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Powder diffraction study of 1,2:3,4-dibenzanthracene

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aDepartment of Pharmaceutical Sciences, University of Strathclyde, 27 Taylor Street, Glasgow G4 0NR, Scotland, and bISIS Facility, Rutherford Appleton Laboratory, Chilton, Didcot, Oxfordshire OX11 0QX, England
*Correspondence e-mail: alastair.florence@strath.ac.uk

(Received 5 April 2005; accepted 19 April 2005; online 27 April 2005)

The crystal structure of 1,2:3,4-dibenzanthracene, C22H14, was solved by simulated annealing from laboratory X-ray powder diffraction data collected at room temperature to 1.8 Å resolution. Subsequent Rietveld refinement yielded an Rwp value of 0.036. The molecules crystallize in space group P21 with two independent molecules in the asymmetric unit which pack in a stacked arrangement along the b axis.

Comment

The title compound, (I)[link], was used as supplied and its crystal structure was solved by simulated annealing using laboratory X-ray powder diffraction data (Fig. 1[link]). The compound crystallizes in space group P21 with two independent mol­ecules in the asymmetric unit (Fig. 2[link]).

[Scheme 1]

The crystal packing adopts a γ-type structure, with mol­ecules stacked in the direction of the b axis (Desiraju & Gavezzotti, 1989[Desiraju, G. R. & Gavezzotti A. (1989). Acta Cryst. B45, 473-482.]). The distance between the centres of mass of neighbouring mol­ecules within each stack (Rn) equals the shortest cell axis, 5.062 Å, and the perpendicular distance between the mol­ecular planes within each stack (Rip) is 3.740 Å, with an offset angle α = 43° (Fig. 3[link]).

[Figure 1]
Figure 1
Final observed (points), calculated (line) and difference [(yobs − ycalc)/σ(yobs)] profiles for the Rietveld refinement of (I)[link].
[Figure 2]
Figure 2
The atomic arrangement in (I)[link], showing the two mol­ecules in the asymmetric unit. The dihedral angle between the least-squares planes through each of the mol­ecules is 47.8 (8)°. Isotropic displacement spheres are shown at the 50% probability level.
[Figure 3]
Figure 3
Top: view showing the mol­ecular stacking along the b axis in (I)[link] for both unique mol­ecules. Mol­ecules within each stack form offset face-to-face attractive contacts (Hunter et al., 1990[Hunter, A. & Sanders, J. K. M. (1990). J. Am. Chem. Soc. 112, 5525-5534.]). Bottom: view down the b axis onto the ac plane. The crystal packing arrangement is stabilized by a series of C—H⋯π contacts between adjacent stacks, with H⋯ring-centroid (Cg) distances in the range 2.9 (5)–3.3 (5) Å. Dashed lines represent three of these contacts. (1) C4A—H26ACg of the ring C1–C6 in the mol­ecule at (x, 1 + y, z) [H26ACg 2.9 (5) Å], (2) C2A—H24ACg of the ring C5A–C10A in the mol­ecule at (1 − x, [{1\over 2}] + y, 1 − z) [H24ACg 3.2 (6) Å] and (3) the symmetry equivalent of (1), where H26A and Cg are in the mol­ecules at (1 − x, [{1\over 2}] + y, 1 − z).

Experimental

1,2:3,4-Dibenzanthracene (Sigma–Aldrich) was lightly ground in a mortar, loaded into a 0.7 mm borosilicate glass capillary and mounted on the diffractometer. Data were collected from a sample in a rotating 0.7 mm borosilicate glass capillary using a variable count time scheme (Hill & Madsen, 2002[Hill, R. J. & Madsen, I. C. (2002). Structure Determination from Powder Diffraction Data, edited by W. I. F. David, K. Shankland, L. B. McCusker & Ch. Baerlocher, pp. 114-116. Oxford University Press.]).

