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organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 67| Part 7| July 2011| Page o1713
doi:10.1107/S160053681102294X

7-Di­ethyl­amino-2-oxo-2H-chromene-3-carbaldehyde

Hong-Da Lia and Bing-Zhu Yina*

aKey Laboratory of Natural Resources of Changbai Mountain & Functional Molecules (Yanbian University), Ministry of Education, Yanji 133002, People's Republic of China
*Correspondence e-mail: zqcong@ybu.edu.cn

(Received 8 June 2011; accepted 14 June 2011; online 18 June 2011)

In the title compound, C14H15NO3, all non-H atoms except for those of the methyl and the disordered ethyl groupare approximately co-planar, the largest deviation from the mean plane being 0.0223 (13) Å at the N atom. In the crystal, the packing of mol­ecules through weak inter­molecular C—H⋯O hydrogen-bonding inter­actions leads to the formation of layers parallel to bc plane. Within these layers, there exist slipped π–π stacking inter­actions between symmetry-related fused rings [centroid–centroid distances = 3.527 (3) and 3.554 (3), slippage = 0.988 and 1.011 Å, respectively]. One ethyl group is disordered over two sets of sites with site-occupation factors of 0.54 and 0.46.

Related literature

For background to the title compound, an organic inter­mediate and a fluorescent probe for cyanide and amino acids, see: Kim et al. (2010[Kim, G. J. & Kim, H. J. (2010). Tetrahedron Lett. 51, 2914-2916.]). For electronic and photonic applications of coumarins, see: Murray et al. (1982[Murray, R. D., Mendez, J. & Brown, S. A. (1982). The Natural Coumarins: Occurrence, Chemistry and Biochemistry, p. 227. New York: John Wiley and Sons.]). For the synthesis, see: Wu et al. (2007[Wu, J. S., Liu, W. M., Zhuang, X. Q., Wang, F., Wang, P. F., Tao, S. L., Zhang, X. H., Wu, S. K. & Lee, S. T. (2007). Org. Lett. 9, 33-36.]).

[Scheme 1]

Experimental

Crystal data

  • C14H15NO3

  • Mr = 245.27

  • Monoclinic, C 2/c

  • a = 25.488 (17) Å

  • b = 7.844 (6) Å

  • c = 12.599 (12) Å

  • β = 92.39 (3)°

  • V = 2517 (3) Å3

  • Z = 8

  • Mo Kα radiation

  • μ = 0.09 mm−1

  • T = 295 K

  • 0.41 × 0.39 × 0.21 mm
Data collection

  • Rigaku R-AXIS RAPID diffractometer

  • Absorption correction: multi-scan (ABSCOR; Higashi, 1995[Higashi, T. (1995). ABSCOR. Rigaku Corporation, Tokyo, Japan.]) Tmin = 0.963, Tmax = 0.981

  • 11514 measured reflections

  • 2850 independent reflections

  • 1724 reflections with I > 2σ(I)

  • Rint = 0.033
Refinement

  • R[F2 > 2σ(F2)] = 0.048

  • wR(F2) = 0.144

  • S = 1.06

  • 2850 reflections

  • 184 parameters

  • 1 restraint

  • H-atom parameters constrained

  • Δρmax = 0.14 e Å−3

  • Δρmin = −0.15 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
C8—H8⋯O3i 0.93 2.58 3.367 (4) 143
C9—H9⋯O1ii 0.93 2.55 3.432 (3) 158
C13—H13B⋯O2iii 0.97 2.53 3.388 (3) 147
Symmetry codes: (i) [-x+{\script{1\over 2}}, y+{\script{1\over 2}}, -z+{\script{5\over 2}}]; (ii) [x, -y, z+{\script{1\over 2}}]; (iii) [-x+{\script{1\over 2}}, y+{\script{1\over 2}}, -z+{\script{3\over 2}}].

Data collection: RAPID-AUTO (Rigaku, 1998[Rigaku (1998). RAPID-AUTO. Rigaku Corporation, Tokyo, Japan.]); cell refinement: RAPID-AUTO; data reduction: CrystalStructure (Rigaku, 2002[Rigaku (2002). CrystalStructure. Rigaku/MSC Inc., The Woodlands, Texas, USA.]); 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: ORTEPIII (Burnett & Johnson, 1996[Burnett, M. N. & Johnson, C. K. (1996). ORTEPIII. Report ORNL-6895. Oak Ridge National Laboratory, Tennessee, USA.]) and ORTEP-3 for Windows (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]); software used to prepare material for publication: SHELXL97.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S160053681102294X/dn2698sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S160053681102294X/dn2698Isup2.hkl

Supporting information file. DOI: 10.1107/S160053681102294X/dn2698Isup3.cml

checkCIF report


Comment top

Coumarins are an important class of naturally occurring and synthetic compounds, which have been extentively investigated for electronic and photonic applications (Murray et al., 1982). Herein, we reported the crystal structure of the title compound, an important organic intermediate and a fluorescent probe for cyanide and amino acids (Kim et al., 2010).

