PMCCPMCCPMCC

Search tips
Search criteria 

Advanced

 
Logo of actaeInternational Union of Crystallographysearchopen accessarticle submissionjournal home pagethis article
 
Acta Crystallogr Sect E Struct Rep Online. 2010 June 1; 66(Pt 6): o1476–o1477.
Published online 2010 May 29. doi:  10.1107/S1600536810018994
PMCID: PMC2979536

N-Methacryloyl-4-(piperidin-1-yl)-1,8-naphthalimide

Abstract

In the title compound, C21H20N2O3, the naphthalimide unit is almost planar (r.m.s. deviation for the 15 non-H atoms = 0.059 Å). The carboximide N atom and the five C atoms of the 2-methyl­prop-2-enoyl substituent also lie in a plane (r.m.s. deviation = 0.009 Å), which subtends an angle of 84.34 (7)° to the naphthalamide plane. This orients the =CH2 group of the vinyl fragment towards the naphthalimide rings, giving the mol­ecule an extended configuration. The piperidine ring adopts a chair conformation and there is evidence for some delocalization between the naphthalene and piperidine units, the C—Npip bond length being 1.404 (4) Å. In the crystal structure, π–π contacts with centroid–centroid distances of 3.5351 (18) and 3.7794 (18) Å supported by C—H(...)O hydrogen bonds link adjacent mol­ecules in a head-to-tail fashion, forming dimers. These are further stabilized by other C—H(...)O contacts of varying strength, which stack the mol­ecules down the b axis.

Related literature

For background to the applications of 1,8-naphthalamides, see: McAdam et al. (2003 [triangle], 2010 [triangle]); Flood et al. (2007 [triangle]). For their incorporation into polymer systems, see: Dana et al. (2007 [triangle]); Munro et al. (2008 [triangle]). For related structures, see: McAdam et al. (2003 [triangle]); Easton et al. (1992 [triangle]); Batchelor et al. (1997 [triangle]); Tagg et al. (2008 [triangle]). For comparative bond-length data, see: Allen et al. (1987 [triangle]) and for ring conformations, see: Cremer & Pople (1975 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-66-o1476-scheme1.jpg

Experimental

Crystal data

  • C21H20N2O3
  • M r = 348.39
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-66-o1476-efi1.jpg
  • a = 29.049 (3) Å
  • b = 6.9852 (7) Å
  • c = 17.1503 (17) Å
  • β = 102.013 (6)°
  • V = 3403.7 (6) Å3
  • Z = 8
  • Mo Kα radiation
  • μ = 0.09 mm−1
  • T = 90 K
  • 0.65 × 0.11 × 0.04 mm

Data collection

  • Bruker APEXII CCD diffractometer
  • Absorption correction: multi-scan (SADABS; Bruker, 2006 [triangle]) T min = 0.838, T max = 1.000
  • 12211 measured reflections
  • 1843 independent reflections
  • 1440 reflections with I > 2σ(I)
  • R int = 0.075
  • θmax = 21.2°

Refinement

  • R[F 2 > 2σ(F 2)] = 0.054
  • wR(F 2) = 0.152
  • S = 1.12
  • 1843 reflections
  • 236 parameters
  • H-atom parameters constrained
  • Δρmax = 0.20 e Å−3
  • Δρmin = −0.21 e Å−3

Data collection: APEX2 (Bruker, 2006 [triangle]); cell refinement: APEX2 and SAINT (Bruker, 2006 [triangle]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]) and TITAN2000 (Hunter & Simpson, 1999 [triangle]); molecular graphics: SHELXTL (Sheldrick, 2008 [triangle]) and Mercury (Macrae et al., 2008 [triangle]); software used to prepare material for publication: SHELXL97, enCIFer (Allen et al., 2004 [triangle]), PLATON (Spek, 2009 [triangle]) and publCIF (Westrip, 2010 [triangle]).