Crystal data
  • C22H14

  • Mr = 278.33

  • Monoclinic, P 21

  • a = 18.2966 (5) Å

  • b = 5.06225 (10) Å

  • c = 15.7245 (4) Å

  • β = 104.5574 (15)°

  • V = 1409.68 (6) Å3

  • Z = 4

  • Dx = 1.311 Mg m−3

  • Cu Kα1 radiation

  • μ = 0.56 mm−1

  • T = 295 K

  • Specimen shape: cylinder

  • 12 × 0.7 mm

  • Specimen prepared at 295 K

  • Particle morphology: visual estimate, flat plate, pale yellow

Data collection
  • Bruker D8 Advance diffractometer

  • Specimen mounting: 0.7 mm borosilicate capillary

  • Specimen mounted in transmission mode

  • Scan method: step

  • Absorption correction: none

  • 2θmin = 4, 2θmax = 69.8°

  • Increment in 2θ = 0.014°

  • h = −13 → 13

  • k = −3 → 3

  • l = −9 → 11

Refinement
  • Refinement on F2

  • Rp = 0.036

  • Rwp = 0.036

  • Rexp = 0.014

  • S = 2.69

  • Increment in 2θ = 0.014°

  • Wavelength of incident radiation: 1.54056 Å

  • Profile function: fundamental parameters with axial divergence correction

  • 739 reflections

  • 241 parameters

  • Only H-atom coordinates refined

  • w = 1/σ(yobs)2

  • (Δ/σ)max = 0.011

  • Preferred orientation correction: a spherical harmonics-based preferred orientation correction was applied with TOPAS during the Rietveld refinement.

The diffraction pattern indexed to a monoclinic cell [F(25) = 210.1, M(25) = 71.8; DICVOL-91 (Boultif & Louer, 1991[Boultif, A. & Louer, D. (1991). J. Appl. Cryst. 24, 987-993.])], and space group P21 was assigned from volume considerations and a statistical consideration of the systematic absences. The data set was background-subtracted and truncated to 2θ = 51.9° for Pawley fitting (Pawley, 1981[Pawley, G. S. (1981). J. Appl. Cryst. 14, 357-361.]; χPawley2 = 3.96), and the structure was solved using the simulated annealing (SA) global optimization procedure of David et al. (1998[David, W. I. F., Shankland, K. & Shankland, N. (1998). Chem. Commun. pp. 931-932.]), as implemented in the DASH computer program (David et al., 2001[David, W. I. F., Shankland, K., Cole, J., Maginn, S., Motherwell, W. D. S. & Taylor, R. (2001). DASH. Version 2.1. Cambridge Crystallographic Data Centre, 12 Union Road, Cambridge, England.]). The SA structure solution involved the optimization of two independent fragments in the asymmetric unit, totalling 12 degrees of freedom. The best SA solution had a favourable χSA2/χPawley2 ratio of 4.53 and a chemically reasonable packing arrangement, and exhibited no significant misfit to the data. The solved structure was then refined with the full data set (2θ 4–69.8°) using a restrained Rietveld method (Rietveld, 1969[Rietveld, H. M. (1969). J. Appl. Cryst. 2, 65-71.]), as implemented in TOPAS (Coelho, 2003[Coelho, A. A. (2003). TOPAS User's Manual. Bruker AXS GmbH, Karlsruhe, Germany.]), with the value of Rwp falling from 0.146 to 0.036 during the refinement. The y coordinate of atom C1 was fixed and all remaining atomic positions (including H atoms) were refined, subject to a series of restraints on bond lengths, bond angles and planarity. Inclusion of a March–Dollase (Dollase, 1986[Dollase, W. A. (1986). J. Appl. Cryst. 19, 267-272.]) preferred orientation correction indicated the presence of mild (1.16) preferred orientation along the [010] direction, and a spherical harmonics correction of intensities for preferred orientation was applied in the final refinement. The observed and calculated diffraction patterns for the refined crystal structure are shown in Fig. 1[link].

Data collection: DIFFRAC plus XRD Commander (Kienle & Jacob, 2003); cell refinement: TOPAS (Coelho, 2003[Coelho, A. A. (2003). TOPAS User's Manual. Bruker AXS GmbH, Karlsruhe, Germany.]); data reduction: DASH (David et al., 2001[David, W. I. F., Shankland, K., Cole, J., Maginn, S., Motherwell, W. D. S. & Taylor, R. (2001). DASH. Version 2.1. Cambridge Crystallographic Data Centre, 12 Union Road, Cambridge, England.]); structure solution: DASH; structure refinement: TOPAS; molecular graphics: PLATON (Spek, 2003[Spek, A. L. (2003). J. Appl. Cryst. 36, 7-13.]); publication software: enCIFer (Allen et al., 2004[Allen, F. H., Johnson, O., Shields, G. P., Smith, B. R. & Towler, M. (2004). J. Appl. Cryst. 37, 335-338.]).

