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2-Amino-4-methyl­pyridinium 2-nitro­benzoate

aDepartment of Physics, Anna University, Chennai 600 025, India, and bCentre of Advanced Study in Crystallography and Biophysics, University of Madras, Guindy Campus, Chennai 600 025, India
*Correspondence e-mail: shirai2011@gmail.com

(Received 18 April 2013; accepted 11 May 2013; online 18 May 2013)

In the title mol­ecular salt, C6H9N2+·C7H4NO4, the original pyridine N atom of 2-amino-4-methyl­pyridine is protonated and the carb­oxylic acid group of nitro­benzoic acid is deprotonated. In the crystal, the ions are linked by N—H⋯O hydrogen bonds, forming chains propagating along [001]. The chains are linked via C—H⋯O hydrogen bonds, forming two-dimensional networks lying parallel to the bc plane.

Related literature

For related structures, see: Navarro Ranninger et al. (1985[Navarro Ranninger, M.-C., Martínez-Carrera, S. & García-Blanco, S. (1985). Acta Cryst. C41, 21-22.]); Luque et al. (1997[Luque, A., Sertucha, J., Lezama, L., Rojo, T. & Roman, P. (1997). J. Chem. Soc. Dalton Trans. pp. 847-854.]); Qin et al. (1999[Qin, J. G., Su, N. B., Dai, C. Y., Yang, C. L., Liu, D. Y., Day, M. W., Wu, B. C. & Chen, C. T. (1999). Polyhedron, 18, 3461-3464.]); Jin et al. (2001[Jin, Z. M., Pan, Y. J., Hu, M. L. & Shen, L. (2001). J. Chem. Crystallogr. 31, 191-195.]); Albrecht et al. (2003[Albrecht, A. S., Landee, C. P. & Turnbull, M. M. (2003). J. Chem. Crystallogr. 33, 269-276.]); Kvick & Noordik (1977[Kvick, Å. & Noordik, J. (1977). Acta Cryst. B33, 2862-2866.]).

[Scheme 1]

Experimental

Crystal data
  • C6H9N2+·C7H4NO4

  • Mr = 275.26

  • Monoclinic, P 21 /c

  • a = 12.2049 (3) Å

  • b = 9.8463 (2) Å

  • c = 11.5405 (2) Å

  • β = 107.106 (1)°

  • V = 1325.51 (5) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.11 mm−1

  • T = 293 K

  • 0.30 × 0.25 × 0.20 mm

Data collection
  • Bruker SMART APEXII area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2008[Bruker (2008). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.969, Tmax = 0.979

  • 12523 measured reflections

  • 3289 independent reflections

  • 2644 reflections with I > 2σ(I)

  • Rint = 0.023

Refinement
  • R[F2 > 2σ(F2)] = 0.041

  • wR(F2) = 0.125

  • S = 1.06

  • 3289 reflections

  • 195 parameters

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.26 e Å−3

  • Δρmin = −0.18 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N3—H3A⋯O4i 0.933 (18) 1.752 (19) 2.6746 (16) 169.5 (17)
N4—H4A⋯O3i 0.923 (19) 1.972 (19) 2.8734 (18) 164.9 (17)
N4—H4B⋯O4ii 0.871 (19) 2.033 (19) 2.8937 (16) 169.7 (18)
C11—H11⋯O3iii 0.93 2.58 3.3624 (16) 142
Symmetry codes: (i) -x+2, -y, -z+1; (ii) [-x+2, y+{\script{1\over 2}}, -z+{\script{3\over 2}}]; (iii) [x, -y+{\script{1\over 2}}, z+{\script{1\over 2}}].

