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ISSN: 2056-9890

Bis(4-nitro­phen­yl) 1,3-phenyl­ene­di­methyl­ene dicarbonate

aHEJ Research Institute of Chemistry, International Center for Chemical Sciences, University of Karachi, Karachi 75270, Pakistan, and bDepartment of Chemistry, University of Toronto, Toronto, Ontario, Canada M5S 3H6
*Correspondence e-mail: alough@chem.utoronto.ca

(Received 20 February 2008; accepted 5 March 2008; online 12 March 2008)

In the title mol­ecule, C22H16N2O10, the dihedral angles between the benzene rings of the 4-nitro­phenyl groups and the central benzene ring are 32.7 (1) and 34.7 (1)°, while the dihedral angle between the two benzene rings of the 4-nitro­phenyl groups is 3.6 (2)°. In the crystal structure, weak inter­molecular C—H⋯O hydrogen bonds link mol­ecules into centrosymmetric dimers.

Related literature

For related literature, see: Nawazish Ali et al. (2008[Nawazish Ali, S., Begum, S., Winnik, M. A. & Lough, A. J. (2008). Acta Cryst. E64, o281.]).

[Scheme 1]

Experimental

Crystal data
  • C22H16N2O10

  • Mr = 468.37

  • Triclinic, [P \overline 1]

  • a = 8.5956 (4) Å

  • b = 9.2367 (5) Å

  • c = 14.1550 (8) Å

  • α = 94.094 (2)°

  • β = 107.134 (3)°

  • γ = 105.674 (3)°

  • V = 1020.00 (10) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.12 mm−1

  • T = 150 (1) K

  • 0.34 × 0.20 × 0.20 mm

Data collection
  • Bruker–Nonius KappaCCD diffractometer

  • Absorption correction: multi-scan (SORTAV; Blessing, 1995[Blessing, R. H. (1995). Acta Cryst. A51, 33-38.]) Tmin = 0.808, Tmax = 0.980

  • 10107 measured reflections

  • 4580 independent reflections

  • 3182 reflections with I > 2σ(I)

  • Rint = 0.054

Refinement
  • R[F2 > 2σ(F2)] = 0.064

  • wR(F2) = 0.166

  • S = 1.15

  • 4580 reflections

  • 308 parameters

  • H-atom parameters constrained

  • Δρmax = 0.30 e Å−3

  • Δρmin = −0.26 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C10—H10A⋯O10i 0.95 2.55 3.134 (4) 120
C15—H15B⋯O9i 0.99 2.58 3.504 (4) 155
C21—H21A⋯O7i 0.95 2.50 3.264 (3) 138
Symmetry code: (i) -x+1, -y+1, -z+2.

Data collection: COLLECT (Nonius, 2002[Nonius (2002). COLLECT. Nonius BV, Delft, The Netherlands.]); cell refinement: DENZO–SMN (Otwinowski & Minor, 1997[Otwinowski, Z. & Minor, W. (1997). Methods in Enzymology, Vol. 276, Macromolecular Crystallography, Part A, edited by C. W. Carter Jr & R. M. Sweet, pp. 307-326. New York: Academic Press.]); data reduction: DENZO–SMN; program(s) used to solve structure: SIR92 (Altomare et al., 1994[Altomare, A., Cascarano, G., Giacovazzo, C., Guagliardi, A., Burla, M. C., Polidori, G. & Camalli, M. (1994). J. Appl. Cryst. 27, 435.]); program(s) used to refine structure: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.

Supporting information


Comment top

For background information and relevant references see Ali et al. (2008). In the title molecule (Fig. 1) the dihedral angles between the benzene rings of the p-nitrophenyl groups and the central benzene ring are 32.7 (1) (for C9—C14) and 34.7 (1)° (for C17—C22), while the dihedral angle between the two benzene rings of the p-nitrophenyl groups is 3.6 (2)°. In the crystal structure, weak intermolecluar C—H···O hydrogen bonds link molecules into centrosymmetric dimers (Fig. 2).

