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ISSN: 2056-9890

2,2′-({4-[(4-Nitro­phen­yl)diazen­yl]phen­yl}imino)­di­ethanol

aDepartment of Chemistry, Faculty of Science, Kasetsart University, Bangkok 10903, Thailand, and bDepartment of Textile Science, Faculty of Agro-Industry, Kasetsart University, Bangkok 10900, Thailand
*Correspondence e-mail: fsciska@ku.ac.th

(Received 21 November 2012; accepted 30 November 2012; online 5 December 2012)

In the title compound, C16H18N4O4, the mol­ecule assumes an E conformation with respect to the N=N double bond. The aromatic rings are not coplanar, with a dihedral angle of 7.51 (8)°. The nitro group is tilted by 4.71 (11)° relative to the attached benzene ring. In the crystal, mol­ecules are connected through O—H⋯O hydrogen bonds forming a double-stranded chain parallel to the b axis.

Related literature

For the properties of azo disperse dyes, see: Suesat et al. (2011[Suesat, J., Mungmeechai, T., Suwanruji, P., Parasuk, W., Taylor, J. A. & Phillips, D. A. S. (2011). Color Technol. 127, 217-222.]). For the structure of related compounds, see: Zhang et al. (1998[Zhang, D.-C., Ge, L.-Q., Fei, Z.-H., Zhang, Y.-Q. & Yu, K.-B. (1998). Acta Cryst. C54, 1909-1911.]); Adams et al. (2004[Adams, H., Allen, R. W. K., Chin, J., O'Sullivan, B., Styring, P. & Sutton, L. R. (2004). Acta Cryst. E60, o289-o290.]).

[Scheme 1]

Experimental

Crystal data
  • C16H18N4O4

  • Mr = 330.34

  • Monoclinic, P 21 /c

  • a = 19.000 (3) Å

  • b = 7.3502 (16) Å

  • c = 11.0825 (16) Å

  • β = 92.060 (8)°

  • V = 1546.7 (5) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.10 mm−1

  • T = 296 K

  • 0.24 × 0.16 × 0.04 mm

Data collection
  • Bruker APEXII CCD diffractometer

  • 7008 measured reflections

  • 2671 independent reflections

  • 1642 reflections with I > 2σ(I)

  • Rint = 0.032

Refinement
  • R[F2 > 2σ(F2)] = 0.044

  • wR(F2) = 0.152

  • S = 0.93

  • 2671 reflections

  • 219 parameters

  • H-atom parameters constrained

  • Δρmax = 0.17 e Å−3

  • Δρmin = −0.19 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O1—H1⋯O4i 0.82 1.90 2.700 (3) 164
O4—H4⋯O1ii 0.82 1.90 2.718 (3) 172
Symmetry codes: (i) x, y+1, z; (ii) [-x, y-{\script{1\over 2}}, -z+{\script{1\over 2}}].

Data collection: APEX2 (Bruker, 2011[Bruker (2011). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2011[Bruker (2011). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; 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: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXTL.

Supporting information


Comment top

A series of azo disperse dyes was recently synthesized by our group in order to study the influence of substituents on the chromatic properties of the dyes (Suesat et al., 2011). We report herein the crystal structure of one of these dyes.

The molecule of the title compound (Fig. 1) displays an E configuration about the NN double bond and is not planar, the dihedral angle between the aromatic ring being 7.51 (8)°. This value may be compared with those observed in the related compounds 4'-(dimethylamino)-2-nitroazobenzene (5.3 (2)°; Zhang et al., 1998) and 4'-(dimethylamino)-4-nitroazobenzene (2.1 (4)°; Adams et al., 2004). The nitro group is tilted by 4.71 (11)° with respect to the attached C7–C11 benzene ring. In the crystal structure, molecules are linked by O—H···O hydrogen bonds (Table 1) to form double-stranded chain parallel to the b axis (Fig. 2).

Related literature top

For the properties of azo disperse dyes, see: Suesat et al. (2011). For the structure of related compounds, see: Zhang et al. (1998); Adams et al. (2004).