Data collection: APEX2 (Bruker, 2008[Bruker (2008). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2008[Bruker (2008). APEX2, SAINT and SADABS. 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: ORTEP-3 for Windows (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]); software used to prepare material for publication: SHELXL97 and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Supporting information


Comment top

There are numerous examples of 2-amino-substituted pyridine compounds in which the 2-aminopyridines act as neutral ligands (Navarro Ranninger et al., 1985; Luque et al., 1997; Qin et al., 1999) or as protonated cations (Luque et al., 1997; Jin et al., 2001; Albrecht et al., 2003). In order to study hydrogen bonding interactions in such systems, we synthesized the title salt and report herein on its crystal structure.

In the title molecular salt, Fig. 1, the pyridine N atom of 2-amino-4-methylpyridine is protonated and the carboxyl group of nitrobenzoic acid is deprotonated. The amine attached with the pyridine ring deviates by -0.0098 (15) Å. The methyl carbon atom C13 attached with the pyridine ring deviates by -0.0261 (17) Å.

In the crystal, the pyridine ring (N3,C8-C12) makes a dihedral angle of 12.13 (7)° with the nitrobenzoate ring (C1-C6). The ions are linked by N–H···O hydrogen bonds forming chains propagating along [001]; see Table 1 and Fig. 2. These chains are linked via C–H···O hydrogen bonds forming two-dimensional networks lying parallel to the bc plane (Table 1).

Related literature top

For related structures, see: Navarro Ranninger et al. (1985); Luque et al. (1997); Qin et al. (1999); Jin et al. (2001); Albrecht et al. (2003); Kvick & Noordik (1977).

Experimental top

2-amino-4-methylpyridine (C6H8N2) and 2-nitrobenzoic acid (C7H5N1O4) were mixed in an equimolar ratio (1:1) using ethanol as solvent and stirred well. The solution was filtered into a clean beaker and optimally closed. Colourless block-like crystals were obtained by slow evaporation at room temperature in 15 days.

Refinement top

The NH and NH2 H atoms were located in a difference Fourier map and freely refined. The C-bound H atoms were positioned geometrically and refined using a riding model: C—H = 0.93 and 0.96 Å for CH and CH3 H atoms, respectively, with Uiso(H) = 1.5Ueq(C) for CH3 H atoms and = 1.2Ueq(C) for other H atoms.