Related literature top

For related literature, see: Nawazish Ali et al. (2008).

Experimental top

A solution of 4-nitrophenylchloroformate (14.1 g, 70 mmol) in dry dichloromethane (70 ml) was added dropwise via a 250 ml separatory funnel to a solution of 1,3-phenylenedimethanol (4.82 g, 35 mmol) in anhydrous pyridine (5.38 g, 5.5 ml, 68.0 mmol) and dry dichloromethane (20 ml) in a 250 ml round-bottom flask. A white suspension appeared which was stirred gently at room temperature for 10 h. After this time more dry dichloromethane (50 ml) was added, which dissolved the suspension and then the reaction mixture was stirred for another 6 h. It was then quenched by adding deionized water (50 ml). The reaction mixture was transferred to a separatory funnel (500 ml), and the lower organic phase was removed. The aqueous phase was washed with dichloromethane (30 ml x 3), and all the dichloromethane solutions were combined. These were then washed with deionized water (40 ml x 3), a 1.0% solution of acetic acid (50 ml x 4) and once more with deionized water (40 ml x 3), and then dried over anhydrous magnesium sulfate and filtered. After filtration, the solvent was removed by rotary evaporator. The product was dried in air overnight in a fume hood and then in a vacuum oven for 24 h at room temperature (< 1 Torr). The desired product was obtained in a moderate yield (11.4 g, 70.0%) as a white solid; the product was recrystallized by dissolving in a mixture of dichloromethane and ethanol (95%) (1:1). The reaction mixture was heated at 358 K, and filtered after 40 minutes. X-ray quality crystals were obtained after slow evaporation of the solvent at room temperature.

Refinement top

Hydrogen atoms were placed in calculated positions with C—H = 0.95–1.00 Å and they were included in the refinement in the riding-model approximation with Uiso(H) = 1.2Ueq(C).