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536810018994/hb5457sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810018994/hb5457Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Acknowledgments

We thank the New Economy Research Fund; grant No. UOO-X0808 for support of this work and the University of Otago for purchase of the diffractometer.

supplementary crystallographic information

Comment

We have recently been interested in naphthalimide derivatives as components of donor-acceptor arrays because, as good acceptors, they often exhibit strong fluorescence together with redox triggered LMCT transitions in the near-IR (McAdam et al. 2003, 2010; Flood et al. 2007). We have also incorporated fluorescent naphthalimides into polymer systems (Dana et al., 2007; Munro et al., 2008). Methacrylate derivatives are polymer precursors and the title compound, I, Fig 1, was synthesised to further scope the possibilities of incorporating fluorescent naphthalimide derivatives into polymers.

The title compound comprises a 1,8-naphthalimide ring system with a piperidino ring at the C4 position of the naphthalene ring and a 2-methyl-prop-2-en-1-one substituent on the N1 atom of the dicarboxamide ring. The naphthalimide unit is planar with an rms deviation from the best fit meanplane through all 15 non-hydrogen atoms of 0.0494 Å. The C13 atom of the propenone headgroup and the N2 atom of the piperidine ring are both displaced slightly from this plane with deviations 0.170 (4) and 0.004 (3) Å respectively both in the same direction. Bond lengths within the dicarboxamide ring are normal (Allen et al., 1987) and consistent with a degree of delocalisation in the naphthalimide system. In keeping with previous observations (Easton et al., 1992; Batchelor et al., 1997; Tagg et al., 2008) the N1—C13 bond is relatively long, 1.486 (4) Å, suggesting that there is a node at the N1 atom. In contrast the C4—N2 bond is short, 1.404 (4) Å, indicating a degree of delocalisation between the naphthalene and piperidine units. The piperidine ring adopts a classical chair conformation with Cremer-Pople puckering parameters [Q(2) = 0.005 (4) Å, [var phi](2) = 154 (5)° and Q(3) = -0.575 (43) Å (Cremer & Pople, 1975). The N1, C13, (O1), C14, C15, C16 segment of the propenone is also planar (rms deviation 0.0920 Å) and subtends an angle of 84.44 (7)° to the naphthalimide plane. This orients the =C15H2 of the vinyl fragment towards the naphthalimide rings.

In the crystal structure intermolecular π–π contacts occur between the unsubstituted C5···C8, C9, C10 naphthalene ring of one molecule and the C1, C8, C9, C11, C12, N1 carboxamide and substituted C1···C4, C9, C10 rings of an adjacent molecule to form head to tail dimers, with centroid to centroid distances of 3.5351 (18) and 3.7794 (18) Å respectively, Fig 2. These contacts are supported by weak C25–H25B···O11 hydrogen bonds. The dimers are further aggregated by a range of additional C—H···O contacts, Table 2, to give an extensive three dimensional network structure with molecules stacked down the b axis, Fig. 3.

Experimental

4-Piperidine-1,8-naphthalic amide (200 mg, 0.72 mmol) was dissolved in distilled dichloromethane (DCM) (30 ml) under N2, triethylamine (3 ml) and methylacryoyl chloride (0.18 ml, 1.4 mmol) were added sequentially by syringe at 273 K. The mixture was stirred overnight. The mixture was then washed with distilled water (3 times) and the organic phase dried over MgSO4. The solvent was evaporated under reduced pressure and the crude product purified by silica gel column chromatography with hexane-ethyl acetate (50:50, v/v) to give an orange solid (168.3 mg, 0.48 mmol); yield of 67.2%. The compound was recrystallised by the slow diffusion of hexane into a concentrated solution of I in DCM to give very thin orange blades/needles of (I).