The molecule of title compound formed by two fused rings is mainly planar with the exception of the methyl and disordered ethyl group (Fig. 1). The weak intermolcular C—H···O hydrogen bonds (Table 1) link the molecules into layers parallel to the (100) plane. Futhermore, slipped π-π stacking occurs between symetry related fused rings within the layers (Table 2)

Related literature top

For background to the title compound, an organic intermediate and a fluorescent probe for cyanide and amino acids, see: Kim et al. (2010). For electronic and photonic applications of coumarins, see: Murray et al. (1982). For the synthesis, see: Wu et al. (2007).

Experimental top

The title compound was prepared according to the literature (Wu et al., 2007). Single crystals suitable for X-ray diffraction were prepared by recrystallization from mixture of dichloromethane and petroleum (60–90 °C).

Refinement top

Carbon-bound H-atoms were placed in calculated positions (C—H 0.93 to 0.97 Å) and were included in the refinement in the riding model with Uiso(H) = 1.2 or 1.5 Ueq(Cmethyl).

One of the ethyl group is disordered over two positions with a site occupancy in the ratio 0.54/0.46. The refinement of the disordered moieties was carried out using the PART instruction and restraining them to have identical geometry with the SAME instruction available in SHELXL-97 (Sheldrick, 2008)

Computing details top

Data collection: RAPID-AUTO (Rigaku, 1998); cell refinement: RAPID-AUTO (Rigaku, 1998); data reduction: CrystalStructure (Rigaku, 2002); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEPIII (Burnett & Johnson, 1996) and ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The crystal structure of the title compound, with the atom numbering scheme. Displacement ellipsoids of non-H atoms are drawn at the 30% probalility level. H atoms are shown as small spheres of arbitrary radii. Only the major component of the disordered ethyl is represented for clarity.
7-Diethylamino-2-oxo-2H-chromene-3-carbaldehyde top
Crystal data top
C14H15NO3F(000) = 1040
Mr = 245.27Dx = 1.295 Mg m−3
Monoclinic, C2/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2ycCell parameters from 6542 reflections
a = 25.488 (17) Åθ = 3.2–27.5°
b = 7.844 (6) ŵ = 0.09 mm−1
c = 12.599 (12) ÅT = 295 K
β = 92.39 (3)°Block, brown
V = 2517 (3) Å30.41 × 0.39 × 0.21 mm
Z = 8
Data collection top
Rigaku R-AXIS RAPID
diffractometer		2850 independent reflections
Radiation source: fine-focus sealed tube1724 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.033
ω scansθmax = 27.5°, θmin = 3.2°
Absorption correction: multi-scan
(ABSCOR; Higashi, 1995)		h = −32→32
Tmin = 0.963, Tmax = 0.981k = −9→10
11514 measured reflectionsl = −16→16
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.048Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.144H-atom parameters constrained
S = 1.06 w = 1/[σ2(Fo2) + (0.0674P)2 + 0.3544P]
where P = (Fo2 + 2Fc2)/3
2850 reflections(Δ/σ)max < 0.001
184 parametersΔρmax = 0.14 e Å−3
1 restraintΔρmin = −0.15 e Å−3
Crystal data top
C14H15NO3V = 2517 (3) Å3
Mr = 245.27Z = 8
Monoclinic, C2/cMo Kα radiation
a = 25.488 (17) ŵ = 0.09 mm−1
b = 7.844 (6) ÅT = 295 K
c = 12.599 (12) Å0.41 × 0.39 × 0.21 mm
β = 92.39 (3)°
Data collection top
Rigaku R-AXIS RAPID
diffractometer		2850 independent reflections
Absorption correction: multi-scan
(ABSCOR; Higashi, 1995)		1724 reflections with I > 2σ(I)
Tmin = 0.963, Tmax = 0.981Rint = 0.033
11514 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0481 restraint
wR(F2) = 0.144H-atom parameters constrained
S = 1.06Δρmax = 0.14 e Å−3
2850 reflectionsΔρmin = −0.15 e Å−3
184 parameters
Special details top