Computing details top

Data collection: COLLECT (Nonius, 2002); cell refinement: DENZO–SMN (Otwinowski & Minor, 1997); data reduction: DENZO–SMN (Otwinowski & Minor, 1997); program(s) used to solve structure: SIR92 (Altomare et al., 1994); 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. The molecular structure of the title compound showing displacement ellipsoids drawn at the 30% probability level.
[Figure 2] Fig. 2. Part of the crystal structure with weak intermolecular C—H···O hydrogen bonds shown as dashed lines.
Bis(4-nitrophenyl) 1,3-phenylenedimethylene dicarbonate top
Crystal data top
C22H16N2O10Z = 2
Mr = 468.37F(000) = 484
Triclinic, P1Dx = 1.525 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 8.5956 (4) ÅCell parameters from 10107 reflections
b = 9.2367 (5) Åθ = 2.6–27.5°
c = 14.1550 (8) ŵ = 0.12 mm1
α = 94.094 (2)°T = 150 K
β = 107.134 (3)°Block, colourless
γ = 105.674 (3)°0.34 × 0.20 × 0.20 mm
V = 1020.00 (10) Å3
Data collection top
Bruker–Nonius KappaCCD
diffractometer
4580 independent reflections
Radiation source: fine-focus sealed tube3182 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.054
Detector resolution: 9 pixels mm-1θmax = 27.5°, θmin = 2.6°
ϕ scans and ω scans with κ offsetsh = 1110
Absorption correction: multi-scan
(SORTAV; Blessing, 1995)
k = 1111
Tmin = 0.808, Tmax = 0.980l = 1818
10107 measured reflections
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)] = 0.064H-atom parameters constrained
wR(F2) = 0.166 w = 1/[σ2(Fo2) + (0.035P)2 + 1.3721P]
where P = (Fo2 + 2Fc2)/3
S = 1.15(Δ/σ)max < 0.001
4580 reflectionsΔρmax = 0.30 e Å3
308 parametersΔρmin = 0.26 e Å3
0 restraintsExtinction correction: SHELXTL (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.021 (4)
Crystal data top
C22H16N2O10γ = 105.674 (3)°
Mr = 468.37V = 1020.00 (10) Å3
Triclinic, P1Z = 2
a = 8.5956 (4) ÅMo Kα radiation
b = 9.2367 (5) ŵ = 0.12 mm1
c = 14.1550 (8) ÅT = 150 K
α = 94.094 (2)°0.34 × 0.20 × 0.20 mm
β = 107.134 (3)°
Data collection top
Bruker–Nonius KappaCCD
diffractometer
4580 independent reflections
Absorption correction: multi-scan
(SORTAV; Blessing, 1995)
3182 reflections with I > 2σ(I)
Tmin = 0.808, Tmax = 0.980Rint = 0.054
10107 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0640 restraints
wR(F2) = 0.166H-atom parameters constrained
S = 1.15Δρmax = 0.30 e Å3
4580 reflectionsΔρmin = 0.26 e Å3
308 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
O10.8872 (3)0.1353 (2)0.51451 (16)0.0340 (5)
O20.6463 (3)0.2045 (3)0.48906 (18)0.0406 (6)
O30.8682 (3)0.3232 (2)0.43660 (16)0.0339 (5)
O40.5734 (3)0.8621 (3)0.32218 (18)0.0493 (7)
O50.5700 (3)0.7631 (3)0.17823 (17)0.0453 (6)
O60.7702 (3)0.1855 (2)0.94414 (15)0.0321 (5)
O70.7572 (3)0.4000 (2)1.02591 (16)0.0346 (5)
O80.6017 (3)0.1596 (2)1.03074 (15)0.0304 (5)
O90.1915 (5)0.4431 (4)1.2504 (3)0.0781 (10)
O100.2930 (3)0.3121 (3)1.35819 (18)0.0490 (7)
N10.6000 (3)0.7673 (3)0.26870 (19)0.0343 (6)
N20.2722 (4)0.3547 (3)1.2770 (2)0.0413 (7)
C10.8609 (4)0.1437 (3)0.7314 (2)0.0289 (6)
H1A0.78260.19490.69960.035*
C20.9034 (4)0.0426 (3)0.6733 (2)0.0269 (6)
