1,4-Bis(4-nitro­phen­oxy)benzene

The title compound, C₁₈H₁₂N₂O₆, crystallizes with two half-mol­ecules in the asymmetric unit. All mol­ecules lie on a centre of inversion. The dihedral angles between the central and terminal benzene rings are 74.75 (4) and 85.25 (5)° for the two mol­ecules in the asymmetric unit.

Key indicators

• Single-crystal X-ray study
• T = 173 K
• Mean [sigma](C-C) = 0.002 Å
• R factor = 0.041
• wR factor = 0.107
• Data-to-parameter ratio = 15.4

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT241_ALERT_2_C Check High      Ueq as Compared to Neighbors for        O1A
PLAT250_ALERT_2_C Large U3/U1 Ratio for Average U(i,j) Tensor ....       2.02

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   2 ALERT level C = Check and explain
   0 ALERT level G = General alerts; check

   0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   2 ALERT type 2 Indicator that the structure model may be wrong or deficient
   0 ALERT type 3 Indicator that the structure quality may be low
   0 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

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Computing details

Data collection: X-AREA (Stoe & Cie, 2001); cell refinement: X-AREA; data reduction: X-AREA; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: XP in SHELXTL-Plus (Sheldrick, 1991); software used to prepare material for publication: SHELXL97.

1,4-bis(4-nitrophenoxy)benzene

Crystal data

C18H12N2O6	Z = 2
Mr = 352.30	F(000) = 364
Triclinic, P1	Dx = 1.472 Mg m^−3
Hall symbol: -P 1	Melting point: 238 K
a = 7.2861 (6) Å	Mo Kα radiation, λ = 0.71073 Å
b = 10.1381 (9) Å	Cell parameters from 17691 reflections
c = 12.0838 (11) Å	θ = 3.6–27.6°
α = 91.973 (7)°	µ = 0.11 mm^−1
β = 106.497 (7)°	T = 173 K
γ = 110.152 (6)°	Needle, colourless
V = 794.74 (12) Å^3	0.38 × 0.11 × 0.10 mm

Data collection

Stoe IPDS-II two-circle diffractometer	3064 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.040
Graphite monochromator	θmax = 27.6°, θmin = 3.6°
ω scans	h = −9→9
18200 measured reflections	k = −12→13
3644 independent reflections	l = −15→15

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F^2 > 2σ(F^2)] = 0.042	H-atom parameters constrained
wR(F^2) = 0.107	w = 1/[σ^2(Fo^2) + (0.0545P)^2 + 0.2087P] where P = (Fo^2 + 2Fc^2)/3
S = 1.03	(Δ/σ)max < 0.001
3644 reflections	Δρmax = 0.26 e Å^−3
236 parameters	Δρmin = −0.19 e Å^−3
0 restraints	Extinction correction: SHELXL97, Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.021 (4)

Special details

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 (Ų)