Refinement

All H-atoms were refined using a riding model with d(C—H) = 0.95 Å, Uiso=1.2Ueq (C) for aromatic, 0.99 Å, Uiso=1.2Ueq (C) for CH2 and 0.98 Å, Uiso = 1.5Ueq (C) for CH3 H atoms. Crystals were very thin and weakly diffracting and measurable reflection data could not be observed beyond θ = 21.2 °. This results in both low data resolution and a poor data/parameter ratio.

Figures

Fig. 1.
The structure of (I) showing displacement ellipsoids drawn at the 50% probability level.
Fig. 2.
Head to tail dimers of (I) formed by π–π contacts (black dotted lines) augmented by C—-H···O hydrogen bonds (blue dashed lines). The blue sphere represents the centroid of the the C5···C8,C9,C10 ...
Fig. 3.
The crystal packing of (I) viewed down the b axis with hydrogen bonds drawn as blue dashed lines.

Crystal data

C21H20N2O3F(000) = 1472
Mr = 348.39Dx = 1.360 Mg m3
Monoclinic, C2/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2ycCell parameters from 2032 reflections
a = 29.049 (3) Åθ = 2.4–21.1°
b = 6.9852 (7) ŵ = 0.09 mm1
c = 17.1503 (17) ÅT = 90 K
β = 102.013 (6)°Blade, orange
V = 3403.7 (6) Å30.65 × 0.11 × 0.04 mm
Z = 8

Data collection

Bruker APEXII CCD diffractometer1843 independent reflections
Radiation source: fine-focus sealed tube1440 reflections with I > 2σ(I)
graphiteRint = 0.075
ω scansθmax = 21.2°, θmin = 2.4°
Absorption correction: multi-scan (SADABS; Bruker, 2006)h = −29→29
Tmin = 0.838, Tmax = 1.000k = −7→6
12211 measured reflectionsl = −17→17

Refinement

Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.054Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.152H-atom parameters constrained
S = 1.12w = 1/[σ2(Fo2) + (0.0822P)2] where P = (Fo2 + 2Fc2)/3
1843 reflections(Δ/σ)max < 0.001
236 parametersΔρmax = 0.20 e Å3
0 restraintsΔρmin = −0.21 e Å3

Special details

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)

xyzUiso*/Ueq
C10.70398 (11)0.5991 (4)0.6119 (2)0.0221 (9)
C20.72082 (12)0.6631 (5)0.6879 (2)0.0237 (9)
H20.69910.70170.71930.028*
C30.76855 (12)0.6733 (5)0.7204 (2)0.0242 (9)
H30.77880.72120.77300.029*
C40.80161 (12)0.6150 (4)0.6777 (2)0.0217 (9)
C50.81694 (12)0.5175 (4)0.5443 (2)0.0227 (9)
H50.84990.52700.56400.027*
C60.80025 (12)0.4695 (4)0.4661 (2)0.0255 (9)
H60.82190.44500.43260.031*
C70.75190 (12)0.4560 (4)0.4347 (2)0.0225 (9)
H70.74080.42070.38050.027*
C80.72057 (12)0.4939 (4)0.4825 (2)0.0217 (9)
C90.73615 (12)0.5448 (4)0.5643 (2)0.0201 (9)
C100.78588 (12)0.5534 (4)0.5964 (2)0.0218 (9)
C110.66975 (13)0.4926 (4)0.4468 (2)0.0236 (9)
C120.65327 (13)0.5993 (5)0.5773 (2)0.0236 (9)
C130.58901 (13)0.5604 (5)0.4598 (2)0.0303 (10)
C140.56012 (12)0.3865 (5)0.4482 (2)0.0294 (10)
C150.57626 (13)0.2257 (5)0.4834 (2)0.0351 (10)
H15A0.60680.22170.51660.042*
H15B0.55740.11350.47570.042*
C160.51218 (13)0.4093 (6)0.3979 (3)0.0469 (12)
H16A0.49530.28710.39510.070*
H16B0.51470.44890.34410.070*
H16C0.49490.50680.42130.070*
C210.87594 (12)0.4410 (5)0.7217 (2)0.0300 (10)
H21A0.86470.35620.67540.036*
H21B0.86940.37700.76970.036*
C220.92823 (12)0.4714 (5)0.7318 (2)0.0346 (10)
H22A0.93520.52480.68210.041*
H22B0.94470.34710.74240.041*
C230.94596 (13)0.6084 (5)0.8008 (2)0.0380 (11)
H23A0.94240.54910.85160.046*
H23B0.97980.63600.80430.046*
C240.91787 (12)0.7929 (5)0.7872 (2)0.0350 (10)
H24A0.92810.87900.83340.042*
H24B0.92420.85800.73920.042*
C250.86568 (12)0.7558 (5)0.7762 (2)0.0300 (9)
H25A0.85880.69910.82540.036*
H25B0.84830.87810.76580.036*
N10.63959 (9)0.5398 (4)0.49807 (17)0.0237 (8)
N20.85019 (10)0.6250 (4)0.70929 (16)0.0262 (8)
O10.57432 (8)0.7182 (4)0.43997 (15)0.0387 (7)
O110.65310 (8)0.4540 (3)0.37740 (14)0.0293 (7)
O120.62306 (9)0.6481 (3)0.61341 (15)0.0331 (7)