Supporting information


Computing details top

Data collection: D8-Advance Control Software; cell refinement: Please provide missing details; data reduction: DASH (David et al., 2001); program(s) used to solve structure: DASH; program(s) used to refine structure: TOPAS (Coelho, 2003); molecular graphics: Please provide missing details; software used to prepare material for publication: Please provide missing details.

1,2:5,6-Dibenzanthracene top
Crystal data top
C22H14F(000) = 584
Mr = 278.33Dx = 1.311 Mg m3
Monoclinic, P21Melting point: 500 K
Hall symbol: P 2ybCu Kα1 radiation, λ = 1.54056 Å
a = 18.2966 (5) ŵ = 0.56 mm1
b = 5.06225 (10) ÅT = 295 K
c = 15.7245 (4) ÅParticle morphology: visual estimate, flat plates
β = 104.5574 (15)°pale-yellow
V = 1409.68 (6) Å3cylinder, 10 × 0.7 mm
Z = 4Specimen preparation: Prepared at 295 K
Data collection top
Bruker D8 Advance
diffractometer
Data collection mode: transmission
Radiation source: sealed X-ray tube, Bruker D8Scan method: step
Primary focussing, Ge 111 monochromator2θmin = 4°, 2θmax = 69.8°, 2θstep = 0.014°
Specimen mounting: 0.7 mm borosilicate capillary
Refinement top
Least-squares matrix: selected elements only214 restraints
Rp = 0.0361 constraint
Rwp = 0.036Only H-atom coordinates refined
Rexp = 0.014Weighting scheme based on measured s.u.'s 1/σ(Yobs)2
4544 data points(Δ/σ)max = 0.011
Profile function: Fundamental parameters with axial divergence correctionBackground function: Chebyshev polynomial
241 parametersPreferred orientation correction: A spherical harmonics-based preferred orientation correction was applied with TOPAS during the Rietveld refinement.
Special details top

Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All e.s.d.'s are estimated from the variances of the (full) variance-covariance matrix. The cell e.s.d.'s are taken into account in the estimation of distances, angles and torsion angles

