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The structure of quinoline N-oxide dihydrate, C9H7NO·2H2O, has been determined from X-ray powder diffraction data, using grid search technique and a bond-restrained Rietveld refinement. The structure features an interesting system of co-operative hydrogen bonds, which apparently involves all four `active' H atoms, and is based on the infinite chains formed by two alternating symmetry-independent water molecules. The chains are further interlinked through two more symmetry-independent hydrogen bonds which make use of the N-oxide O atom as hydrogen-bond acceptor.
Supporting information
CCDC reference: 193774
Key indicators
- Powder X-ray study
- T = 293 K
- Mean (C-C) = 0.009 Å
- H-atom completeness 64%
- R factor = 0.000
- wR factor = 0.000
- Data-to-parameter ratio = 0.0
checkCIF results
No syntax errors found
ADDSYM reports no extra symmetry
Alert Level C:
PLAT_202 Alert C Isotropic non-H Atoms in Anion/Solvent = 2
General Notes
FORMU_01 There is a discrepancy between the atom counts in the
_chemical_formula_sum and the formula from the _atom_site* data.
Atom count from _chemical_formula_sum:C9 H11 N1 O3
Atom count from the _atom_site data: C9 H7 N1 O3
CELLZ_01
From the CIF: _cell_formula_units_Z 4
From the CIF: _chemical_formula_sum C9 H11 N O3
TEST: Compare cell contents of formula and atom_site data
atom Z*formula cif sites diff
C 36.00 36.00 0.00
H 44.00 28.00 16.00
N 4.00 4.00 0.00
O 12.00 12.00 0.00
Difference between formula and atom_site contents detected.
WARNING: H atoms missing from atom site list. Is this intentional?
CHEMW_03
From the CIF: _cell_formula_units_Z 4
From the CIF: _chemical_formula_weight 181.19
TEST: Calculate formula weight from _atom_site_*
atom mass num sum
O 16.00 3.00 48.00
N 14.01 1.00 14.01
C 12.01 9.00 108.10
H 1.01 7.00 7.06
Calculated formula weight 177.16
The ratio of given/expected molecular weight as calculated
from the _atom_site* data lies outside
the range 0.99 <> 1.01
0 Alert Level A = Potentially serious problem
0 Alert Level B = Potential problem
1 Alert Level C = Please check
Data collection: local program; data reduction: local program; program(s) used to solve structure: MRIA (Zlokazov & Chernyshev, 1992); program(s) used to refine structure: MRIA; molecular graphics: PCMODEL (Version 7.0) [Reference?]; software used to prepare material for publication: MRIA and PARST (Nardelli, 1983).
Crystal data top
C9H7NO·2H2O | F(000) = 384 |
Mr = 181.19 | Dx = 1.285 Mg m−3 |
Monoclinic, P21/n | Melting point: 51(1) K |
a = 9.484 (3) Å | Cu Kα radiation, λ = 1.5418 Å |
b = 16.235 (5) Å | T = 293 K |
c = 6.907 (2) Å | Particle morphology: no specific habit |
β = 118.25 (2)° | light grey |
V = 936.8 (5) Å3 | flat_sheet, 12 × 12 mm |
Z = 4 | |
Data collection top
X-ray powder diffractometer DRON-4.07 | Data collection mode: reflection |
Radiation source: BSV-28, line-focus sealed tube | Scan method: step |
Pyrolitic graphite crystal monochromator | 2θmin = 10°, 2θmax = 60°, 2θstep = 0.02° |