	x	y	z	Uiso*/Ueq
O1	0.14779 (15)	0.80747 (10)	0.11671 (8)	0.0338 (2)
N1	0.78574 (17)	0.94769 (13)	0.54132 (9)	0.0296 (2)
C1	0.30488 (18)	0.85081 (13)	0.22210 (10)	0.0243 (2)
C2	0.4658 (2)	0.98324 (14)	0.24912 (12)	0.0313 (3)
H2	0.4673	1.0505	0.1963	0.038*
C3	0.6243 (2)	1.01528 (14)	0.35473 (12)	0.0296 (3)
H3	0.7346	1.1050	0.3751	0.035*
C4	0.61885 (18)	0.91429 (13)	0.42987 (10)	0.0240 (2)
C5	0.45993 (19)	0.78210 (14)	0.40322 (11)	0.0255 (3)
H5	0.4602	0.7144	0.4557	0.031*
C6	0.30028 (19)	0.75037 (13)	0.29843 (11)	0.0255 (3)
H6	0.1891	0.6611	0.2790	0.031*
O11	0.79566 (18)	0.85029 (13)	0.59845 (9)	0.0435 (3)
O12	0.90903 (15)	1.07143 (11)	0.57310 (9)	0.0381 (3)
C11	0.08101 (18)	0.90985 (13)	0.06053 (11)	0.0257 (3)
C12	0.0635 (2)	0.90984 (14)	−0.05716 (11)	0.0281 (3)
H12	0.1071	0.8483	−0.0953	0.034*
C13	−0.0186 (2)	1.00122 (14)	−0.11846 (11)	0.0287 (3)
H13	−0.0317	1.0027	−0.1989	0.034*
O1A	0.59391 (16)	0.43120 (14)	0.36471 (11)	0.0536 (4)
N1A	0.3508 (2)	0.67143 (16)	−0.03318 (11)	0.0406 (3)
C1A	0.5467 (2)	0.49469 (15)	0.26699 (12)	0.0309 (3)
C2A	0.68091 (19)	0.62226 (14)	0.24903 (12)	0.0292 (3)
H2A	0.8146	0.6686	0.3036	0.035*
C3A	0.6151 (2)	0.68010 (14)	0.14967 (12)	0.0300 (3)
H3A	0.7031	0.7672	0.1355	0.036*
C4A	0.4190 (2)	0.60919 (15)	0.07120 (11)	0.0291 (3)
C5A	0.2849 (2)	0.48138 (15)	0.08789 (12)	0.0324 (3)
H5A	0.1521	0.4345	0.0326	0.039*
C6A	0.3504 (2)	0.42418 (15)	0.18759 (13)	0.0353 (3)
H6A	0.2618	0.3373	0.2017	0.042*
O11A	0.4690 (2)	0.78570 (17)	−0.04620 (13)	0.0668 (4)
O12A	0.1781 (2)	0.60780 (15)	−0.10325 (9)	0.0521 (3)
C11A	0.8013 (2)	0.46948 (15)	0.43081 (12)	0.0334 (3)
C12A	0.8704 (2)	0.55025 (15)	0.53978 (13)	0.0357 (3)
H12A	0.7814	0.5842	0.5661	0.043*
C13A	1.0724 (2)	0.58088 (15)	0.61013 (12)	0.0366 (3)
H13A	1.1229	0.6356	0.6853	0.044*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0392 (5)	0.0223 (5)	0.0282 (5)	0.0114 (4)	−0.0067 (4)	0.0025 (4)