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
C10.305 (3)0.067630.781 (5)0.0465 (10)*
C20.235 (3)0.011 (17)0.724 (3)0.0465 (10)*
C30.283 (3)0.274 (16)0.880 (3)0.0465 (10)*
C40.331 (2)0.085 (17)0.857 (3)0.0465 (10)*
C50.211 (3)0.323 (15)0.824 (3)0.0465 (10)*
C60.187 (3)0.179 (16)0.746 (4)0.0465 (10)*
C70.115 (3)0.228 (15)0.690 (3)0.0465 (10)*
C80.163 (3)0.513 (13)0.847 (3)0.0465 (10)*
C90.092 (3)0.562 (14)0.791 (4)0.0465 (10)*
C100.067 (3)0.419 (14)0.712 (3)0.0465 (10)*
C110.052 (3)0.658 (16)0.679 (4)0.0465 (10)*
C120.005 (3)0.467 (17)0.656 (4)0.0465 (10)*
C130.029 (3)0.323 (16)0.578 (4)0.0465 (10)*
C140.100 (3)0.372 (16)0.522 (3)0.0465 (10)*
C150.148 (3)0.561 (16)0.545 (4)0.0465 (10)*
C160.123 (3)0.706 (16)0.622 (4)0.0465 (10)*
C170.044 (3)0.752 (17)0.813 (4)0.0465 (10)*
C180.028 (3)0.801 (14)0.757 (4)0.0465 (10)*
C190.075 (3)0.991 (18)0.780 (4)0.0465 (10)*
C200.050 (3)1.136 (17)0.858 (4)0.0465 (10)*
C210.021 (3)1.084 (17)0.915 (3)0.0465 (10)*
C220.068 (3)0.896 (16)0.891 (4)0.0465 (10)*
H230.34 (3)0.19 (11)0.76 (3)0.0760*
H240.22 (3)0.11 (9)0.67 (3)0.0760*
H250.30 (3)0.37 (11)0.93 (2)0.0760*
H260.38 (2)0.05 (10)0.90 (3)0.0760*
H270.10 (3)0.13 (10)0.64 (3)0.0760*
H280.18 (2)0.61 (12)0.90 (3)0.0760*
H290.00 (2)0.20 (11)0.56 (3)0.0760*
H300.12 (2)0.28 (9)0.47 (3)0.0760*
H310.196 (17)0.59 (8)0.51 (3)0.0760*
H320.16 (2)0.83 (9)0.64 (3)0.0760*
H330.12 (2)1.03 (12)0.74 (3)0.0760*
H340.08 (2)1.26 (10)0.87 (3)0.0760*
H350.04 (3)1.18 (12)0.97 (3)0.0760*
H360.12 (2)0.86 (9)0.93 (3)0.0760*
C1A0.393 (3)0.174 (16)0.616 (3)0.0465 (10)*
C2A0.421 (3)0.133 (15)0.542 (4)0.0465 (10)*
C3A0.308 (3)0.511 (18)0.538 (4)0.0465 (10)*
C4A0.337 (3)0.364 (18)0.614 (3)0.0465 (10)*
C5A0.335 (3)0.470 (15)0.463 (3)0.0465 (10)*
C6A0.391 (3)0.281 (15)0.465 (4)0.0465 (10)*
C7A0.419 (3)0.240 (17)0.390 (5)0.0465 (10)*
C8A0.306 (3)0.618 (17)0.387 (4)0.0465 (10)*
C9A0.333 (3)0.577 (15)0.312 (4)0.0465 (10)*
C10A0.389 (3)0.388 (17)0.313 (3)0.0465 (10)*
C11A0.386 (3)0.498 (19)0.161 (4)0.0465 (10)*
C12A0.416 (3)0.349 (16)0.237 (4)0.0465 (10)*
C13A0.472 (3)0.159 (16)0.237 (3)0.0465 (10)*
C14A0.499 (3)0.122 (17)0.163 (4)0.0465 (10)*
C15A0.469 (3)0.271 (16)0.087 (4)0.0465 (10)*
C16A0.413 (3)0.460 (15)0.086 (4)0.0465 (10)*
C17A0.303 (3)0.726 (16)0.236 (3)0.0465 (10)*
C18A0.330 (3)0.687 (15)0.161 (4)0.0465 (10)*
C19A0.300 (3)0.838 (16)0.085 (4)0.0465 (10)*
C20A0.244 (3)1.027 (17)0.086 (3)0.0465 (10)*
C21A0.217 (3)1.063 (17)0.161 (5)0.0465 (10)*
C22A0.247 (3)0.91 (2)0.236 (4)0.0465 (10)*
H23A0.41 (2)0.08 (10)0.67 (2)0.0760*
H24A0.46 (3)0.01 (11)0.54 (3)0.0760*
H25A0.27 (2)0.64 (9)0.54 (3)0.0760*
H26A0.32 (2)0.39 (11)0.67 (3)0.0760*
H27A0.46 (2)0.11 (10)0.39 (3)0.0760*
H28A0.27 (2)0.75 (11)0.39 (3)0.0760*
H29A0.49 (2)0.06 (9)0.29 (2)0.0760*
H30A0.54 (2)0.01 (10)0.16 (3)0.0760*
H31A0.49 (2)0.24 (11)0.04 (3)0.0760*
H32A0.39 (3)0.56 (10)0.04 (2)0.0760*
H33A0.32 (2)0.81 (10)0.03 (3)0.0760*
H34A0.22 (2)1.13 (9)0.03 (3)0.0760*
H35A0.18 (2)1.19 (11)0.16 (3)0.0760*
H36A0.23 (2)0.94 (12)0.29 (3)0.0760*
Geometric parameters (Å, º) top
C1—C21.40 (9)C1A—C2A1.40 (8)
C1—C41.40 (9)C1A—C4A1.40 (10)
C2—C61.40 (10)C2A—C6A1.41 (9)
C3—C41.41 (9)C3A—C4A1.39 (9)
C3—C51.41 (8)C3A—C5A1.40 (8)
C5—C61.40 (9)C5A—C6A1.40 (9)
C5—C81.41 (9)C5A—C8A1.40 (9)
C6—C71.41 (8)C6A—C7A1.41 (9)
C7—C101.41 (9)C7A—C10A1.41 (10)