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
C10.020 (2)0.018 (2)0.026 (2)−0.0025 (15)−0.0009 (18)−0.0004 (16)
C20.028 (2)0.021 (2)0.024 (2)0.0006 (16)0.0074 (19)0.0028 (16)
C30.024 (2)0.024 (2)0.024 (2)−0.0007 (16)0.0020 (18)0.0024 (16)
C40.021 (2)0.0138 (19)0.029 (2)−0.0024 (15)0.0029 (19)0.0030 (15)
C50.021 (2)0.0160 (19)0.031 (2)0.0053 (15)0.0041 (18)0.0035 (16)
C60.029 (2)0.022 (2)0.027 (2)0.0027 (16)0.0106 (19)0.0023 (16)
C70.027 (2)0.0163 (19)0.022 (2)0.0003 (15)0.0016 (18)−0.0002 (15)
C80.028 (2)0.0070 (19)0.029 (2)0.0007 (15)0.0031 (19)0.0015 (15)
C90.021 (2)0.0130 (19)0.026 (2)−0.0017 (15)0.0034 (18)0.0024 (16)
C100.028 (2)0.0116 (18)0.024 (2)−0.0012 (15)0.0005 (18)0.0025 (15)
C110.029 (2)0.016 (2)0.025 (2)0.0004 (16)0.003 (2)0.0036 (16)
C120.026 (2)0.020 (2)0.025 (2)−0.0007 (17)0.008 (2)0.0005 (17)
C130.029 (2)0.028 (3)0.031 (2)0.0066 (19)0.0008 (19)0.0009 (18)
C140.027 (2)0.031 (3)0.028 (2)−0.0014 (19)0.0020 (18)−0.0012 (18)
C150.029 (2)0.032 (3)0.042 (3)−0.0043 (19)0.002 (2)−0.003 (2)
C160.030 (2)0.050 (3)0.053 (3)0.002 (2)−0.011 (2)−0.001 (2)
C210.027 (2)0.024 (2)0.036 (2)0.0026 (16)−0.0004 (19)0.0035 (17)
C220.030 (2)0.037 (2)0.035 (2)0.0060 (18)0.0037 (19)0.0006 (18)
C230.024 (2)0.050 (3)0.038 (3)0.0006 (19)0.0013 (19)−0.008 (2)
C240.028 (2)0.042 (3)0.033 (2)−0.0062 (18)0.0034 (19)−0.0139 (18)
C250.026 (2)0.034 (2)0.028 (2)−0.0011 (17)0.0019 (18)−0.0093 (18)
N10.0192 (18)0.0226 (17)0.0269 (19)−0.0013 (13)−0.0011 (15)−0.0011 (13)
N20.0242 (19)0.0272 (18)0.0248 (18)0.0010 (14)−0.0007 (14)−0.0044 (14)
O10.0375 (17)0.0292 (17)0.0462 (18)0.0089 (13)0.0015 (14)0.0043 (13)
O110.0325 (17)0.0280 (15)0.0238 (16)−0.0017 (11)−0.0024 (13)−0.0014 (11)
O120.0269 (16)0.0365 (16)0.0349 (17)−0.0011 (12)0.0043 (14)−0.0032 (12)

