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ISSN: 2056-9890

Di­phenyl (iso­propyl­amido)­phosphate

aDepartment of Chemistry, Zanjan Branch, Islamic Azad University, Zanjan, Iran, bDepartment of Chemistry, Ferdowsi University of Mashhad, Mashhad, Iran, and cDepartment of Chemistry, Faculty of Science, Masaryk University, Kotlarska 2, Brno CZ-61137, Czech Republic
*Correspondence e-mail: fahimeh_sabbaghi@yahoo.com

(Received 14 November 2012; accepted 21 November 2012; online 28 November 2012)

The P atom in the title compound, C15H18NO3P, is in a distorted tetra­hedral P(O)(O)2N environment; the bond angles at P are in the range 98.16 (6)–115.82 (6)°. In the crystal, adjacent mol­ecules are linked via N—H⋯O=P hydrogen bonds into a chain running parallel to the b axis. The methyl groups are disordered over two sets of sites in a 0.677 (14):0.323 (14) ratio. The crystal studied was a non-merohedral twin with a refined minor component of 22.31 (4)%.

Related literature

For bond lengths and angles in a related structure, see: Sabbaghi et al. (2011[Sabbaghi, F., Pourayoubi, M., Negari, M. & Nečas, M. (2011). Acta Cryst. E67, o2512.]).

[Scheme 1]

Experimental

Crystal data
  • C15H18NO3P

  • Mr = 291.27

  • Monoclinic, P n

  • a = 8.4432 (5) Å

  • b = 5.3030 (4) Å

  • c = 16.3443 (11) Å

  • β = 90.453 (6)°

  • V = 731.78 (9) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.19 mm−1

  • T = 120 K

  • 0.45 × 0.42 × 0.40 mm

Data collection
  • Oxford Diffraction Xcalibur (Sapphire2) diffractometer

  • Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2009[Oxford Diffraction (2009). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Yarnton, England.]) Tmin = 0.918, Tmax = 0.926

  • 6226 measured reflections

  • 6226 independent reflections

  • 6040 reflections with I > 2σ(I)

Refinement
  • R[F2 > 2σ(F2)] = 0.027

  • wR(F2) = 0.081

  • S = 1.06

  • 6226 reflections

  • 208 parameters

  • 28 restraints

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

  • Δρmax = 0.17 e Å−3

  • Δρmin = −0.18 e Å−3

  • Absolute structure: Flack (1983[Flack, H. D. (1983). Acta Cryst. A39, 876-881.]), 1229 Friedel pairs

  • Flack parameter: 0.05 (6)

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H1N⋯O3i 0.81 (1) 2.23 (1) 3.0065 (17) 161 (2)
Symmetry code: (i) x, y+1, z.

Data collection: CrysAlis CCD (Oxford Diffraction, 2009[Oxford Diffraction (2009). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Yarnton, England.]); cell refinement: CrysAlis CCD; data reduction: CrysAlis RED (Oxford Diffraction, 2009[Oxford Diffraction (2009). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Yarnton, England.]); 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: Mercury (Macrae et al., 2008[Macrae, C. F., Bruno, I. J., Chisholm, J. A., Edgington, P. R., McCabe, P., Pidcock, E., Rodriguez-Monge, L., Taylor, R., van de Streek, J. & Wood, P. A. (2008). J. Appl. Cryst. 41, 466-470.]); software used to prepare material for publication: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]) and 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


Comment top

This work is a continuation of our studies of phosphoramidate compounds, during which the structures of various diphenyl amido phosphates, for example [C6H5O]2P(O)[NHCH(C2H5)(C6H5)] (Sabbaghi et al., 2011) were reported. Here, we report the synthesis and crystal structure determination of the title compound, [C6H5O]2P(O)[NHCH(CH3)2].

The PO (1.4602 (11) Å), P—O (1.5858 (11) and 1.5896 (11) Å) and P—N (1.6043 (14) Å) bond lengths are within the expected values (Sabbaghi et al., 2011).

The P atom adopts a distorted tetrahedral configuration (Fig. 1). The bond angles at the P atom vary in the range 98.16 (6) [O1—P1—O2] to 115.82 (6)° [O3—P1—O2].

The C—O—P bond angles (124.07 (10) [C1—O1—P1] and 121.74 (10)° [C7—O2—P1]) and the C13A—N1—P1 (124.19 (11)°) bond angle are standard for this category of phosphoramidate compounds (Sabbaghi et al., 2011).

In the crystal structure, molecules are linked via N—H···OP hydrogen bonds into extended chains running parallel to the b axis (Table 1).