C8—C91.41 (8)C8A—C9A1.40 (9)
C9—C101.41 (8)C9A—C10A1.40 (10)
C9—C171.39 (10)C9A—C17A1.40 (9)
C10—C121.40 (8)C10A—C12A1.42 (7)
C11—C121.41 (10)C11A—C12A1.40 (10)
C11—C161.40 (8)C11A—C16A1.40 (9)
C11—C181.40 (9)C11A—C18A1.40 (10)
C12—C131.40 (10)C12A—C13A1.41 (9)
C13—C141.40 (8)C13A—C14A1.38 (8)
C14—C151.41 (10)C14A—C15A1.40 (10)
C15—C161.39 (9)C15A—C16A1.40 (10)
C17—C181.40 (8)C17A—C18A1.40 (8)
C17—C221.40 (10)C17A—C22A1.38 (11)
C18—C191.41 (10)C18A—C19A1.41 (9)
C19—C201.40 (10)C19A—C20A1.40 (10)
C20—C211.41 (8)C20A—C21A1.40 (9)
C21—C221.40 (10)C21A—C22A1.40 (11)
C1—H231.0 (5)C1A—H23A1.0 (3)
C2—H241.0 (4)C2A—H24A1.0 (5)
C3—H250.9 (5)C3A—H25A1.0 (4)
C4—H260.9 (5)C4A—H26A1.0 (5)
C7—H270.9 (4)C7A—H27A1.0 (4)
C8—H280.9 (6)C8A—H28A0.9 (5)
C13—H290.9 (4)C13A—H29A1.0 (3)
C14—H300.9 (4)C14A—H30A1.0 (4)
C15—H310.9 (3)C15A—H31A0.9 (4)
C16—H321.0 (5)C16A—H32A0.9 (4)
C19—H330.9 (4)C19A—H33A1.0 (4)
C20—H340.9 (5)C20A—H34A1.0 (4)
C21—H351.0 (6)C21A—H35A0.9 (5)
C22—H361.0 (5)C22A—H36A1.0 (5)
C2—C1—C4120 (5)C2A—C1A—C4A120 (5)
C1—C2—C6121 (5)C1A—C2A—C6A119 (6)
C4—C3—C5120 (5)C4A—C3A—C5A120 (6)
C1—C4—C3120 (4)C1A—C4A—C3A120 (5)
C3—C5—C6120 (6)C3A—C5A—C6A120 (6)
C3—C5—C8120 (5)C3A—C5A—C8A120 (6)
C6—C5—C8120 (5)C6A—C5A—C8A120 (5)
C2—C6—C5120 (5)C2A—C6A—C5A121 (5)
C2—C6—C7121 (6)C2A—C6A—C7A120 (6)
C5—C6—C7120 (6)C5A—C6A—C7A120 (6)
C6—C7—C10121 (5)C6A—C7A—C10A120 (6)
C5—C8—C9120 (5)C5A—C8A—C9A120 (6)
C8—C9—C10120 (6)C8A—C9A—C10A120 (6)
C8—C9—C17120 (6)C8A—C9A—C17A119 (6)
C10—C9—C17120 (5)C10A—C9A—C17A120 (5)
C7—C10—C9120 (5)C7A—C10A—C9A120 (5)
C7—C10—C12120 (5)C7A—C10A—C12A120 (6)
C9—C10—C12120 (6)C9A—C10A—C12A120 (6)
C12—C11—C16119 (6)C12A—C11A—C16A120 (7)
C12—C11—C18119 (5)C12A—C11A—C18A120 (5)
C16—C11—C18121 (6)C16A—C11A—C18A120 (6)
C10—C12—C11120 (6)C10A—C12A—C11A120 (6)
C10—C12—C13121 (6)C10A—C12A—C13A120 (6)
C11—C12—C13120 (6)C11A—C12A—C13A120 (5)
C12—C13—C14120 (6)C12A—C13A—C14A120 (6)
C13—C14—C15120 (5)C13A—C14A—C15A121 (6)
C14—C15—C16120 (5)C14A—C15A—C16A120 (6)
C11—C16—C15121 (6)C11A—C16A—C15A120 (6)
C9—C17—C18120 (6)C9A—C17A—C18A120 (6)
C9—C17—C22120 (6)C9A—C17A—C22A120 (5)
C18—C17—C22120 (6)C18A—C17A—C22A121 (6)
C11—C18—C17121 (6)C11A—C18A—C17A121 (6)
C11—C18—C19119 (6)C11A—C18A—C19A120 (6)
C17—C18—C19120 (6)C17A—C18A—C19A120 (6)
C18—C19—C20120 (6)C18A—C19A—C20A119 (5)
C19—C20—C21120 (7)C19A—C20A—C21A121 (6)
C20—C21—C22119 (6)C20A—C21A—C22A119 (7)
C17—C22—C21121 (5)C17A—C22A—C21A120 (6)
C2—C1—H23118C2A—C1A—H23A124
C4—C1—H23121C4A—C1A—H23A116
C1—C2—H24118C1A—C2A—H24A124
C6—C2—H24121C6A—C2A—H24A117
C4—C3—H25119C4A—C3A—H25A117
C5—C3—H25121C5A—C3A—H25A123
C1—C4—H26122C1A—C4A—H26A117
C3—C4—H26118C3A—C4A—H26A123
C6—C7—H27118C6A—C7A—H27A122
C10—C7—H27121C10A—C7A—H27A119
C5—C8—H28119C5A—C8A—H28A117
C9—C8—H28120C9A—C8A—H28A123
C12—C13—H29123C12A—C13A—H29A117
C14—C13—H29117C14A—C13A—H29A123
C13—C14—H30124C13A—C14A—H30A123
C15—C14—H30116C15A—C14A—H30A116
C14—C15—H31121C14A—C15A—H31A116
C16—C15—H31119C16A—C15A—H31A124
C11—C16—H32120C11A—C16A—H32A114
C15—C16—H32118C15A—C16A—H32A126
C18—C19—H33119C18A—C19A—H33A120
C20—C19—H33121C20A—C19A—H33A121
C19—C20—H34118C19A—C20A—H34A120
C21—C20—H34121C21A—C20A—H34A120
C20—C21—H35123C20A—C21A—H35A119
C22—C21—H35118C22A—C21A—H35A122
C17—C22—H36119C17A—C22A—H36A120
C21—C22—H36121C21A—C22A—H36A120
 

