (Smith & White, 2001). Such difference in C—N bonds has been reported in some creatinium compounds (Wilkinson et al., 2005).

In the crystal structure of (I), the anionic and cationic components are linked by N—H···Cl, hydrogen bonds into a continuous two-dimensional network (Table 3). In which alternating R22(8), R24(12) and R66(28) (Bernstein, et al.,1995) hydrogen-bonded rings are formed. Fig. 2 also shows a strong intramolecular hydrogen bond (N4—H4···Cl4) which can be described with an S(6) graph set motif. These rings form layers joined by means of the N6—H6···Cl2 hydrogen bond. In terms of graph-set analysis (Etter et al., 1990; Bernstein et al., 1995), the descriptor for this pattern is R44(12) ring (Fig. 3).

Experimental

The title compound was crystallized from a supersaturated hydrochloric acid solution (45%, 5 ml) prepared using doubly distilled water and a mixture of cadmium(II) chloride (1.83 g) and creatinine (2.26 g). Colourless plates-shaped single crystals of (I) were obtained at ambient temperature by slow evaporation of the solution.

Refinement

The iminium and ammino H atoms were located in a difference Fourier map and was refined isotropically. The methyl H atoms were constrained to an ideal geometry (C—H = 0.96 Å) with Uiso(H) = 1.2Ueq(C), but were allowed to rotate freely about the C—C bonds. The methylene H atoms were placed in geometrically idealized positions (C—H = 0.97 Å) and constrained to ride on their parent atoms with Uiso(H) = 1.2Ueq(C).

Figures

Fig. 1.
The independent components of (I), showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 50% probability level.
Fig. 2.
Part of the crystal structure of (I), showing the formation of the R22(8), R24(12) and R66(28) rings. Hydrogen bonds are shown as dashed lines. Hydrogen atoms not involved in the motif have been omitted for clarity.
Fig. 3.
Part of the crystal structure of (I), showing the R44(12) ring set motif

Crystal data

(C4H8N3O)2[CdCl4]Z = 2
Mr = 482.48F(000) = 476
Triclinic, P1Dx = 1.889 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 7.5203 (4) ÅCell parameters from 8132 reflections
b = 7.6761 (3) Åθ = 2.7–27.4°
c = 15.0757 (7) ŵ = 1.93 mm1
α = 79.476 (2)°T = 100 K
β = 85.438 (5)°Plates, colourless
γ = 83.214 (3)°0.25 × 0.15 × 0.1 mm
V = 848.14 (7) Å3

Data collection

Nonius KappaCCD diffractometer3843 independent reflections
Radiation source: fine-focus sealed X-ray tube3711 reflections with I > 2σ(I)
graphiteRint = 0.064
[var phi] scans, and ω scans with κ offsetsθmax = 27.4°, θmin = 2.7°
Absorption correction: multi-scan (SADABS; Sheldrick,1996)h = −9→9
Tmin = 0.644, Tmax = 0.831k = −9→9
10950 measured reflectionsl = −19→19

Refinement

Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.019H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.048w = 1/[σ2(Fo2) + (0.0154P)2 + 0.4426P] where P = (Fo2 + 2Fc2)/3
S = 1.11(Δ/σ)max = 0.002
3843 reflectionsΔρmax = 0.77 e Å3
216 parametersΔρmin = −0.54 e Å3
0 restraintsExtinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.08 (2)

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2)