Specimen mounting: The powder was sprinkled on the sample holder. | |
Refinement top
Refinement on Inet | 126 parameters |
Least-squares matrix: full with fixed elements per cycle | 1 constraint |
Rp = 0.028 | H atoms treated by a mixture of independent and constrained refinement |
Rwp = 0.040 | Weighting scheme based on measured s.u.'s |
Rexp = 0.012 | (Δ/σ)max = 0.02 |
2501 data points | Background function: Chebyshev polynomial up to the 5th order' |
Profile function: split-type pseudo-Voigt (Toraya, 1986) | Preferred orientation correction: Spherical harmonics expansion (Ahtee et al., 1989) up to the 6th order. |
Special details top
Experimental. specimen was rotated in its plane |
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. |
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top | x | y | z | Uiso*/Ueq | |
C1 | −0.0298 (9) | −0.0533 (3) | 0.2292 (13) | 0.143 (4)* | |
C2 | −0.2676 (5) | 0.0249 (3) | 0.0699 (6) | 0.056 (3)* | |
C3 | −0.0121 (8) | 0.0980 (3) | 0.2405 (11) | 0.100 (3)* | |
C4 | 0.2258 (6) | 0.0126 (3) | 0.3986 (9) | 0.080 (4)* | |
C5 | 0.2409 (11) | 0.1629 (5) | 0.4134 (15) | 0.160 (4)* | |
O6 | 0.0141 (6) | 0.2410 (3) | 0.2452 (9) | 0.119 (2)* | |
C7 | −0.1906 (6) | −0.0485 (3) | 0.1189 (9) | 0.102 (3)* | |
C8 | −0.1796 (8) | 0.0981 (3) | 0.1177 (11) | 0.158 (4)* | |
C9 | 0.0664 (6) | 0.0207 (3) | 0.2929 (9) | 0.099 (4)* | |
C10 | 0.3182 (7) | 0.0853 (4) | 0.4675 (11) | 0.150 (3)* | |
N11 | 0.0828 (6) | 0.1714 (3) | 0.3009 (9) | 0.144 (3)* | |
H1 | 0.0200 | −0.1040 | 0.2702 | 0.051* | |
H2 | −0.3797 | 0.0279 | −0.0154 | 0.051* | |
H4 | 0.2761 | −0.0379 | 0.4423 | 0.051* | |
H5 | 0.3049 | 0.2106 | 0.4562 | 0.051* | |
H7 | −0.2514 | −0.0986 | 0.0830 | 0.051* | |
H8 | −0.2343 | 0.1475 | 0.0809 | 0.051* | |
H10 | 0.4296 | 0.0816 | 0.5447 | 0.051* | |
OW1 | −0.0545 (3) | 0.2796 (2) | 0.5565 (4) | 0.039 (2)* | |
OW2 | 0.1435 (5) | 0.2862 (2) | −0.0136 (7) | 0.118 (2)* | |
Geometric parameters (Å, º) top
O6—N11 | 1.269 (7) | C3—C8 | 1.403 (9) |
N11—C3 | 1.431 (7) | C4—C9 | 1.338 (7) |
N11—C5 | 1.33 (1) | C4—C10 | 1.412 (8) |
O6—OW1 | 2.601 (7) | C5—C10 | 1.42 (1) |
O6—OW2 | 2.705 (8) | C1—H1 | 0.92 |
OW1—OW2i | 2.660 (9) | C2—H2 | 0.94 |
OW1—OW2ii | 2.875 (9) | C8—H8 | 0.92 |
C1—C7 | 1.346 (9) | C4—H4 | 0.92 |
C1—C9 | 1.445 (8) | C10—H10 | 0.93 |
C2—C7 | 1.354 (7) | C5—H5 | 0.94 |
C2—C8 | 1.399 (7) | C7—H7 | 0.94 |
| | | |
C3—N11—O6 | 119.4 (5) | C7—C1—H1 | 120 |
C5—N11—O6 | 123.0 (7) | C7—C2—H2 | 121 |
C3—N11—C5 | 117.6 (7) | C8—C2—H2 | 118 |
N11—C5—C10 | 123.1 (8) | C9—C4—H4 | 123 |
C5—C10—C4 | 119.6 (6) | C10—C4—H4 | 119 |
C10—C4—C9 | 117.6 (6) | N11—C5—H5 | 119 |
C4—C9—C3 | 123.2 (6) | C10—C5—H5 | 118 |
C9—C1—C7 | 120.5 (6) | C1—C7—H7 | 119 |
C1—C7—C2 | 121.7 (5) | C2—C7—H7 | 120 |
C7—C2—C8 | 119.8 (5) | C2—C8—H8 | 119 |
C2—C8—C3 | 121.3 (6) | C3—C8—H8 | 120 |
C8—C3—C9 | 117.6 (6) | C4—C10—H10 | 120 |
C3—C9—C1 | 118.6 (4) | C5—C10—H10 | 121 |
C9—C1—H1 | 119 | | |
Symmetry codes: (i) x, y, z+1; (ii) x−1/2, −y+1/2, z+1/2. |
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