Geometric parameters (Å, °)

C1—C21.368 (5)C13—N11.486 (4)
C1—C91.415 (5)C14—C151.315 (5)
C1—C121.469 (5)C14—C161.486 (5)
C2—C31.384 (5)C15—H15A0.9500
C2—H20.9500C15—H15B0.9500
C3—C41.385 (5)C16—H16A0.9800
C3—H30.9500C16—H16B0.9800
C4—N21.404 (4)C16—H16C0.9800
C4—C101.440 (5)C21—N21.480 (4)
C5—C61.370 (4)C21—C221.508 (5)
C5—C101.418 (5)C21—H21A0.9900
C5—H50.9500C21—H21B0.9900
C6—C71.399 (5)C22—C231.525 (5)
C6—H60.9500C22—H22A0.9900
C7—C81.372 (5)C22—H22B0.9900
C7—H70.9500C23—C241.517 (5)
C8—C91.426 (5)C23—H23A0.9900
C8—C111.476 (5)C23—H23B0.9900
C9—C101.436 (5)C24—C251.511 (5)
C11—O111.218 (4)C24—H24A0.9900
C11—N11.403 (4)C24—H24B0.9900
C12—O121.223 (4)C25—N21.462 (4)
C12—N11.397 (4)C25—H25A0.9900
C13—O11.205 (4)C25—H25B0.9900
C13—C141.466 (5)
C2—C1—C9119.3 (3)H15A—C15—H15B120.0
C2—C1—C12121.0 (3)C14—C16—H16A109.5
C9—C1—C12119.6 (3)C14—C16—H16B109.5
C1—C2—C3122.0 (3)H16A—C16—H16B109.5
C1—C2—H2119.0C14—C16—H16C109.5
C3—C2—H2119.0H16A—C16—H16C109.5
C2—C3—C4121.2 (3)H16B—C16—H16C109.5
C2—C3—H3119.4N2—C21—C22111.2 (3)
C4—C3—H3119.4N2—C21—H21A109.4
C3—C4—N2122.2 (3)C22—C21—H21A109.4
C3—C4—C10119.0 (3)N2—C21—H21B109.4
N2—C4—C10118.7 (3)C22—C21—H21B109.4
C6—C5—C10121.2 (3)H21A—C21—H21B108.0
C6—C5—H5119.4C21—C22—C23110.3 (3)
C10—C5—H5119.4C21—C22—H22A109.6
C5—C6—C7121.0 (3)C23—C22—H22A109.6
C5—C6—H6119.5C21—C22—H22B109.6
C7—C6—H6119.5C23—C22—H22B109.6
C8—C7—C6119.7 (3)H22A—C22—H22B108.1
C8—C7—H7120.2C24—C23—C22109.3 (3)
C6—C7—H7120.2C24—C23—H23A109.8
C7—C8—C9121.4 (3)C22—C23—H23A109.8
C7—C8—C11118.8 (3)C24—C23—H23B109.8
C9—C8—C11119.6 (3)C22—C23—H23B109.8
C1—C9—C8121.5 (3)H23A—C23—H23B108.3
C1—C9—C10120.0 (3)C25—C24—C23111.5 (3)
C8—C9—C10118.4 (3)C25—C24—H24A109.3
C5—C10—C9118.2 (3)C23—C24—H24A109.3
C5—C10—C4123.2 (3)C25—C24—H24B109.3
C9—C10—C4118.4 (3)C23—C24—H24B109.3
O11—C11—N1119.4 (3)H24A—C24—H24B108.0
O11—C11—C8124.5 (3)N2—C25—C24110.0 (3)
N1—C11—C8116.1 (3)N2—C25—H25A109.7
O12—C12—N1119.1 (3)C24—C25—H25A109.7
O12—C12—C1124.1 (3)N2—C25—H25B109.7
N1—C12—C1116.8 (3)C24—C25—H25B109.7
O1—C13—C14124.1 (3)H25A—C25—H25B108.2
O1—C13—N1118.2 (3)C12—N1—C11126.2 (3)
C14—C13—N1117.7 (3)C12—N1—C13117.1 (3)
C15—C14—C13120.4 (3)C11—N1—C13115.8 (3)
C15—C14—C16124.0 (3)C4—N2—C25117.0 (3)
C13—C14—C16115.5 (3)C4—N2—C21116.7 (2)
C14—C15—H15A120.0C25—N2—C21111.5 (3)
C14—C15—H15B120.0