Acknowledgements

The authors thank the CCLRC Centre for Molecular Structure and Dynamics for studentship funding for PF and the EPSRC for grant No. GR/N07462/01.

References

First citationAllen, F. H., Johnson, O., Shields, G. P., Smith, B. R. & Towler, M. (2004). J. Appl. Cryst. 37, 335–338.  Web of Science CSD CrossRef CAS IUCr Journals Google Scholar
First citationBoultif, A. & Louer, D. (1991). J. Appl. Cryst. 24, 987–993.  CrossRef CAS Web of Science IUCr Journals Google Scholar
First citationCoelho, A. A. (2003). TOPAS User's Manual. Bruker AXS GmbH, Karlsruhe, Germany.  Google Scholar
First citationDavid, W. I. F., Shankland, K., Cole, J., Maginn, S., Motherwell, W. D. S. & Taylor, R. (2001). DASH. Version 2.1. Cambridge Crystallographic Data Centre, 12 Union Road, Cambridge, England.  Google Scholar
First citationDavid, W. I. F., Shankland, K. & Shankland, N. (1998). Chem. Commun. pp. 931–932.  Web of Science CSD CrossRef Google Scholar
First citationDesiraju, G. R. & Gavezzotti A. (1989). Acta Cryst. B45, 473–482.  CrossRef CAS Web of Science IUCr Journals Google Scholar
First citationDollase, W. A. (1986). J. Appl. Cryst. 19, 267–272.  CrossRef CAS Web of Science IUCr Journals Google Scholar
First citationHill, R. J. & Madsen, I. C. (2002). Structure Determination from Powder Diffraction Data, edited by W. I. F. David, K. Shankland, L. B. McCusker & Ch. Baerlocher, pp. 114–116. Oxford University Press.  Google Scholar
First citationHunter, A. & Sanders, J. K. M. (1990). J. Am. Chem. Soc. 112, 5525–5534.  CrossRef CAS Web of Science Google Scholar
First citationKienle, M. & Jacob, M. (2003). DIFFRAC plus XRD Commander. Version 2.3. Bruker AXS GmbH, Karlsruhe, Germany.  Google Scholar
First citationPawley, G. S. (1981). J. Appl. Cryst. 14, 357–361.  CrossRef CAS Web of Science IUCr Journals Google Scholar
First citationRietveld, H. M. (1969). J. Appl. Cryst. 2, 65–71.  CrossRef CAS IUCr Journals Web of Science Google Scholar
First citationSpek, A. L. (2003). J. Appl. Cryst. 36, 7–13.  Web of Science CrossRef CAS IUCr Journals Google Scholar

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