C31.0188 (4)0.0314 (4)0.7203 (2)0.0326 (7)
H3A1.05050.09930.68140.039*
C41.0875 (4)0.0059 (4)0.8237 (2)0.0388 (8)
H4A1.16580.05710.85560.047*
C51.0431 (4)0.0932 (4)0.8811 (2)0.0363 (7)
H5A1.08930.10820.95210.044*
C60.9314 (4)0.1712 (3)0.8356 (2)0.0313 (7)
C70.8208 (4)0.0058 (3)0.5615 (2)0.0333 (7)
H7A0.84430.08540.53540.040*
H7B0.69540.01730.54440.040*
C80.7845 (4)0.2182 (3)0.4820 (2)0.0300 (6)
C90.7965 (4)0.4351 (3)0.3983 (2)0.0288 (6)
C100.7170 (4)0.5092 (3)0.4481 (2)0.0311 (7)
H10A0.70520.48390.51000.037*
C110.6548 (4)0.6215 (3)0.4058 (2)0.0314 (7)
H11A0.60080.67580.43870.038*
C120.6728 (4)0.6530 (3)0.3153 (2)0.0287 (6)
C130.7562 (4)0.5817 (4)0.2664 (2)0.0320 (7)
H13A0.76910.60800.20490.038*
C140.8204 (4)0.4712 (3)0.3092 (2)0.0310 (7)
H14A0.87990.42080.27810.037*
C150.8850 (4)0.2793 (4)0.8979 (3)0.0382 (8)
H15A0.98870.34770.95010.046*
H15B0.82670.34240.85560.046*
C160.7147 (4)0.2644 (3)1.0016 (2)0.0269 (6)
C170.5156 (4)0.2113 (3)1.0894 (2)0.0261 (6)
C180.5105 (4)0.1426 (3)1.1723 (2)0.0284 (6)
H18A0.56210.06421.18650.034*
C190.4293 (4)0.1892 (3)1.2346 (2)0.0295 (6)
H19A0.42710.14611.29330.035*
C200.3518 (4)0.2999 (3)1.2088 (2)0.0294 (6)
C210.3483 (4)0.3636 (3)1.1233 (2)0.0312 (7)
H21A0.28980.43681.10670.037*
C220.4322 (4)0.3182 (3)1.0620 (2)0.0279 (6)
H22A0.43230.35971.00250.033*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0368 (12)0.0373 (12)0.0328 (11)0.0141 (10)0.0145 (10)0.0116 (9)
O20.0349 (13)0.0401 (13)0.0535 (15)0.0122 (10)0.0215 (11)0.0171 (11)
O30.0352 (12)0.0365 (12)0.0347 (12)0.0114 (10)0.0163 (10)0.0116 (10)
O40.0688 (18)0.0461 (15)0.0451 (14)0.0304 (14)0.0230 (13)0.0126 (12)
O50.0525 (15)0.0504 (15)0.0315 (12)0.0159 (12)0.0094 (11)0.0155 (11)
O60.0388 (12)0.0276 (11)0.0331 (11)0.0059 (9)0.0210 (10)0.0018 (9)
O70.0409 (12)0.0249 (12)0.0371 (12)0.0039 (9)0.0185 (10)0.0001 (9)
O80.0381 (12)0.0240 (11)0.0351 (11)0.0082 (9)0.0217 (10)0.0060 (9)
O90.110 (3)0.081 (2)0.102 (3)0.070 (2)0.078 (2)0.0417 (19)
O100.0583 (16)0.0476 (15)0.0417 (14)0.0040 (12)0.0308 (13)0.0023 (11)
N10.0335 (14)0.0357 (15)0.0321 (14)0.0068 (12)0.0105 (12)0.0111 (12)
N20.0466 (17)0.0318 (15)0.0512 (18)0.0068 (13)0.0302 (15)0.0010 (13)
C10.0275 (15)0.0283 (15)0.0332 (16)0.0083 (12)0.0135 (13)0.0064 (13)
C20.0259 (15)0.0261 (15)0.0294 (15)0.0060 (12)0.0114 (12)0.0056 (12)
C30.0328 (16)0.0361 (17)0.0366 (17)0.0152 (14)0.0180 (14)0.0077 (14)
C40.0333 (17)0.050 (2)0.0390 (18)0.0189 (16)0.0137 (15)0.0152 (16)
C50.0319 (16)0.047 (2)0.0261 (15)0.0045 (15)0.0105 (13)0.0049 (14)
C60.0306 (16)0.0287 (16)0.0349 (16)0.0022 (13)0.0182 (14)0.0026 (13)
C70.0425 (18)0.0285 (16)0.0299 (16)0.0112 (14)0.0127 (14)0.0058 (13)
C80.0357 (17)0.0294 (16)0.0235 (14)0.0092 (13)0.0087 (13)0.0034 (12)
C90.0308 (15)0.0265 (15)0.0260 (14)0.0053 (12)0.0076 (12)0.0051 (12)
C100.0377 (17)0.0299 (16)0.0229 (14)0.0059 (13)0.0103 (13)0.0022 (12)
C110.0341 (16)0.0290 (16)0.0280 (15)0.0048 (13)0.0106 (13)0.0017 (12)
C120.0284 (15)0.0261 (15)0.0265 (15)0.0031 (12)0.0059 (12)0.0051 (12)
C130.0312 (16)0.0350 (17)0.0256 (15)0.0014 (13)0.0108 (13)0.0068 (13)