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: ORTEP-3 for Windows (Farrugia, 2012); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound, with atom labelling. Displacement ellipsoids are drawn at the 30% probability level.
[Figure 2] Fig. 2. The crystal packing of the title compound viewed along the a axis. The hydrogen bonds are shown as dashed lines (see Table 1 for details; C-bound H-atoms have been omitted for clarity).
2-Amino-4-methylpyridinium 2-nitrobenzoate top
Crystal data top
C6H9N2+·C7H4NO4F(000) = 576
Mr = 275.26Dx = 1.379 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 3289 reflections
a = 12.2049 (3) Åθ = 1.8–28.4°
b = 9.8463 (2) ŵ = 0.11 mm1
c = 11.5405 (2) ÅT = 293 K
β = 107.106 (1)°Block, colourless
V = 1325.51 (5) Å30.30 × 0.25 × 0.20 mm
Z = 4
Data collection top
Bruker SMART APEXII area-detector
diffractometer
3289 independent reflections
Radiation source: fine-focus sealed tube2644 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.023
ω and ϕ scansθmax = 28.4°, θmin = 1.8°
Absorption correction: multi-scan
(SADABS; Bruker, 2008)
h = 1316
Tmin = 0.969, Tmax = 0.979k = 1213
12523 measured reflectionsl = 1215
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.041H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.125 w = 1/[σ2(Fo2) + (0.0582P)2 + 0.2995P]
where P = (Fo2 + 2Fc2)/3
S = 1.06(Δ/σ)max = 0.004
3289 reflectionsΔρmax = 0.26 e Å3
195 parametersΔρmin = 0.18 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: 0.031 (3)
Crystal data top
C6H9N2+·C7H4NO4V = 1325.51 (5) Å3
Mr = 275.26Z = 4
Monoclinic, P21/cMo Kα radiation
a = 12.2049 (3) ŵ = 0.11 mm1
b = 9.8463 (2) ÅT = 293 K
c = 11.5405 (2) Å0.30 × 0.25 × 0.20 mm
β = 107.106 (1)°
Data collection top
Bruker SMART APEXII area-detector
diffractometer
3289 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2008)
2644 reflections with I > 2σ(I)
Tmin = 0.969, Tmax = 0.979Rint = 0.023
12523 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0410 restraints
wR(F2) = 0.125H atoms treated by a mixture of independent and constrained refinement
S = 1.06Δρmax = 0.26 e Å3
3289 reflectionsΔρmin = 0.18 e Å3
195 parameters
Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 > 2sigma(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
C10.61383 (11)0.04795 (13)0.39832 (12)0.0428 (3)
C20.53048 (13)0.13768 (17)0.40961 (15)0.0577 (4)
H20.46060.14370.34940.069*
C30.55274 (15)0.21813 (17)0.51177 (17)0.0631 (4)
H30.49790.27980.52020.076*
C40.65544 (15)0.20749 (16)0.60095 (15)0.0578 (4)
H40.66940.26050.67050.069*
C50.73827 (12)0.11780 (14)0.58743 (12)0.0469 (3)
H50.80760.11140.64840.056*
C60.72002 (10)0.03729 (12)0.48485 (10)0.0367 (3)
C70.81856 (11)0.04361 (12)0.46565 (11)0.0383 (3)
C80.87671 (12)0.30082 (14)0.40898 (11)0.0472 (3)
H80.86420.25440.33600.057*
C90.80301 (12)0.39954 (14)0.41863 (12)0.0483 (3)
H90.74070.42160.35260.058*
C100.82151 (11)0.46900 (13)0.52995 (12)0.0429 (3)
C110.91448 (12)0.43446 (13)0.62498 (11)0.0423 (3)
H110.92780.47940.69870.051*
C120.99021 (11)0.33137 (13)0.61202 (11)0.0399 (3)
C130.73825 (14)0.57626 (16)0.54149 (15)0.0597 (4)
H13A0.75590.60440.62460.090*
H13B0.66180.54030.51530.090*
H13C0.74370.65280.49200.090*
N10.58459 (11)0.04327 (14)0.29302 (11)0.0562 (3)
N30.96840 (10)0.26833 (11)0.50367 (9)0.0417 (3)
N41.08159 (12)0.29199 (15)0.70053 (11)0.0561 (3)
O10.53069 (14)0.00397 (18)0.19509 (11)0.0954 (5)
O20.61421 (12)0.16147 (12)0.30903 (11)0.0771 (4)
O30.83221 (9)0.04027 (11)0.36362 (9)0.0547 (3)
O40.88257 (8)0.10404 (11)0.55661 (8)0.0518 (3)
H4B1.0969 (15)0.3317 (18)0.7709 (17)0.059 (5)*
H4A1.1221 (15)0.2174 (19)0.6872 (16)0.065 (5)*
H3A1.0192 (15)0.2040 (18)0.4898 (16)0.064 (5)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0439 (7)0.0438 (6)0.0385 (6)0.0005 (5)0.0088 (5)0.0079 (5)