N1	0.0289 (5)	0.0376 (6)	0.0234 (5)	0.0161 (5)	0.0057 (4)	0.0007 (4)
C1	0.0258 (6)	0.0238 (6)	0.0217 (5)	0.0113 (5)	0.0026 (4)	0.0027 (4)
C2	0.0330 (7)	0.0248 (6)	0.0309 (7)	0.0081 (5)	0.0048 (5)	0.0115 (5)
C3	0.0265 (6)	0.0238 (6)	0.0328 (7)	0.0060 (5)	0.0049 (5)	0.0064 (5)
C4	0.0235 (5)	0.0290 (6)	0.0208 (5)	0.0126 (5)	0.0055 (4)	0.0026 (5)
C5	0.0286 (6)	0.0274 (6)	0.0240 (6)	0.0124 (5)	0.0104 (5)	0.0095 (5)
C6	0.0252 (6)	0.0228 (6)	0.0276 (6)	0.0079 (5)	0.0082 (5)	0.0056 (5)
O11	0.0501 (6)	0.0494 (7)	0.0281 (5)	0.0235 (5)	0.0012 (4)	0.0112 (5)
O12	0.0320 (5)	0.0401 (6)	0.0338 (5)	0.0111 (4)	0.0020 (4)	−0.0067 (4)
C11	0.0234 (6)	0.0192 (5)	0.0260 (6)	0.0057 (4)	−0.0023 (4)	0.0031 (4)
C12	0.0291 (6)	0.0253 (6)	0.0260 (6)	0.0105 (5)	0.0027 (5)	−0.0001 (5)
C13	0.0317 (6)	0.0280 (6)	0.0203 (5)	0.0090 (5)	0.0019 (5)	0.0033 (5)
O1A	0.0282 (5)	0.0634 (8)	0.0492 (7)	−0.0003 (5)	0.0003 (5)	0.0384 (6)
N1A	0.0513 (8)	0.0603 (9)	0.0310 (6)	0.0394 (7)	0.0192 (6)	0.0206 (6)
C1A	0.0271 (6)	0.0326 (7)	0.0294 (6)	0.0082 (5)	0.0060 (5)	0.0124 (5)
C2A	0.0232 (6)	0.0301 (7)	0.0315 (6)	0.0069 (5)	0.0076 (5)	0.0079 (5)
C3A	0.0300 (6)	0.0297 (7)	0.0372 (7)	0.0138 (5)	0.0164 (5)	0.0133 (5)
C4A	0.0361 (7)	0.0367 (7)	0.0253 (6)	0.0236 (6)	0.0124 (5)	0.0106 (5)
C5A	0.0295 (6)	0.0328 (7)	0.0298 (6)	0.0127 (5)	0.0008 (5)	0.0004 (5)
C6A	0.0292 (7)	0.0278 (7)	0.0393 (7)	0.0044 (5)	0.0038 (6)	0.0083 (6)
O11A	0.0640 (8)	0.0842 (10)	0.0731 (9)	0.0393 (8)	0.0324 (7)	0.0589 (8)
O12A	0.0641 (8)	0.0756 (9)	0.0265 (5)	0.0453 (7)	0.0049 (5)	0.0086 (5)
C11A	0.0284 (6)	0.0327 (7)	0.0304 (6)	0.0043 (5)	0.0037 (5)	0.0174 (5)
C12A	0.0416 (8)	0.0324 (7)	0.0384 (7)	0.0152 (6)	0.0174 (6)	0.0149 (6)
C13A	0.0456 (8)	0.0295 (7)	0.0246 (6)	0.0040 (6)	0.0080 (6)	0.0049 (5)