Related literature top

For bond lengths and angles in a related structure, see: Sabbaghi et al. (2011).

Experimental top

To a solution of [C6H5O]2P(O)Cl (2 mmol) in dry CH3CN (30 ml), a solution of isopropylamine (4 mmol) in the same solvent (5 ml) was added at ice bath temperature under stirring. After 4 h, the solvent was removed and the product was washed with distilled water and recrystallized from CH3CN/n-C6H14 (4:1) at room temperature. The single crystals suitable for X-ray analysis were obtained from this solution after a few days at room temperature.

Refinement top

The crystal sample was non-merohedrally twinned. Using data reduction software, a HKLF 5 file was produced for a two-component twin and used in the refinement. The fractional contribution of the minor twin component converged to 0.2231 (4). All carbon bound H atoms were placed at calculated positions and were refined as riding with their Uiso set to either 1.2Ueq or 1.5Ueq (methyl) of the respective carrier atoms; in addition, the methyl H atoms were allowed to rotate about the C—C bond. Nitrogen bound H atom was located in a difference Fourier map and its position was refined while the N—H distance was fixed at 0.88 Å and the Uiso set to 1.2Ueq of N1. The disordered methyl groups were modeled over two sites while restraining their anisotropic displacement parameters to be approximately isotropic (ISOR). To maintain a correct hydrogen geometry, a dummy atom with zero occupancy was created and constrained to share the same site (EXYZ) and anisotropic displacement parameters (EADP) with a fully occupied carbon atom bound to N1.