Experimental. (See detailed section in the paper)

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 > 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)
O10.24299 (4)0.00447 (14)0.88750 (8)0.0556 (3)
O20.17217 (5)−0.12688 (18)0.82505 (10)0.0787 (4)
O30.12022 (6)−0.24463 (18)1.11710 (12)0.0874 (5)
N10.40226 (6)0.2780 (2)0.99586 (12)0.0747 (5)
C10.19772 (6)−0.0872 (2)0.90386 (13)0.0562 (4)
C20.18575 (6)−0.12332 (19)1.01323 (12)0.0533 (4)
C30.21890 (6)−0.0707 (2)1.09396 (12)0.0546 (4)
H30.2105−0.09401.16360.066*
C40.26540 (6)0.01794 (19)1.07523 (11)0.0503 (4)
C50.27674 (6)0.05510 (19)0.96975 (11)0.0478 (4)
C60.32073 (6)0.1413 (2)0.94200 (12)0.0533 (4)
H60.32610.16520.87100.064*
C70.35790 (6)0.1938 (2)1.02108 (13)0.0578 (4)
C80.34695 (7)0.1572 (2)1.12853 (13)0.0636 (5)
H80.37070.19061.18260.076*
C90.30257 (7)0.0747 (2)1.15318 (12)0.0613 (4)
H90.29630.05461.22430.074*
C100.13764 (7)−0.2172 (2)1.03121 (16)0.0679 (5)
H100.1189−0.25920.97190.081*
C11A0.4515 (3)0.2676 (10)1.0761 (7)0.086 (2)0.46
H11A0.44780.17561.12670.103*0.46
H11B0.48360.25091.03870.103*0.46
C12A0.4513 (2)0.4378 (8)1.1303 (5)0.1030 (17)0.46
H12A0.45390.52661.07840.154*0.46
H12B0.48070.44481.18050.154*0.46
H12C0.41930.45101.16690.154*0.46
C11B0.4390 (2)0.3468 (8)1.0753 (5)0.0750 (15)0.54
H11C0.42040.38351.13700.090*0.54
H11D0.45700.44451.04690.090*0.54
C12B0.4784 (2)0.2088 (8)1.1068 (5)0.125 (2)0.54
H12D0.46020.11301.13540.188*0.54
H12E0.50310.25271.15950.188*0.54
H12F0.49660.17341.04550.188*0.54
C130.41299 (8)0.3169 (3)0.88577 (15)0.0742 (5)
H13A0.43740.41160.88470.089*
H13B0.38060.35330.84950.089*
C140.43552 (9)0.1696 (3)0.8251 (2)0.1025 (8)
H14A0.46920.13940.85630.154*
H14B0.43930.20240.75240.154*
H14C0.41230.07350.82800.154*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0602 (6)0.0714 (7)0.0356 (6)−0.0004 (6)0.0062 (4)0.0006 (5)
O20.0830 (8)0.1019 (10)0.0503 (7)−0.0158 (7)−0.0056 (6)0.0026 (7)
O30.0943 (10)0.0941 (10)0.0756 (9)−0.0150 (8)0.0259 (8)0.0101 (7)
N10.0630 (8)0.1053 (12)0.0559 (9)−0.0141 (8)0.0021 (7)0.0042 (8)
C10.0627 (9)0.0599 (10)0.0459 (9)0.0078 (8)0.0030 (7)0.0007 (7)
C20.0613 (9)0.0508 (9)0.0486 (9)0.0078 (8)0.0114 (7)0.0042 (7)
C30.0697 (10)0.0563 (9)0.0387 (8)0.0110 (8)0.0125 (7)0.0036 (7)
C40.0612 (9)0.0544 (9)0.0357 (8)0.0106 (7)0.0091 (6)0.0020 (6)
C50.0565 (8)0.0530 (9)0.0342 (7)0.0129 (7)0.0044 (6)−0.0019 (6)
C60.0602 (9)0.0646 (10)0.0358 (8)0.0082 (8)0.0089 (6)0.0018 (7)
C70.0604 (9)0.0651 (10)0.0479 (9)0.0078 (8)0.0044 (7)0.0016 (7)
C80.0707 (11)0.0787 (12)0.0408 (9)0.0001 (9)−0.0031 (7)0.0005 (8)
C90.0784 (11)0.0727 (11)0.0329 (8)0.0061 (9)0.0046 (7)0.0034 (7)