Experimental top

The azo disperse dye was prepared by dissolving 4-nitroaniline (0.01 mol) in 50 ml of an acetic acid/propionic acid (43:7 v/v) mixture. The solution was stirred and the temperature was kept in the range of 0–5°C. Diazotization took place when nitrosyl sulfuric acid (HNO5S) was added to the solution and stirred at 0–5°C for 30–60 minutes. The coupling component N-bis-β-hydroxyethyl aniline (0.01 mol) was then dissolved in 40 ml acetone, distilled water was added to make the total volume of 200 ml and sulfamic acid (0.5 g) was added. The coupling reaction was performed by slow addition of the diazonium salt solution to the coupling solution at 0–5°C. The reaction continued for 2 h with stirring and was monitored using TLC. On completion of the coupling reaction, the dye precipitate was collected by filtration and dried at room temperature. The dye was purified by recrystallization in n-propanol. Single crystals suitable for X-ray analysis were obtained by slow evaporation of a purified dye solution in n-propanol.

Refinement top

All H atoms of the compound were placed in the calculated positions with C—H = 0.93 and 0.97 Å, O—H = 0.82 Å and included in the cycles of refinement in a rigid model, with Uiso(H) = 1.2 Ueq(C) and 1.5 Ueq(O).

Structure description top

A series of azo disperse dyes was recently synthesized by our group in order to study the influence of substituents on the chromatic properties of the dyes (Suesat et al., 2011). We report herein the crystal structure of one of these dyes.

The molecule of the title compound (Fig. 1) displays an E configuration about the NN double bond and is not planar, the dihedral angle between the aromatic ring being 7.51 (8)°. This value may be compared with those observed in the related compounds 4'-(dimethylamino)-2-nitroazobenzene (5.3 (2)°; Zhang et al., 1998) and 4'-(dimethylamino)-4-nitroazobenzene (2.1 (4)°; Adams et al., 2004). The nitro group is tilted by 4.71 (11)° with respect to the attached C7–C11 benzene ring. In the crystal structure, molecules are linked by O—H···O hydrogen bonds (Table 1) to form double-stranded chain parallel to the b axis (Fig. 2).

For the properties of azo disperse dyes, see: Suesat et al. (2011). For the structure of related compounds, see: Zhang et al. (1998); Adams et al. (2004).