Computing details top

Data collection: CrysAlis CCD (Oxford Diffraction, 2009); cell refinement: CrysAlis CCD (Oxford Diffraction, 2009); data reduction: CrysAlis RED (Oxford Diffraction, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: Mercury (Macrae et al., 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and enCIFer (Allen et al., 2004).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound with ellipsoids shown at the 50% probability level and H atoms are drawn as small spheres of arbitrary radii. The minor component of disordered part has been omitted for clarity and only one orientation is shown for the disordered part.
Diphenyl (isopropylamido)phosphate top
Crystal data top
C15H18NO3PF(000) = 308
Mr = 291.27Dx = 1.322 Mg m3
Monoclinic, PnMo Kα radiation, λ = 0.71073 Å
a = 8.4432 (5) ÅCell parameters from 3821 reflections
b = 5.3030 (4) Åθ = 3.4–27.5°
c = 16.3443 (11) ŵ = 0.19 mm1
β = 90.453 (6)°T = 120 K
V = 731.78 (9) Å3Block, colourless
Z = 20.45 × 0.42 × 0.40 mm
Data collection top
Oxford Diffraction Xcalibur (Sapphire2)
diffractometer
6226 independent reflections
Radiation source: Enhance (Mo) X-ray Source6040 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.000
Detector resolution: 8.4353 pixels mm-1θmax = 25.0°, θmin = 3.8°
ω scanh = 1010
Absorption correction: multi-scan
(CrysAlis RED; Oxford Diffraction, 2009)
k = 66
Tmin = 0.918, Tmax = 0.926l = 1919
6226 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)] = 0.027H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.081 w = 1/[σ2(Fo2) + (0.0626P)2 + 0.0183P]
where P = (Fo2 + 2Fc2)/3
S = 1.06(Δ/σ)max < 0.001
6226 reflectionsΔρmax = 0.17 e Å3
208 parametersΔρmin = 0.18 e Å3
28 restraintsAbsolute structure: Flack (1983), 1229 Friedel pairs
Primary atom site location: structure-invariant direct methodsAbsolute structure parameter: 0.05 (6)
Crystal data top
C15H18NO3PV = 731.78 (9) Å3
Mr = 291.27Z = 2
Monoclinic, PnMo Kα radiation
a = 8.4432 (5) ŵ = 0.19 mm1
b = 5.3030 (4) ÅT = 120 K
c = 16.3443 (11) Å0.45 × 0.42 × 0.40 mm
β = 90.453 (6)°
Data collection top
Oxford Diffraction Xcalibur (Sapphire2)
diffractometer
6226 independent reflections
Absorption correction: multi-scan
(CrysAlis RED; Oxford Diffraction, 2009)
6040 reflections with I > 2σ(I)
Tmin = 0.918, Tmax = 0.926Rint = 0.000
6226 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.027H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.081Δρmax = 0.17 e Å3
S = 1.06Δρmin = 0.18 e Å3
6226 reflectionsAbsolute structure: Flack (1983), 1229 Friedel pairs
208 parametersAbsolute structure parameter: 0.05 (6)
28 restraints
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*/UeqOcc. (<1)
P10.49359 (4)0.20465 (6)0.51025 (3)0.01893 (9)
O10.46890 (12)0.20756 (19)0.41396 (6)0.0229 (3)
O20.32869 (12)0.3259 (2)0.53519 (6)0.0213 (2)
O30.52704 (12)0.04455 (19)0.54422 (6)0.0247 (3)
N10.62616 (15)0.4126 (2)0.53057 (8)0.0201 (3)
H1N0.603 (2)0.559 (3)0.5224 (10)0.024*
C10.33996 (19)0.0959 (3)0.37348 (10)0.0241 (4)
C20.2687 (2)0.1207 (3)0.40086 (13)0.0346 (4)
H20.30360.20170.44960.042*
C30.1433 (2)0.2176 (3)0.35464 (15)0.0454 (6)
H30.09150.36630.37270.054*
C40.0931 (2)0.1044 (4)0.28402 (14)0.0489 (6)
H40.00660.17250.25370.059*
C50.1686 (2)0.1079 (4)0.25735 (13)0.0440 (5)
H50.13590.18480.20750.053*
C60.2921 (2)0.2121 (3)0.30207 (11)0.0307 (4)
H60.34300.36140.28380.037*
C70.27851 (18)0.3331 (3)0.61695 (10)0.0197 (4)
C80.31935 (19)0.5376 (3)0.66473 (9)0.0244 (4)
H80.38680.66560.64410.029*
C90.2607 (2)0.5528 (3)0.74285 (10)0.0319 (4)
H90.28740.69280.77650.038*
C100.1630 (2)0.3656 (4)0.77258 (11)0.0376 (5)
H100.12320.37630.82670.045*
C110.1238 (2)0.1643 (3)0.72383 (12)0.0360 (5)
H110.05620.03610.74430.043*
C120.1817 (2)0.1460 (3)0.64507 (12)0.0306 (4)
H120.15470.00650.61130.037*
C13A0.79551 (19)0.3558 (3)0.54259 (10)0.0212 (4)
H13A0.80170.19110.57220.025*0.323 (14)
C14A0.8579 (13)0.557 (2)0.6011 (9)0.042 (3)0.323 (14)
H14A0.84010.72420.57730.064*0.323 (14)
H14B0.97160.53120.61040.064*0.323 (14)
H14C0.80210.54440.65330.064*0.323 (14)
C15A0.8791 (19)0.324 (3)0.4671 (9)0.037 (3)0.323 (14)
H15A0.83070.18690.43550.056*0.323 (14)
H15B0.99020.28330.47880.056*0.323 (14)
H15C0.87360.48080.43540.056*0.323 (14)
C13B0.79551 (19)0.3558 (3)0.54259 (10)0.0212 (4)0.00
H13B0.80850.23010.58780.025*0.677 (14)
C14B0.8824 (4)0.5997 (8)0.5652 (4)0.0306 (11)0.677 (14)
H14D0.86330.72670.52270.046*0.677 (14)