C100.0754 (11)0.0657 (11)0.0631 (12)0.0018 (9)0.0103 (9)0.0037 (9)
C11A0.069 (4)0.099 (6)0.091 (4)0.013 (4)0.007 (3)0.022 (4)
C12A0.093 (4)0.121 (5)0.094 (4)−0.022 (3)−0.009 (3)−0.008 (4)
C11B0.065 (3)0.086 (4)0.073 (3)−0.015 (3)−0.013 (2)0.005 (3)
C12B0.083 (3)0.152 (5)0.137 (5)0.036 (3)−0.040 (3)0.021 (4)
C130.0713 (11)0.0878 (13)0.0643 (11)−0.0101 (10)0.0123 (9)0.0046 (10)
C140.0940 (15)0.1172 (19)0.0991 (18)0.0080 (14)0.0368 (13)−0.0051 (15)
Geometric parameters (Å, º) top
O1—C51.3774 (19)C9—H90.9300
O1—C11.382 (2)C10—H100.9300
O2—C11.205 (2)C11A—C12A1.500 (8)
O3—C101.206 (2)C11A—H11A0.9700
N1—C71.358 (2)C11A—H11B0.9700
N1—C11B1.446 (6)C12A—H12A0.9600
N1—C131.457 (3)C12A—H12B0.9600
N1—C11A1.581 (8)C12A—H12C0.9600
C1—C21.452 (3)C11B—C12B1.517 (7)
C2—C31.359 (2)C11B—H11C0.9700
C2—C101.456 (3)C11B—H11D0.9700
C3—C41.402 (2)C12B—H12D0.9600
C3—H30.9300C12B—H12E0.9600
C4—C51.402 (2)C12B—H12F0.9600
C4—C91.408 (2)C13—C141.512 (3)
C5—C61.367 (2)C13—H13A0.9700
C6—C71.408 (2)C13—H13B0.9700
C6—H60.9300C14—H14A0.9600
C7—C81.423 (2)C14—H14B0.9600
C8—C91.351 (2)C14—H14C0.9600
C8—H80.9300
C5—O1—C1122.47 (12)O3—C10—C2125.00 (19)
C7—N1—C11B122.7 (3)O3—C10—H10117.5
C7—N1—C13121.03 (15)C2—C10—H10117.5
C11B—N1—C13116.1 (3)C12A—C11A—N1103.2 (5)
C7—N1—C11A118.2 (3)C12A—C11A—H11A111.1
C13—N1—C11A116.3 (3)N1—C11A—H11A111.1
O2—C1—O1115.93 (15)C12A—C11A—H11B111.1
O2—C1—C2127.14 (17)N1—C11A—H11B111.1
O1—C1—C2116.93 (14)H11A—C11A—H11B109.1
C3—C2—C1120.15 (16)N1—C11B—C12B108.5 (5)
C3—C2—C10122.59 (16)N1—C11B—H11C110.0
C1—C2—C10117.26 (16)C12B—C11B—H11C110.0
C2—C3—C4121.88 (14)N1—C11B—H11D110.0
C2—C3—H3119.1C12B—C11B—H11D110.0
C4—C3—H3119.1H11C—C11B—H11D108.4
C3—C4—C5118.13 (14)C11B—C12B—H12D109.5
C3—C4—C9126.03 (14)C11B—C12B—H12E109.5
C5—C4—C9115.84 (15)H12D—C12B—H12E109.5
C6—C5—O1116.32 (13)C11B—C12B—H12F109.5
C6—C5—C4123.28 (14)H12D—C12B—H12F109.5
O1—C5—C4120.40 (15)H12E—C12B—H12F109.5
C5—C6—C7119.92 (15)N1—C13—C14114.33 (19)
C5—C6—H6120.0N1—C13—H13A108.7
C7—C6—H6120.0C14—C13—H13A108.7
N1—C7—C6121.26 (15)N1—C13—H13B108.7
N1—C7—C8121.26 (16)C14—C13—H13B108.7
C6—C7—C8117.48 (16)H13A—C13—H13B107.6
C9—C8—C7120.99 (16)C13—C14—H14A109.5
C9—C8—H8119.5C13—C14—H14B109.5
C7—C8—H8119.5H14A—C14—H14B109.5
C8—C9—C4122.47 (15)C13—C14—H14C109.5
C8—C9—H9118.8H14A—C14—H14C109.5
C4—C9—H9118.8H14B—C14—H14C109.5
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C8—H8···O3i0.932.583.367 (4)143
C9—H9···O1ii0.932.553.432 (3)158
C13—H13B···O2iii0.972.533.388 (3)147
Symmetry codes: (i) −x+1/2, y+1/2, −z+5/2; (ii) x, −y, z+1/2; (iii) −x+1/2, y+1/2, −z+3/2.