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
C21—H21B···O12i0.992.543.485 (4)160
C24—H24A···O12ii0.992.673.365 (4)127
C21—H21A···O11iii0.992.363.258 (4)150
C25—H25B···O11iv0.992.723.278 (4)117

Symmetry codes: (i) −x+3/2, y−1/2, −z+3/2; (ii) −x+3/2, y+1/2, −z+3/2; (iii) −x+3/2, −y+1/2, −z+1; (iv) −x+3/2, −y+3/2, −z+1.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: HB5457).

References

  • Allen, F. H., Johnson, O., Shields, G. P., Smith, B. R. & Towler, M. (2004). J. Appl. Cryst.37, 335–338.
  • Allen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1–19.
  • Batchelor, R. A., Hunter, C. A. & Simpson, J. (1997). Acta Cryst. C53, 1117–1119.
  • Bruker (2006). APEX2, SAINT and SADABS Bruker AXS Inc., Madison, Wisconsin, USA.
  • Cremer, D. & Pople, J. A. (1975). J. Am. Chem. Soc.97, 1354–1358.
  • Dana, B. H., McAdam, C. J., Robinson, B. H., Simpson, J. & Wang, H. (2007). J. Inorg. Organomet. Polym. Mater.17, 547–559.
  • Easton, C. J., Gulbis, J. M., Hoskins, B. F., Scharfbillig, I. M. & Tiekink, E. R. T. (1992). Z. Kristallogr.199, 249–254.
  • Flood, A. H., McAdam, C. J., Gordon, K. C., Kjaergaard, H. G., Manning, A. R., Robinson, B. H. & Simpson, J. (2007). Polyhedron, 26, 448–455.
  • Hunter, K. A. & Simpson, J. (1999). TITAN2000 University of Otago, New Zealand.
  • 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.
  • McAdam, C. J., Morgan, J. L., Robinson, B. H., Simpson, J., Rieger, P. H. & Rieger, A. L. (2003). Organometallics, 22, 5126– 5136.
  • McAdam, C. J., Robinson, B. H., Simpson, J. & Tagg, T. (2010). Organometallics, doi: 10.1021/om1000452.
  • Munro, N. H., Hanton, L. R., Robinson, B. H. & Simpson, J. (2008). React. Funct. Polym.68 671–678 .
  • Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. [PubMed]
  • Spek, A. L. (2009). Acta Cryst. D65, 148–155. [PMC free article] [PubMed]
  • Tagg, T., McAdam, C. J., Robinson, B. H. & Simpson, J. (2008). Acta Cryst. C64, o388–o391. [PubMed]
  • Westrip, S. P. (2010). J. Appl. Cryst.43 Submitted.

Articles from Acta Crystallographica Section E: Structure Reports Online are provided here courtesy of International Union of Crystallography