H14E0.99630.56620.56960.046*0.677 (14)
H14F0.84340.66220.61770.046*0.677 (14)
C15B0.8680 (8)0.2476 (13)0.4620 (4)0.0298 (11)0.677 (14)
H15D0.81600.08770.44820.045*0.677 (14)
H15E0.98180.21880.47010.045*0.677 (14)
H15F0.85170.36830.41740.045*0.677 (14)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
P10.01606 (19)0.01911 (19)0.02163 (19)0.00093 (19)0.00011 (14)0.0017 (2)
O10.0195 (6)0.0253 (6)0.0238 (6)0.0048 (5)0.0003 (5)0.0003 (5)
O20.0173 (6)0.0247 (6)0.0218 (6)0.0019 (5)0.0019 (4)0.0017 (5)
O30.0239 (6)0.0191 (6)0.0313 (6)0.0014 (4)0.0029 (5)0.0024 (5)
N10.0184 (7)0.0154 (7)0.0265 (8)0.0024 (5)0.0008 (5)0.0027 (6)
C10.0155 (8)0.0276 (9)0.0291 (10)0.0002 (7)0.0017 (7)0.0118 (7)
C20.0318 (11)0.0258 (9)0.0462 (12)0.0045 (8)0.0004 (8)0.0038 (9)
C30.0349 (12)0.0286 (11)0.0727 (17)0.0092 (9)0.0004 (11)0.0148 (11)
C40.0245 (11)0.0615 (14)0.0604 (15)0.0062 (10)0.0054 (10)0.0292 (11)
C50.0239 (11)0.0722 (16)0.0359 (12)0.0046 (10)0.0064 (8)0.0101 (11)
C60.0207 (10)0.0402 (11)0.0313 (10)0.0021 (8)0.0023 (8)0.0036 (9)
C70.0137 (9)0.0204 (8)0.0251 (9)0.0058 (6)0.0003 (7)0.0059 (7)
C80.0262 (10)0.0223 (8)0.0248 (9)0.0025 (7)0.0027 (7)0.0031 (7)
C90.0431 (12)0.0242 (10)0.0284 (10)0.0084 (9)0.0014 (8)0.0006 (8)
C100.0368 (12)0.0450 (12)0.0312 (10)0.0186 (9)0.0138 (9)0.0091 (9)
C110.0289 (11)0.0336 (11)0.0457 (13)0.0015 (8)0.0162 (9)0.0143 (9)
C120.0237 (10)0.0255 (9)0.0427 (11)0.0001 (7)0.0052 (8)0.0003 (8)
C13A0.0166 (9)0.0217 (8)0.0253 (9)0.0034 (6)0.0049 (7)0.0023 (7)
C14A0.033 (4)0.043 (4)0.051 (4)0.008 (3)0.019 (3)0.007 (3)
C15A0.030 (4)0.038 (5)0.043 (4)0.010 (4)0.006 (3)0.011 (4)
C13B0.0166 (9)0.0217 (8)0.0253 (9)0.0034 (6)0.0049 (7)0.0023 (7)
C14B0.0200 (15)0.0309 (18)0.041 (2)0.0000 (12)0.0056 (15)0.0077 (16)
C15B0.0230 (18)0.035 (3)0.0317 (19)0.0010 (19)0.0069 (14)0.007 (2)
Geometric parameters (Å, º) top
P1—O31.4602 (11)C9—C101.381 (3)
P1—O11.5858 (11)C9—H90.9500
P1—O21.5896 (11)C10—C111.371 (3)
P1—N11.6043 (14)C10—H100.9500
O1—C11.4008 (19)C11—C121.384 (2)
O2—C71.4057 (17)C11—H110.9500
N1—C13A1.4728 (19)C12—H120.9500
N1—H1N0.811 (13)C13A—C15A1.436 (15)
C1—C21.373 (2)C13A—C14A1.524 (8)
C1—C61.378 (2)C13A—H13A1.0000
C2—C31.393 (3)C14A—H14A0.9800
C2—H20.9500C14A—H14B0.9800
C3—C41.366 (3)C14A—H14C0.9800
C3—H30.9500C15A—H15A0.9800
C4—C51.367 (3)C15A—H15B0.9800
C4—H40.9500C15A—H15C0.9800
C5—C61.383 (3)C14B—H14D0.9800
C5—H50.9500C14B—H14E0.9800
C6—H60.9500C14B—H14F0.9800
C7—C121.367 (2)C15B—H15D0.9800
C7—C81.379 (2)C15B—H15E0.9800
C8—C91.376 (2)C15B—H15F0.9800
C8—H80.9500
O3—P1—O1114.19 (6)C12—C7—O2119.04 (14)
O3—P1—O2115.82 (6)C8—C7—O2118.95 (13)
O1—P1—O298.16 (6)C9—C8—C7118.79 (15)
O3—P1—N1114.26 (7)C9—C8—H8120.6
O1—P1—N1106.55 (6)C7—C8—H8120.6
O2—P1—N1106.26 (6)C8—C9—C10120.31 (17)
C1—O1—P1124.07 (10)C8—C9—H9119.8
C7—O2—P1121.74 (10)C10—C9—H9119.8
C13A—N1—P1124.19 (11)C11—C10—C9119.82 (16)
C13A—N1—H1N116.9 (13)C11—C10—H10120.1
P1—N1—H1N117.1 (13)C9—C10—H10120.1
C2—C1—C6121.57 (16)C10—C11—C12120.63 (15)
C2—C1—O1122.74 (15)C10—C11—H11119.7
C6—C1—O1115.65 (14)C12—C11—H11119.7
C1—C2—C3117.70 (19)C7—C12—C11118.59 (17)
C1—C2—H2121.2C7—C12—H12120.7
C3—C2—H2121.2C11—C12—H12120.7
C4—C3—C2121.69 (19)C15A—C13A—N1113.1 (7)
C4—C3—H3119.2C15A—C13A—C14A116.8 (6)
C2—C3—H3119.2N1—C13A—C14A105.7 (4)
C3—C4—C5119.3 (2)C15A—C13A—H13A106.9
C3—C4—H4120.4N1—C13A—H13A106.9
C5—C4—H4120.4C14A—C13A—H13A106.9
C4—C5—C6120.8 (2)H14D—C14B—H14E109.5
C4—C5—H5119.6H14D—C14B—H14F109.5
C6—C5—H5119.6H14E—C14B—H14F109.5
C1—C6—C5118.93 (17)H15D—C15B—H15E109.5
C1—C6—H6120.5H15D—C15B—H15F109.5
C5—C6—H6120.5H15E—C15B—H15F109.5
C12—C7—C8121.86 (15)
O3—P1—O1—C167.82 (12)C2—C1—C6—C50.3 (3)
O2—P1—O1—C155.32 (12)O1—C1—C6—C5177.98 (15)
N1—P1—O1—C1165.06 (11)C4—C5—C6—C11.1 (3)
O3—P1—O2—C748.50 (13)P1—O2—C7—C1295.01 (17)
O1—P1—O2—C7170.46 (11)P1—O2—C7—C889.47 (14)
N1—P1—O2—C779.57 (12)C12—C7—C8—C90.0 (2)
O3—P1—N1—C13A30.26 (15)O2—C7—C8—C9175.40 (15)
O1—P1—N1—C13A96.81 (13)C7—C8—C9—C100.2 (3)
O2—P1—N1—C13A159.24 (12)C8—C9—C10—C110.4 (3)
P1—O1—C1—C233.7 (2)C9—C10—C11—C120.3 (3)
P1—O1—C1—C6148.68 (12)C8—C7—C12—C110.1 (3)
C6—C1—C2—C31.2 (3)O2—C7—C12—C11175.45 (15)
O1—C1—C2—C3178.68 (16)C10—C11—C12—C70.1 (3)
C1—C2—C3—C40.7 (3)P1—N1—C13A—C15A80.0 (6)
C2—C3—C4—C50.7 (3)P1—N1—C13A—C14A150.9 (7)
C3—C4—C5—C61.7 (3)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1N···O3i0.81 (1)2.23 (1)3.0065 (17)161 (2)
Symmetry code: (i) x, y+1, z.