Computing details top

Data collection: APEX2 (Bruker, 2011); cell refinement: SAINT (Bruker, 2011); data reduction: SAINT (Bruker, 2011); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (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 50% probability level.
[Figure 2] Fig. 2. The chain structure of the title compound. Hydrogen bonds are shown as dotted lines.
2,2'-({4-[(4-Nitrophenyl)diazenyl]phenyl}imino)diethanol top
Crystal data top
C16H18N4O4F(000) = 696
Mr = 330.34Dx = 1.419 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 1201 reflections
a = 19.000 (3) Åθ = 3.0–21.9°
b = 7.3502 (16) ŵ = 0.10 mm1
c = 11.0825 (16) ÅT = 296 K
β = 92.060 (8)°Plate, purple
V = 1546.7 (5) Å30.24 × 0.16 × 0.04 mm
Z = 4
Data collection top
Bruker APEXII CCD
diffractometer
1642 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.032
Graphite monochromatorθmax = 25.1°, θmin = 1.1°
φ and ω scansh = 2222
7008 measured reflectionsk = 87
2671 independent reflectionsl = 1312
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)] = 0.044Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.152H-atom parameters constrained
S = 0.93 w = 1/[σ2(Fo2) + (0.096P)2]
where P = (Fo2 + 2Fc2)/3
2671 reflections(Δ/σ)max < 0.001
219 parametersΔρmax = 0.17 e Å3
0 restraintsΔρmin = 0.19 e Å3
Crystal data top
C16H18N4O4V = 1546.7 (5) Å3
Mr = 330.34Z = 4
Monoclinic, P21/cMo Kα radiation
a = 19.000 (3) ŵ = 0.10 mm1
b = 7.3502 (16) ÅT = 296 K
c = 11.0825 (16) Å0.24 × 0.16 × 0.04 mm
β = 92.060 (8)°
Data collection top
Bruker APEXII CCD
diffractometer
1642 reflections with I > 2σ(I)
7008 measured reflectionsRint = 0.032
2671 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0440 restraints
wR(F2) = 0.152H-atom parameters constrained
S = 0.93Δρmax = 0.17 e Å3
2671 reflectionsΔρmin = 0.19 e Å3
219 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
O10.05195 (11)0.8516 (3)0.17672 (18)0.0594 (6)
H10.06440.95650.19050.089*
O20.76929 (9)0.9038 (3)0.02037 (17)0.0597 (6)
O30.74369 (9)0.9967 (3)0.20053 (17)0.0586 (6)
O40.06568 (10)0.2095 (3)0.22729 (19)0.0633 (6)
H40.02850.25250.24960.095*
N10.14613 (9)0.5386 (3)0.14546 (17)0.0354 (5)
N20.42757 (9)0.6797 (3)0.04905 (17)0.0365 (5)
N30.44265 (10)0.7473 (3)0.05171 (17)0.0368 (5)
N40.72717 (11)0.9329 (3)0.1042 (2)0.0411 (6)
C10.07605 (14)0.7966 (4)0.0624 (2)0.0497 (8)
H1A0.11930.86040.04530.060*
H1B0.04100.82670.00030.060*
C20.08899 (12)0.5953 (4)0.0634 (2)0.0408 (7)
H2A0.04620.53400.08580.049*
H2B0.09950.55660.01760.049*
C30.21506 (12)0.5627 (3)0.1166 (2)0.0317 (6)
C40.27042 (12)0.5308 (3)0.2010 (2)0.0367 (6)
H4A0.26060.48250.27610.044*
C50.33886 (12)0.5695 (4)0.1749 (2)0.0379 (6)
H50.37430.54980.23350.046*
C60.35640 (11)0.6375 (3)0.06305 (19)0.0320 (6)
C70.51515 (12)0.7925 (3)0.0583 (2)0.0332 (6)
C80.56560 (12)0.7559 (4)0.0318 (2)0.0406 (7)
H80.55250.69920.10260.049*
C90.63476 (13)0.8029 (4)0.0174 (2)0.0403 (7)
H90.66870.77760.07760.048*
C100.65295 (11)0.8877 (3)0.0873 (2)0.0328 (6)
C110.53504 (12)0.8809 (4)0.1621 (2)0.0398 (7)
H110.50130.90800.22230.048*