C20.0448 (7)0.0628 (9)0.0619 (9)0.0129 (6)0.0101 (6)0.0191 (7)
C30.0659 (10)0.0565 (9)0.0744 (11)0.0243 (7)0.0323 (9)0.0124 (8)
C40.0738 (10)0.0519 (8)0.0533 (8)0.0144 (7)0.0272 (8)0.0016 (6)
C50.0513 (7)0.0510 (7)0.0379 (6)0.0061 (6)0.0122 (6)0.0011 (5)
C60.0409 (6)0.0363 (6)0.0334 (6)0.0026 (5)0.0118 (5)0.0053 (4)
C70.0410 (6)0.0395 (6)0.0335 (6)0.0019 (5)0.0095 (5)0.0001 (5)
C80.0572 (8)0.0520 (7)0.0299 (6)0.0070 (6)0.0089 (5)0.0020 (5)
C90.0504 (7)0.0528 (7)0.0368 (6)0.0087 (6)0.0053 (5)0.0017 (5)
C100.0460 (7)0.0396 (6)0.0435 (7)0.0020 (5)0.0139 (6)0.0008 (5)
C110.0503 (7)0.0417 (6)0.0352 (6)0.0010 (5)0.0130 (5)0.0047 (5)
C120.0460 (7)0.0416 (6)0.0321 (6)0.0010 (5)0.0115 (5)0.0005 (5)
C130.0599 (9)0.0541 (8)0.0621 (9)0.0150 (7)0.0131 (7)0.0064 (7)
N10.0510 (7)0.0649 (8)0.0446 (7)0.0082 (6)0.0016 (5)0.0002 (6)
N30.0479 (6)0.0452 (6)0.0318 (5)0.0083 (5)0.0114 (4)0.0001 (4)
N40.0627 (8)0.0625 (8)0.0355 (6)0.0192 (6)0.0026 (5)0.0050 (5)
O10.1008 (11)0.1144 (12)0.0473 (7)0.0141 (9)0.0148 (7)0.0027 (7)
O20.1014 (10)0.0528 (7)0.0671 (8)0.0131 (6)0.0094 (7)0.0113 (6)
O30.0669 (7)0.0634 (6)0.0391 (5)0.0162 (5)0.0237 (5)0.0062 (4)
O40.0522 (6)0.0648 (6)0.0372 (5)0.0209 (5)0.0111 (4)0.0079 (4)
Geometric parameters (Å, º) top
C1—C21.382 (2)C9—C101.4137 (19)
C1—C61.3880 (17)C9—H90.9300
C1—N11.4682 (18)C10—C111.3688 (18)
C2—C31.379 (3)C10—C131.4985 (19)
C2—H20.9300C11—C121.4101 (18)
C3—C41.372 (2)C11—H110.9300
C3—H30.9300C12—N41.3295 (17)
C4—C51.385 (2)C12—N31.3505 (16)
C4—H40.9300C13—H13A0.9600
C5—C61.3872 (18)C13—H13B0.9600
C5—H50.9300C13—H13C0.9600
C6—C71.5122 (17)N1—O21.2165 (18)
C7—O31.2372 (15)N1—O11.2203 (17)
C7—O41.2585 (15)N3—H3A0.933 (18)
C8—C91.3510 (19)N4—H4B0.871 (19)
C8—N31.3526 (17)N4—H4A0.923 (19)
C8—H80.9300
C2—C1—C6122.54 (13)C10—C9—H9120.3
C2—C1—N1117.55 (13)C11—C10—C9118.75 (12)
C6—C1—N1119.83 (12)C11—C10—C13121.87 (12)
C3—C2—C1118.83 (14)C9—C10—C13119.37 (12)
C3—C2—H2120.6C10—C11—C12120.57 (12)
C1—C2—H2120.6C10—C11—H11119.7
C4—C3—C2120.27 (14)C12—C11—H11119.7
C4—C3—H3119.9N4—C12—N3118.01 (12)
C2—C3—H3119.9N4—C12—C11123.81 (12)
C3—C4—C5120.01 (15)N3—C12—C11118.18 (11)
C3—C4—H4120.0C10—C13—H13A109.5
C5—C4—H4120.0C10—C13—H13B109.5
C4—C5—C6121.40 (13)H13A—C13—H13B109.5
C4—C5—H5119.3C10—C13—H13C109.5
C6—C5—H5119.3H13A—C13—H13C109.5
C5—C6—C1116.90 (11)H13B—C13—H13C109.5
C5—C6—C7119.41 (11)O2—N1—O1124.08 (15)
C1—C6—C7123.29 (11)O2—N1—C1118.07 (12)
O3—C7—O4125.59 (12)O1—N1—C1117.84 (14)
O3—C7—C6117.46 (11)C12—N3—C8122.02 (11)
O4—C7—C6116.88 (10)C12—N3—H3A120.8 (11)
C9—C8—N3121.08 (12)C8—N3—H3A117.1 (11)
C9—C8—H8119.5C12—N4—H4B119.2 (11)
N3—C8—H8119.5C12—N4—H4A118.3 (11)
C8—C9—C10119.39 (12)H4B—N4—H4A122.2 (16)
C8—C9—H9120.3
C6—C1—C2—C31.2 (2)N3—C8—C9—C100.6 (2)
N1—C1—C2—C3175.64 (14)C8—C9—C10—C110.4 (2)
C1—C2—C3—C40.8 (2)C8—C9—C10—C13178.59 (14)
C2—C3—C4—C51.4 (3)C9—C10—C11—C120.1 (2)
C3—C4—C5—C60.0 (2)C13—C10—C11—C12178.84 (13)
C4—C5—C6—C11.9 (2)C10—C11—C12—N4179.53 (14)
C4—C5—C6—C7171.12 (13)C10—C11—C12—N30.1 (2)
C2—C1—C6—C52.48 (19)C2—C1—N1—O2137.16 (16)
N1—C1—C6—C5174.27 (12)C6—C1—N1—O239.75 (19)
C2—C1—C6—C7170.21 (12)C2—C1—N1—O141.9 (2)
N1—C1—C6—C713.05 (18)C6—C1—N1—O1141.19 (15)
C5—C6—C7—O3134.09 (13)N4—C12—N3—C8179.29 (13)
C1—C6—C7—O338.42 (18)C11—C12—N3—C80.33 (19)
C5—C6—C7—O443.01 (17)C9—C8—N3—C120.6 (2)
C1—C6—C7—O4144.48 (13)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N3—H3A···O4i0.933 (18)1.752 (19)2.6746 (16)169.5 (17)
N4—H4A···O3i0.923 (19)1.972 (19)2.8734 (18)164.9 (17)
N4—H4B···O4ii0.871 (19)2.033 (19)2.8937 (16)169.7 (18)
C11—H11···O3iii0.932.583.3624 (16)142
Symmetry codes: (i) x+2, y, z+1; (ii) x+2, y+1/2, z+3/2; (iii) x, y+1/2, z+1/2.