C140.0279 (15)0.0330 (17)0.0302 (15)0.0047 (13)0.0113 (13)0.0041 (13)
C150.0449 (19)0.0300 (17)0.0402 (18)0.0003 (14)0.0262 (16)0.0001 (14)
C160.0280 (15)0.0261 (16)0.0242 (14)0.0051 (12)0.0085 (12)0.0025 (12)
C170.0284 (15)0.0236 (14)0.0251 (14)0.0046 (12)0.0112 (12)0.0005 (11)
C180.0316 (16)0.0245 (15)0.0301 (15)0.0077 (12)0.0118 (13)0.0067 (12)
C190.0314 (16)0.0290 (16)0.0276 (15)0.0038 (13)0.0132 (13)0.0067 (12)
C200.0299 (15)0.0250 (15)0.0330 (16)0.0028 (12)0.0164 (13)0.0021 (12)
C210.0288 (15)0.0277 (16)0.0362 (17)0.0088 (13)0.0097 (13)0.0032 (13)
C220.0300 (15)0.0277 (15)0.0229 (14)0.0067 (12)0.0063 (12)0.0037 (12)
Geometric parameters (Å, º) top
O1—C81.324 (4)C5—H5A0.950
O1—C71.472 (4)C6—C151.494 (4)
O2—C81.195 (4)C7—H7A0.990
O3—C81.362 (3)C7—H7B0.990
O3—C91.404 (3)C9—C101.379 (4)
O4—N11.227 (3)C9—C141.385 (4)
O5—N11.225 (3)C10—C111.385 (4)
O6—C161.323 (3)C10—H10A0.950
O6—C151.467 (3)C11—C121.377 (4)
O7—C161.199 (3)C11—H11A0.950
O8—C161.355 (3)C12—C131.382 (4)
O8—C171.400 (3)C13—C141.382 (4)
O9—N21.219 (4)C13—H13A0.950
O10—N21.220 (4)C14—H14A0.950
N1—C121.468 (4)C15—H15A0.990
N2—C201.471 (4)C15—H15B0.990
C1—C21.391 (4)C17—C181.380 (4)
C1—C61.394 (4)C17—C221.383 (4)
C1—H1A0.950C18—C191.386 (4)
C2—C31.392 (4)C18—H18A0.950
C2—C71.501 (4)C19—C201.379 (4)
C3—C41.384 (4)C19—H19A0.950
C3—H3A0.950C20—C211.378 (4)
C4—C51.381 (4)C21—C221.389 (4)
C4—H4A0.950C21—H21A0.950
C5—C61.390 (4)C22—H22A0.950
C8—O1—C7116.3 (2)C9—C10—H10A120.7
C8—O3—C9119.8 (2)C11—C10—H10A120.7
C16—O6—C15114.3 (2)C12—C11—C10118.7 (3)
C16—O8—C17118.4 (2)C12—C11—H11A120.7
O5—N1—O4123.6 (3)C10—C11—H11A120.7
O5—N1—C12117.9 (3)C11—C12—C13122.9 (3)
O4—N1—C12118.5 (2)C11—C12—N1118.5 (3)
O9—N2—O10123.2 (3)C13—C12—N1118.6 (3)
O9—N2—C20118.2 (3)C12—C13—C14118.4 (3)
O10—N2—C20118.6 (3)C12—C13—H13A120.8
C2—C1—C6121.0 (3)C14—C13—H13A120.8
C2—C1—H1A119.5C13—C14—C9118.8 (3)
C6—C1—H1A119.5C13—C14—H14A120.6
C1—C2—C3119.2 (3)C9—C14—H14A120.6
C1—C2—C7121.4 (3)O6—C15—C6106.4 (2)
C3—C2—C7119.3 (3)O6—C15—H15A110.4
C4—C3—C2119.9 (3)C6—C15—H15A110.4
C4—C3—H3A120.0O6—C15—H15B110.4
C2—C3—H3A120.0C6—C15—H15B110.4
C5—C4—C3120.6 (3)H15A—C15—H15B108.6
C5—C4—H4A119.7O7—C16—O6128.0 (3)
C3—C4—H4A119.7O7—C16—O8126.2 (3)
C4—C5—C6120.4 (3)O6—C16—O8105.7 (2)
C4—C5—H5A119.8C18—C17—C22122.3 (3)
C6—C5—H5A119.8C18—C17—O8116.0 (2)
C5—C6—C1118.8 (3)C22—C17—O8121.6 (2)
C5—C6—C15120.2 (3)C17—C18—C19119.2 (3)
C1—C6—C15120.9 (3)C17—C18—H18A120.4
O1—C7—C2110.4 (2)C19—C18—H18A120.4
O1—C7—H7A109.6C20—C19—C18118.0 (3)
C2—C7—H7A109.6C20—C19—H19A121.0
O1—C7—H7B109.6C18—C19—H19A121.0
C2—C7—H7B109.6C21—C20—C19123.2 (3)
H7A—C7—H7B108.1C21—C20—N2118.6 (3)
O2—C8—O1128.1 (3)C19—C20—N2118.2 (3)
O2—C8—O3126.4 (3)C20—C21—C22118.5 (3)
O1—C8—O3105.5 (2)C20—C21—H21A120.8
C10—C9—C14122.6 (3)C22—C21—H21A120.8
C10—C9—O3122.7 (3)C17—C22—C21118.6 (3)
C14—C9—O3114.6 (3)C17—C22—H22A120.7
C9—C10—C11118.5 (3)C21—C22—H22A120.7
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C10—H10A···O10i0.952.553.134 (4)120
C15—H15B···O9i0.992.583.504 (4)155
C21—H21A···O7i0.952.503.264 (3)138
Symmetry code: (i) x+1, y+1, z+2.