C120.60435 (13)0.9292 (4)0.1773 (2)0.0399 (7)
H120.61770.98850.24700.048*
C130.12743 (13)0.4915 (4)0.2676 (2)0.0400 (6)
H13A0.08220.54620.28340.048*
H13B0.16200.54460.32360.048*
C140.12301 (14)0.2927 (4)0.2926 (3)0.0536 (8)
H14A0.16660.23470.27080.064*
H14B0.11740.27410.37840.064*
C150.23411 (12)0.6236 (4)0.0017 (2)0.0371 (6)
H150.19910.63980.05820.045*
C160.30250 (12)0.6596 (3)0.0241 (2)0.0353 (6)
H160.31320.69940.10100.042*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0536 (12)0.0370 (13)0.0894 (15)0.0012 (10)0.0307 (11)0.0022 (10)
O20.0321 (11)0.0772 (16)0.0690 (13)0.0058 (10)0.0091 (10)0.0015 (11)
O30.0404 (11)0.0767 (16)0.0600 (13)0.0067 (10)0.0176 (9)0.0071 (11)
O40.0494 (13)0.0405 (13)0.1017 (16)0.0089 (10)0.0257 (12)0.0144 (11)
N10.0246 (10)0.0402 (14)0.0417 (11)0.0018 (9)0.0043 (9)0.0004 (9)
N20.0280 (12)0.0409 (14)0.0410 (12)0.0022 (10)0.0065 (9)0.0014 (10)
N30.0286 (12)0.0438 (14)0.0380 (12)0.0035 (10)0.0042 (9)0.0029 (10)
N40.0296 (12)0.0413 (14)0.0527 (13)0.0019 (10)0.0063 (11)0.0080 (11)
C10.0353 (15)0.056 (2)0.0587 (17)0.0061 (14)0.0085 (13)0.0114 (14)
C20.0262 (13)0.0494 (18)0.0468 (15)0.0054 (12)0.0009 (11)0.0059 (13)
C30.0281 (13)0.0275 (14)0.0398 (13)0.0012 (11)0.0041 (10)0.0048 (11)
C40.0329 (14)0.0404 (17)0.0370 (13)0.0025 (12)0.0052 (11)0.0026 (11)
C50.0284 (13)0.0441 (17)0.0410 (14)0.0009 (12)0.0019 (10)0.0024 (12)
C60.0276 (13)0.0323 (15)0.0367 (13)0.0011 (11)0.0066 (10)0.0044 (11)
C70.0263 (13)0.0388 (16)0.0346 (13)0.0017 (11)0.0048 (10)0.0064 (11)
C80.0349 (15)0.0511 (19)0.0360 (13)0.0032 (13)0.0040 (11)0.0072 (12)
C90.0316 (14)0.0484 (18)0.0406 (14)0.0008 (12)0.0034 (11)0.0018 (12)
C100.0252 (12)0.0348 (15)0.0386 (14)0.0001 (11)0.0053 (10)0.0076 (11)
C110.0306 (14)0.0571 (19)0.0318 (13)0.0000 (13)0.0004 (10)0.0003 (12)
C120.0379 (14)0.0500 (18)0.0323 (13)0.0045 (13)0.0074 (11)0.0006 (12)
C130.0287 (13)0.0439 (17)0.0479 (15)0.0041 (12)0.0095 (11)0.0005 (12)
C140.0384 (16)0.0450 (19)0.0784 (19)0.0011 (14)0.0154 (14)0.0106 (15)
C150.0303 (13)0.0440 (17)0.0368 (13)0.0008 (12)0.0006 (10)0.0012 (11)
C160.0332 (14)0.0400 (16)0.0331 (12)0.0016 (12)0.0058 (11)0.0006 (11)
Geometric parameters (Å, º) top
O1—C11.421 (3)C5—C61.389 (3)
O1—H10.8200C5—H50.9300
O2—N41.224 (3)C6—C161.392 (3)
O3—N41.217 (2)C7—C111.386 (3)
O4—C141.424 (3)C7—C81.386 (3)
O4—H40.8200C8—C91.373 (3)
N1—C31.371 (3)C8—H80.9300
N1—C21.452 (3)C9—C101.373 (3)
N1—C131.454 (3)C9—H90.9300
N2—N31.265 (3)C10—C121.369 (3)
N2—C61.401 (3)C11—C121.380 (3)
N3—C71.422 (3)C11—H110.9300
N4—C101.467 (3)C12—H120.9300
C1—C21.500 (4)C13—C141.490 (4)
C1—H1A0.9700C13—H13A0.9700
C1—H1B0.9700C13—H13B0.9700
C2—H2A0.9700C14—H14A0.9700
C2—H2B0.9700C14—H14B0.9700
C3—C41.403 (3)C15—C161.367 (3)
C3—C151.409 (3)C15—H150.9300
C4—C51.372 (3)C16—H160.9300
C4—H4A0.9300
C1—O1—H1109.5C11—C7—N3116.5 (2)
C14—O4—H4109.5C8—C7—N3124.3 (2)
C3—N1—C2121.05 (19)C9—C8—C7120.5 (2)
C3—N1—C13121.1 (2)C9—C8—H8119.8
C2—N1—C13116.69 (18)C7—C8—H8119.8
N3—N2—C6115.78 (19)C10—C9—C8118.9 (2)
N2—N3—C7112.83 (19)C10—C9—H9120.5
O3—N4—O2123.5 (2)C8—C9—H9120.5