Experimental details

Crystal data
Chemical formulaC15H18NO3P
Mr291.27
Crystal system, space groupMonoclinic, Pn
Temperature (K)120
a, b, c (Å)8.4432 (5), 5.3030 (4), 16.3443 (11)
β (°) 90.453 (6)
V3)731.78 (9)
Z2
Radiation typeMo Kα
µ (mm1)0.19
Crystal size (mm)0.45 × 0.42 × 0.40
Data collection
DiffractometerOxford Diffraction Xcalibur (Sapphire2)
diffractometer
Absorption correctionMulti-scan
(CrysAlis RED; Oxford Diffraction, 2009)
Tmin, Tmax0.918, 0.926
No. of measured, independent and
observed [I > 2σ(I)] reflections
6226, 6226, 6040
Rint0.000
(sin θ/λ)max1)0.595
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.027, 0.081, 1.06
No. of reflections6226
No. of parameters208
No. of restraints28
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.17, 0.18
Absolute structureFlack (1983), 1229 Friedel pairs
Absolute structure parameter0.05 (6)

Computer programs: CrysAlis CCD (Oxford Diffraction, 2009), CrysAlis RED (Oxford Diffraction, 2009), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), Mercury (Macrae et al., 2008), SHELXTL (Sheldrick, 2008) and enCIFer (Allen et al., 2004).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1N···O3i0.811 (13)2.228 (13)3.0065 (17)161.0 (15)
Symmetry code: (i) x, y+1, z.
 

Acknowledgements

Support of this investigation by Zanjan Branch, Islamic Azad University, is gratefully acknowledged.

References

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First citationFlack, H. D. (1983). Acta Cryst. A39, 876–881.  CrossRef CAS Web of Science IUCr Journals
First citationMacrae, C. F., Bruno, I. J., Chisholm, J. A., Edgington, P. R., McCabe, P., Pidcock, E., Rodriguez-Monge, L., Taylor, R., van de Streek, J. & Wood, P. A. (2008). J. Appl. Cryst. 41, 466–470.  Web of Science CrossRef CAS IUCr Journals
First citationOxford Diffraction (2009). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Yarnton, England.
First citationSabbaghi, F., Pourayoubi, M., Negari, M. & Nečas, M. (2011). Acta Cryst. E67, o2512.  Web of Science CSD CrossRef IUCr Journals
First citationSheldrick, G. M. (2008). Acta Cryst. A64, 112–122.  Web of Science CrossRef CAS IUCr Journals

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