xyzUiso*/Ueq
Cd10.066723 (15)0.225860 (16)0.280951 (8)0.01066 (5)
Cl1−0.04670 (6)0.54257 (6)0.24433 (3)0.01616 (9)
Cl20.36325 (5)0.13754 (7)0.34349 (3)0.01814 (10)
Cl30.14704 (6)0.17937 (6)0.11755 (3)0.01524 (9)
Cl4−0.15980 (5)0.01360 (6)0.32005 (3)0.01418 (9)
O1−0.01715 (17)0.28215 (19)0.45064 (9)0.0176 (3)
N4−0.3242 (2)0.2622 (2)0.47014 (11)0.0130 (3)
N5−0.38183 (19)0.3218 (2)0.60861 (10)0.0134 (3)
N6−0.6224 (2)0.2535 (2)0.53371 (12)0.0179 (3)
C5−0.1579 (2)0.2895 (2)0.49571 (12)0.0127 (3)
C6−0.4526 (2)0.2762 (2)0.53994 (12)0.0126 (3)
C7−0.1888 (2)0.3305 (3)0.59036 (12)0.0144 (4)
H7A−0.12080.24270.6330.017*
H7B−0.15650.44810.59290.017*
C8−0.4703 (3)0.3343 (3)0.69777 (13)0.0213 (4)
H8A−0.42730.42920.72080.026*
H8B−0.4440.22390.73830.026*
H8C−0.59760.3580.69260.026*
O20.40943 (18)0.36919 (18)−0.10195 (9)0.0191 (3)
N10.2474 (2)0.5415 (2)−0.00578 (11)0.0139 (3)
C10.3552 (2)0.5126 (2)−0.08243 (12)0.0138 (3)
C20.3922 (2)0.6952 (2)−0.13185 (12)0.0127 (3)
H2A0.520.7038−0.14230.015*
H2B0.33640.7239−0.18930.015*
N20.1430 (2)0.7800 (2)0.07081 (11)0.0176 (3)
N30.3113 (2)0.8115 (2)−0.06971 (10)0.0129 (3)
C30.2295 (2)0.7185 (2)0.00098 (12)0.0130 (3)
C40.3227 (3)1.0033 (2)−0.08903 (13)0.0166 (4)
H4A0.25741.0553−0.14130.02*
H4B0.44611.0256−0.10040.02*
H4C0.27221.0551−0.03810.02*
H4−0.340 (3)0.224 (3)0.4298 (17)0.017 (6)*
H66−0.689 (4)0.238 (3)0.5785 (19)0.032 (7)*
H6−0.653 (4)0.215 (4)0.486 (2)0.038 (8)*
H10.212 (3)0.462 (3)0.0292 (17)0.024 (6)*
H220.092 (3)0.704 (3)0.1156 (17)0.024 (6)*
H20.142 (3)0.884 (4)0.0753 (18)0.030 (7)*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
Cd10.00992 (7)0.01213 (8)0.01001 (7)−0.00125 (5)−0.00016 (5)−0.00229 (5)
Cl10.0200 (2)0.0126 (2)0.0151 (2)0.00070 (16)−0.00008 (16)−0.00248 (16)
Cl20.01099 (18)0.0271 (3)0.0158 (2)0.00115 (16)−0.00235 (15)−0.00372 (18)
Cl30.0220 (2)0.0142 (2)0.0106 (2)−0.00484 (16)0.00282 (16)−0.00459 (16)
Cl40.01278 (18)0.0140 (2)0.0155 (2)−0.00334 (15)0.00140 (15)−0.00161 (16)
O10.0146 (6)0.0226 (7)0.0159 (7)−0.0034 (5)0.0043 (5)−0.0055 (5)
N40.0150 (7)0.0162 (8)0.0090 (8)−0.0040 (6)0.0002 (6)−0.0044 (6)
N50.0122 (7)0.0171 (8)0.0110 (7)−0.0009 (6)0.0017 (5)−0.0042 (6)
N60.0132 (7)0.0249 (9)0.0151 (8)−0.0055 (6)−0.0003 (6)−0.0005 (7)
C50.0147 (8)0.0111 (9)0.0121 (9)−0.0020 (6)0.0001 (6)−0.0013 (7)
C60.0144 (8)0.0101 (8)0.0120 (8)−0.0014 (6)0.0008 (6)0.0009 (7)
C70.0130 (8)0.0181 (9)0.0129 (9)−0.0014 (6)0.0001 (6)−0.0052 (7)
C80.0223 (9)0.0278 (11)0.0132 (9)−0.0003 (8)0.0066 (7)−0.0072 (8)
O20.0242 (7)0.0130 (7)0.0206 (7)0.0005 (5)−0.0015 (5)−0.0059 (5)
N10.0178 (7)0.0111 (8)0.0125 (8)−0.0033 (6)0.0006 (6)−0.0009 (6)
C10.0137 (8)0.0155 (9)0.0130 (9)−0.0013 (6)−0.0040 (7)−0.0032 (7)
C20.0148 (8)0.0135 (9)0.0102 (8)−0.0009 (6)0.0008 (6)−0.0039 (7)
N20.0241 (8)0.0143 (9)0.0143 (8)−0.0038 (6)0.0052 (6)−0.0039 (7)
N30.0170 (7)0.0105 (8)0.0116 (7)−0.0018 (6)0.0014 (6)−0.0034 (6)
C30.0140 (8)0.0125 (9)0.0129 (9)−0.0022 (6)−0.0019 (6)−0.0021 (7)
C40.0226 (9)0.0115 (9)0.0158 (9)−0.0026 (7)0.0017 (7)−0.0031 (7)

Geometric parameters (Å, °)