Geometric parameters (Å, º)

O1—C1	1.3828 (15)	O1A—C1A	1.3790 (16)
O1—C11	1.4085 (15)	O1A—C11A	1.4003 (17)
N1—O12	1.2339 (16)	N1A—O11A	1.229 (2)
N1—O11	1.2347 (16)	N1A—O12A	1.2306 (19)
N1—C4	1.4704 (16)	N1A—C4A	1.4665 (17)
C1—C6	1.3955 (17)	C1A—C2A	1.3945 (18)
C1—C2	1.3971 (18)	C1A—C6A	1.3950 (19)
C2—C3	1.3940 (18)	C2A—C3A	1.3894 (18)
C2—H2	0.9500	C2A—H2A	0.9500
C3—C4	1.3895 (18)	C3A—C4A	1.391 (2)
C3—H3	0.9500	C3A—H3A	0.9500
C4—C5	1.3891 (18)	C4A—C5A	1.390 (2)
C5—C6	1.3919 (18)	C5A—C6A	1.388 (2)
C5—H5	0.9500	C5A—H5A	0.9500
C6—H6	0.9500	C6A—H6A	0.9500
C11—C13^i	1.3891 (19)	C11A—C13A^ii	1.385 (2)
C11—C12	1.3914 (18)	C11A—C12A	1.387 (2)
C12—C13	1.3936 (18)	C12A—C13A	1.394 (2)
C12—H12	0.9500	C12A—H12A	0.9500
C13—C11^i	1.3891 (19)	C13A—C11A^ii	1.385 (2)
C13—H13	0.9500	C13A—H13A	0.9500
C1—O1—C11	118.85 (9)	C1A—O1A—C11A	118.44 (10)
O12—N1—O11	123.24 (11)	O11A—N1A—O12A	122.96 (13)
O12—N1—C4	118.48 (11)	O11A—N1A—C4A	118.25 (14)
O11—N1—C4	118.28 (11)	O12A—N1A—C4A	118.79 (14)
O1—C1—C6	115.75 (11)	O1A—C1A—C2A	123.19 (12)
O1—C1—C2	122.82 (11)	O1A—C1A—C6A	115.11 (12)
C6—C1—C2	121.33 (11)	C2A—C1A—C6A	121.67 (12)
C3—C2—C1	119.09 (12)	C3A—C2A—C1A	118.60 (12)
C3—C2—H2	120.5	C3A—C2A—H2A	120.7
C1—C2—H2	120.5	C1A—C2A—H2A	120.7
C4—C3—C2	119.15 (12)	C2A—C3A—C4A	119.29 (12)
C4—C3—H3	120.4	C2A—C3A—H3A	120.4
C2—C3—H3	120.4	C4A—C3A—H3A	120.4
C5—C4—C3	122.05 (11)	C5A—C4A—C3A	122.48 (12)
C5—C4—N1	118.64 (11)	C5A—C4A—N1A	118.68 (13)
C3—C4—N1	119.31 (11)	C3A—C4A—N1A	118.84 (13)
C4—C5—C6	118.94 (11)	C6A—C5A—C4A	118.17 (12)
C4—C5—H5	120.5	C6A—C5A—H5A	120.9
C6—C5—H5	120.5	C4A—C5A—H5A	120.9
C5—C6—C1	119.44 (11)	C5A—C6A—C1A	119.78 (13)
C5—C6—H6	120.3	C5A—C6A—H6A	120.1
C1—C6—H6	120.3	C1A—C6A—H6A	120.1
C13^i—C11—C12	121.59 (12)	C13A^ii—C11A—C12A	121.87 (13)
C13^i—C11—O1	120.77 (12)	C13A^ii—C11A—O1A	119.82 (14)
C12—C11—O1	117.42 (11)	C12A—C11A—O1A	118.18 (14)
C11—C12—C13	119.24 (12)	C11A—C12A—C13A	118.94 (14)
C11—C12—H12	120.4	C11A—C12A—H12A	120.5
C13—C12—H12	120.4	C13A—C12A—H12A	120.5
C11^i—C13—C12	119.17 (12)	C11A^ii—C13A—C12A	119.19 (13)
C11^i—C13—H13	120.4	C11A^ii—C13A—H13A	120.4
C12—C13—H13	120.4	C12A—C13A—H13A	120.4
C11—O1—C1—C6	150.47 (12)	C11A—O1A—C1A—C2A	−20.0 (2)
C11—O1—C1—C2	−33.18 (18)	C11A—O1A—C1A—C6A	161.88 (14)
O1—C1—C2—C3	−176.35 (12)	O1A—C1A—C2A—C3A	−177.50 (14)
C6—C1—C2—C3	−0.2 (2)	C6A—C1A—C2A—C3A	0.5 (2)
C1—C2—C3—C4	0.5 (2)	C1A—C2A—C3A—C4A	−0.3 (2)
C2—C3—C4—C5	−0.1 (2)	C2A—C3A—C4A—C5A	−0.2 (2)
C2—C3—C4—N1	179.99 (12)	C2A—C3A—C4A—N1A	179.80 (12)
O12—N1—C4—C5	−169.00 (11)	O11A—N1A—C4A—C5A	178.73 (14)
O11—N1—C4—C5	11.10 (17)	O12A—N1A—C4A—C5A	−0.79 (19)
O12—N1—C4—C3	10.89 (17)	O11A—N1A—C4A—C3A	−1.3 (2)
O11—N1—C4—C3	−169.01 (12)	O12A—N1A—C4A—C3A	179.19 (12)
C3—C4—C5—C6	−0.58 (19)	C3A—C4A—C5A—C6A	0.6 (2)
N1—C4—C5—C6	179.30 (11)	N1A—C4A—C5A—C6A	−179.38 (13)
C4—C5—C6—C1	0.89 (18)	C4A—C5A—C6A—C1A	−0.5 (2)
O1—C1—C6—C5	175.89 (11)	O1A—C1A—C6A—C5A	178.07 (14)
C2—C1—C6—C5	−0.52 (19)	C2A—C1A—C6A—C5A	−0.1 (2)
C1—O1—C11—C13^i	−54.41 (17)	C1A—O1A—C11A—C13A^ii	−75.01 (19)
C1—O1—C11—C12	130.95 (12)	C1A—O1A—C11A—C12A	109.05 (16)
C13^i—C11—C12—C13	0.0 (2)	C13A^ii—C11A—C12A—C13A	−0.3 (2)
O1—C11—C12—C13	174.59 (11)	O1A—C11A—C12A—C13A	175.54 (12)
C11—C12—C13—C11^i	0.0 (2)	C11A—C12A—C13A—C11A^ii	0.3 (2)

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