O3—N4—C10118.6 (2)C12—C10—C9122.2 (2)
O2—N4—C10118.0 (2)C12—C10—N4118.9 (2)
O1—C1—C2109.4 (2)C9—C10—N4118.9 (2)
O1—C1—H1A109.8C12—C11—C7120.8 (2)
C2—C1—H1A109.8C12—C11—H11119.6
O1—C1—H1B109.8C7—C11—H11119.6
C2—C1—H1B109.8C10—C12—C11118.4 (2)
H1A—C1—H1B108.2C10—C12—H12120.8
N1—C2—C1114.0 (2)C11—C12—H12120.8
N1—C2—H2A108.8N1—C13—C14115.1 (2)
C1—C2—H2A108.8N1—C13—H13A108.5
N1—C2—H2B108.8C14—C13—H13A108.5
C1—C2—H2B108.8N1—C13—H13B108.5
H2A—C2—H2B107.7C14—C13—H13B108.5
N1—C3—C4121.5 (2)H13A—C13—H13B107.5
N1—C3—C15122.1 (2)O4—C14—C13111.9 (2)
C4—C3—C15116.4 (2)O4—C14—H14A109.2
C5—C4—C3121.2 (2)C13—C14—H14A109.2
C5—C4—H4A119.4O4—C14—H14B109.2
C3—C4—H4A119.4C13—C14—H14B109.2
C4—C5—C6121.5 (2)H14A—C14—H14B107.9
C4—C5—H5119.2C16—C15—C3121.9 (2)
C6—C5—H5119.2C16—C15—H15119.1
C5—C6—C16117.9 (2)C3—C15—H15119.1
C5—C6—N2116.2 (2)C15—C16—C6120.9 (2)
C16—C6—N2125.9 (2)C15—C16—H16119.6
C11—C7—C8119.2 (2)C6—C16—H16119.6
C6—N2—N3—C7178.01 (19)C8—C9—C10—C120.8 (4)
C3—N1—C2—C176.6 (3)C8—C9—C10—N4178.2 (2)
C13—N1—C2—C191.0 (3)O3—N4—C10—C124.0 (3)
O1—C1—C2—N165.8 (3)O2—N4—C10—C12176.2 (2)
C2—N1—C3—C4171.5 (2)O3—N4—C10—C9175.0 (2)
C13—N1—C3—C44.5 (3)O2—N4—C10—C94.8 (3)
C2—N1—C3—C157.4 (3)C8—C7—C11—C121.3 (4)
C13—N1—C3—C15174.4 (2)N3—C7—C11—C12179.5 (2)
N1—C3—C4—C5174.5 (2)C9—C10—C12—C111.1 (4)
C15—C3—C4—C54.4 (3)N4—C10—C12—C11178.0 (2)
C3—C4—C5—C61.6 (4)C7—C11—C12—C100.0 (4)
C4—C5—C6—C162.2 (4)C3—N1—C13—C1490.9 (3)
C4—C5—C6—N2177.1 (2)C2—N1—C13—C14101.5 (3)
N3—N2—C6—C5177.7 (2)N1—C13—C14—O467.5 (3)
N3—N2—C6—C161.5 (4)N1—C3—C15—C16175.4 (2)
N2—N3—C7—C11174.9 (2)C4—C3—C15—C163.6 (4)
N2—N3—C7—C84.2 (3)C3—C15—C16—C60.1 (4)
C11—C7—C8—C91.5 (4)C5—C6—C16—C153.0 (4)
N3—C7—C8—C9179.4 (2)N2—C6—C16—C15176.2 (2)
C7—C8—C9—C100.5 (4)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1···O4i0.821.902.700 (3)164
O4—H4···O1ii0.821.902.718 (3)172
Symmetry codes: (i) x, y+1, z; (ii) x, y1/2, z+1/2.

Experimental details

Crystal data
Chemical formulaC16H18N4O4
Mr330.34
Crystal system, space groupMonoclinic, P21/c
Temperature (K)296
a, b, c (Å)19.000 (3), 7.3502 (16), 11.0825 (16)
β (°) 92.060 (8)
V3)1546.7 (5)
Z4
Radiation typeMo Kα
µ (mm1)0.10
Crystal size (mm)0.24 × 0.16 × 0.04
Data collection
DiffractometerBruker APEXII CCD
Absorption correction
No. of measured, independent and
observed [I > 2σ(I)] reflections
7008, 2671, 1642
Rint0.032
(sin θ/λ)max1)0.597
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.044, 0.152, 0.93
No. of reflections2671
No. of parameters219
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.17, 0.19

Computer programs: APEX2 (Bruker, 2011), SAINT (Bruker, 2011), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1···O4i0.8201.9042.700 (3)163.8
O4—H4···O1ii0.8201.9042.718 (3)172.0
Symmetry codes: (i) x, y+1, z; (ii) x, y1/2, z+1/2.
 

Acknowledgements

The authors thank the Kasetsart University Research and Development Institute and the Department of Chemistry, Faculty of Science, Kasetsart University, for research funds.

References

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