Experimental details

Crystal data
Chemical formulaC6H9N2+·C7H4NO4
Mr275.26
Crystal system, space groupMonoclinic, P21/c
Temperature (K)293
a, b, c (Å)12.2049 (3), 9.8463 (2), 11.5405 (2)
β (°) 107.106 (1)
V3)1325.51 (5)
Z4
Radiation typeMo Kα
µ (mm1)0.11
Crystal size (mm)0.30 × 0.25 × 0.20
Data collection
DiffractometerBruker SMART APEXII area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2008)
Tmin, Tmax0.969, 0.979
No. of measured, independent and
observed [I > 2σ(I)] reflections
12523, 3289, 2644
Rint0.023
(sin θ/λ)max1)0.668
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.041, 0.125, 1.06
No. of reflections3289
No. of parameters195
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.26, 0.18

Computer programs: APEX2 (Bruker, 2008), SAINT (Bruker, 2008), SHELXS97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 2012), SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N3—H3A···O4i0.933 (18)1.752 (19)2.6746 (16)169.5 (17)
N4—H4A···O3i0.923 (19)1.972 (19)2.8734 (18)164.9 (17)
N4—H4B···O4ii0.871 (19)2.033 (19)2.8937 (16)169.7 (18)
C11—H11···O3iii0.932.583.3624 (16)142
Symmetry codes: (i) x+2, y, z+1; (ii) x+2, y+1/2, z+3/2; (iii) x, y+1/2, z+1/2.
 

Acknowledgements

The authors thank the TBI X-ray facility, CAS in Crystallography and Biophysics, University of Madras, India, for the data collection. TS and DV thank the UGC (SAP–CAS) for the departmental facilties. TS also thanks DST Inspire for financial assistance.

References

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