Experimental details

Crystal data
Chemical formulaC14H15NO3
Mr245.27
Crystal system, space groupMonoclinic, C2/c
Temperature (K)295
a, b, c (Å)25.488 (17), 7.844 (6), 12.599 (12)
β (°) 92.39 (3)
V (Å3)2517 (3)
Z8
Radiation typeMo Kα
µ (mm−1)0.09
Crystal size (mm)0.41 × 0.39 × 0.21
Data collection
DiffractometerRigaku R-AXIS RAPID
diffractometer
Absorption correctionMulti-scan
(ABSCOR; Higashi, 1995)
Tmin, Tmax0.963, 0.981
No. of measured, independent and
observed [I > 2σ(I)] reflections		11514, 2850, 1724
Rint0.033
(sin θ/λ)max (Å−1)0.649
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.048, 0.144, 1.06
No. of reflections2850
No. of parameters184
No. of restraints1
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å−3)0.14, −0.15

Computer programs: RAPID-AUTO (Rigaku, 1998), CrystalStructure (Rigaku, 2002), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEPIII (Burnett & Johnson, 1996) and ORTEP-3 for Windows (Farrugia, 1997).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C8—H8···O3i0.932.583.367 (4)143.4
C9—H9···O1ii0.932.553.432 (3)157.6
C13—H13B···O2iii0.972.533.388 (3)146.9
Symmetry codes: (i) −x+1/2, y+1/2, −z+5/2; (ii) x, −y, z+1/2; (iii) −x+1/2, y+1/2, −z+3/2.
Table 2 π-π stacking interactions (Å,°) top
Cg1 is the centroid of the O1—C5 ring.

Cg2 is the centroid of the C4—C9 ring
CgICgJCgI···CgJaCgI···P(J)bCgJ···P(I)cSlippage
Cg1Cg1iv3.527 (3)-3.3856 (6)-3.3856 (6)0.988
Cg1Cg2iv3.554 (3)3.4110 (6)3.4044 (6)1.011
Symmetry codes: (iv)1/2-x,-1/2-y,2-z Notes:

a : Distance between centroids

b : Perpendicular distance of CgI on ring plan J

c : Perpendicular distance of CgJ on ring plan I

Slippage = vertical displacement between ring centroids.
 

Acknowledgements

The authors acknowledge financial support from the National Natural Science Foundation of China (grant No. 21062022) and the Open Project of the State Key Laboratory of Supra­molecular Structure and Materials, Jilin University.

References

First citationBurnett, M. N. & Johnson, C. K. (1996). ORTEPIII. Report ORNL-6895. Oak Ridge National Laboratory, Tennessee, USA.  Google Scholar
 First citationFarrugia, L. J. (1997). J. Appl. Cryst. 30, 565.  CrossRef IUCr Journals Google Scholar
 First citationHigashi, T. (1995). ABSCOR. Rigaku Corporation, Tokyo, Japan.  Google Scholar
 First citationKim, G. J. & Kim, H. J. (2010). Tetrahedron Lett. 51, 2914–2916.  CrossRef CAS Google Scholar
 First citationMurray, R. D., Mendez, J. & Brown, S. A. (1982). The Natural Coumarins: Occurrence, Chemistry and Biochemistry, p. 227. New York: John Wiley and Sons.  Google Scholar
 First citationRigaku (1998). RAPID-AUTO. Rigaku Corporation, Tokyo, Japan.  Google Scholar
 First citationRigaku (2002). CrystalStructure. Rigaku/MSC Inc., The Woodlands, Texas, USA.  Google Scholar
 First citationSheldrick, G. M. (2008). Acta Cryst. A64, 112–122.  Web of Science CrossRef CAS IUCr Journals Google Scholar
 First citationWu, J. S., Liu, W. M., Zhuang, X. Q., Wang, F., Wang, P. F., Tao, S. L., Zhang, X. H., Wu, S. K. & Lee, S. T. (2007). Org. Lett. 9, 33–36.  Web of Science CrossRef PubMed CAS Google Scholar

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Journal logoCRYSTALLOGRAPHIC
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ISSN: 2056-9890
Volume 67| Part 7| July 2011| Page o1713
doi:10.1107/S160053681102294X
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