Cd1—Cl12.4571 (5)C8—H8B0.96
Cd1—Cl42.4596 (4)C8—H8C0.96
Cd1—Cl22.4627 (4)O2—C11.208 (2)
Cd1—Cl32.5678 (4)N1—C31.371 (2)
Cd1—O12.6854 (13)N1—C11.394 (2)
O1—C51.213 (2)N1—H10.79 (3)
N4—C61.380 (2)C1—C21.508 (3)
N4—C51.387 (2)C2—N31.460 (2)
N4—H40.75 (2)C2—H2A0.97
N5—C61.319 (2)C2—H2B0.97
N5—C71.463 (2)N2—C31.325 (2)
N5—C81.466 (2)N2—H220.90 (3)
N6—C61.322 (2)N2—H20.81 (3)
N6—H660.81 (3)N3—C31.321 (2)
N6—H60.87 (3)N3—C41.459 (2)
C5—C71.511 (2)C4—H4A0.96
C7—H7A0.97C4—H4B0.96
C7—H7B0.97C4—H4C0.96
C8—H8A0.96
Cl1—Cd1—Cl4116.512 (15)N5—C8—H8B109.5
Cl1—Cd1—Cl2120.122 (17)H8A—C8—H8B109.5
Cl4—Cd1—Cl2117.621 (16)N5—C8—H8C109.5
Cl1—Cd1—Cl396.649 (15)H8A—C8—H8C109.5
Cl4—Cd1—Cl398.074 (15)H8B—C8—H8C109.5
Cl2—Cd1—Cl399.319 (15)C3—N1—C1110.39 (15)
Cl1—Cd1—O182.18 (3)C3—N1—H1127.6 (18)
Cl4—Cd1—O182.85 (3)C1—N1—H1121.8 (18)
Cl2—Cd1—O180.95 (3)O2—C1—N1125.86 (18)
Cl3—Cd1—O1178.75 (3)O2—C1—C2128.57 (17)
C5—O1—Cd1132.55 (13)N1—C1—C2105.55 (15)
C6—N4—C5110.28 (15)N3—C2—C1102.80 (14)
C6—N4—H4122.8 (18)N3—C2—H2A111.2
C5—N4—H4125.3 (18)C1—C2—H2A111.2
C6—N5—C7110.56 (14)N3—C2—H2B111.2
C6—N5—C8126.70 (15)C1—C2—H2B111.2
C7—N5—C8122.02 (15)H2A—C2—H2B109.1
C6—N6—H66120.4 (19)C3—N2—H22119.4 (15)
C6—N6—H6119.0 (19)C3—N2—H2120.6 (19)
H66—N6—H6117 (3)H22—N2—H2120 (2)
O1—C5—N4126.58 (18)C3—N3—C4127.85 (15)
O1—C5—C7127.43 (17)C3—N3—C2110.50 (15)
N4—C5—C7105.99 (14)C4—N3—C2121.64 (15)
N5—C6—N6126.98 (17)N3—C3—N2127.02 (17)
N5—C6—N4110.34 (15)N3—C3—N1110.42 (15)
N6—C6—N4122.61 (17)N2—C3—N1122.56 (17)
N5—C7—C5102.69 (14)N3—C4—H4A109.5
N5—C7—H7A111.2N3—C4—H4B109.5
C5—C7—H7A111.2H4A—C4—H4B109.5
N5—C7—H7B111.2N3—C4—H4C109.5
C5—C7—H7B111.2H4A—C4—H4C109.5
H7A—C7—H7B109.1H4B—C4—H4C109.5
N5—C8—H8A109.5
Cl1—Cd1—O1—C579.99 (16)O1—C5—C7—N5179.62 (18)
Cl4—Cd1—O1—C5−38.13 (16)N4—C5—C7—N5−0.20 (19)
Cl2—Cd1—O1—C5−157.67 (17)C3—N1—C1—O2172.47 (17)
Cd1—O1—C5—N42.7 (3)C3—N1—C1—C2−5.74 (19)
Cd1—O1—C5—C7−177.09 (13)O2—C1—C2—N3−172.51 (18)
C6—N4—C5—O1178.19 (18)N1—C1—C2—N35.63 (18)
C6—N4—C5—C7−2.0 (2)C1—C2—N3—C3−3.83 (19)
C7—N5—C6—N6179.08 (18)C1—C2—N3—C4177.23 (15)
C8—N5—C6—N68.7 (3)C4—N3—C3—N2−1.6 (3)
C7—N5—C6—N4−3.8 (2)C2—N3—C3—N2179.59 (18)
C8—N5—C6—N4−174.16 (17)C4—N3—C3—N1179.35 (16)
C5—N4—C6—N53.7 (2)C2—N3—C3—N10.5 (2)
C5—N4—C6—N6−179.05 (17)C1—N1—C3—N33.5 (2)
C6—N5—C7—C52.43 (19)C1—N1—C3—N2−175.66 (17)
C8—N5—C7—C5173.30 (16)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
N1—H1···Cl30.79 (2)2.41 (2)3.1840 (16)168 (2)
N2—H2···Cl3i0.80 (3)2.48 (3)3.273 (2)170 (3)
N4—H4···Cl40.75 (2)2.70 (2)3.2967 (17)139 (2)
N6—H6···Cl2ii0.88 (3)2.32 (3)3.1673 (18)161 (3)
N2—H22···Cl10.90 (2)2.34 (2)3.2368 (18)171 (2)
N6—H66···Cl4iii0.81 (3)2.55 (3)3.2117 (17)140 (2)

Symmetry codes: (i) x, y+1, z; (ii) x−1, y, z; (iii) −x−1, −y, −z+1.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: BT2978).

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