Experimental details

Crystal data
Chemical formulaC22H16N2O10
Mr468.37
Crystal system, space groupTriclinic, P1
Temperature (K)150
a, b, c (Å)8.5956 (4), 9.2367 (5), 14.1550 (8)
α, β, γ (°)94.094 (2), 107.134 (3), 105.674 (3)
V3)1020.00 (10)
Z2
Radiation typeMo Kα
µ (mm1)0.12
Crystal size (mm)0.34 × 0.20 × 0.20
Data collection
DiffractometerBruker–Nonius KappaCCD
diffractometer
Absorption correctionMulti-scan
(SORTAV; Blessing, 1995)
Tmin, Tmax0.808, 0.980
No. of measured, independent and
observed [I > 2σ(I)] reflections
10107, 4580, 3182
Rint0.054
(sin θ/λ)max1)0.649
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.064, 0.166, 1.15
No. of reflections4580
No. of parameters308
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.30, 0.26

Computer programs: COLLECT (Nonius, 2002), DENZO–SMN (Otwinowski & Minor, 1997), SIR92 (Altomare et al., 1994), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C10—H10A···O10i0.952.553.134 (4)120
C15—H15B···O9i0.992.583.504 (4)155
C21—H21A···O7i0.952.503.264 (3)138
Symmetry code: (i) x+1, y+1, z+2.
 

Acknowledgements

The authors acknowledge the Higher Education Commission (HEC) of Pakistan, Materials and Manufacturing Ontario (MMO), Canada, NSERC Canada and the University of Toronto for funding.

References

First citationNawazish Ali, S., Begum, S., Winnik, M. A. & Lough, A. J. (2008). Acta Cryst. E64, o281.  Web of Science CrossRef IUCr Journals Google Scholar
First citationAltomare, A., Cascarano, G., Giacovazzo, C., Guagliardi, A., Burla, M. C., Polidori, G. & Camalli, M. (1994). J. Appl. Cryst. 27, 435.  CrossRef Web of Science IUCr Journals Google Scholar
First citationBlessing, R. H. (1995). Acta Cryst. A51, 33–38.  CrossRef CAS Web of Science IUCr Journals Google Scholar
First citationNonius (2002). COLLECT. Nonius BV, Delft, The Netherlands.  Google Scholar
First citationOtwinowski, Z. & Minor, W. (1997). Methods in Enzymology, Vol. 276, Macromolecular Crystallography, Part A, edited by C. W. Carter Jr & R. M. Sweet, pp. 307–326. New York: Academic Press.  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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