Cocrystal assembled by 1,4-diiodotetrafluorobenzene and phenothiazine based on C—I...π/N/S halogen bond and other assisting interactions

The halogen-bonded cocrystal of 1,4-diiodotetrafluorobenzene (1,4-DITFB) with the butterfly-shape non-planar heterocyclic compound phenothiazine (PHT) was successfully assembled by the conventional solution-based method. X-ray single-crystal diffraction analysis reveals a 3:2 stoichiometric ratio for the cocrystal (1,4-DITFB/PHT), and the cocrystal structure is constructed via C—I...π, C—I...N and C—I...S halogen bonds as well as other assisting interactions (e.g. C—H...F/S hydrogen bond, C—H...H—C and C—F...F—C bonds). The small shift of the 1,4-DITFB vibrational band to lower frequencies in FT–IR and Raman spectroscopies provide evidence to confirm the existence of the halogen bond. In addition, the non-planarity of the PHT molecule in the cocrystal results in PHT emitting weak phosphorescence and relatively strong delayed fluorescence. Thus, a wide range of delayed fluorescence and weak phosphorescence could play a significant role in selecting a proper π-conjugated system to engineer functional cocrystal and luminescent materials by halogen bonds.

Computing details

Data collection: Bruker APEX2; cell refinement: Bruker SAINT; data reduction: Bruker SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: Bruker SHELXTL; software used to prepare material for publication: Bruker SHELXTL.

(I)

Crystal data

C21H9F6I3NS	Z = 2
Mr = 802.05	F(000) = 742
Triclinic, P1	Dx = 2.399 Mg m^−3
a = 5.9807 (5) Å	Mo Kα radiation, λ = 0.71073 Å
b = 14.139 (1) Å	Cell parameters from 4498 reflections
c = 14.2774 (10) Å	θ = 2.5–27.5°
α = 68.516 (1)°	µ = 4.38 mm^−1
β = 81.348 (3)°	T = 110 K
γ = 86.090 (3)°	Block, yellow
V = 1110.53 (14) Å^3	0.23 × 0.21 × 0.20 mm

Data collection

Bruker APEX-II CCD diffractometer	3766 independent reflections
Radiation source: fine-focus sealed tube	3406 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.015
φ and ω scans	θmax = 25.0°, θmin = 2.6°
Absorption correction: multi-scan SADABS	h = −5→7
Tmin = 0.433, Tmax = 0.475	k = −16→16
5147 measured reflections	l = −16→13

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.032	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.073	H atoms treated by a mixture of independent and constrained refinement
S = 1.09	w = 1/[σ^2(Fo^2) + (0.0168P)^2 + 5.9805P] where P = (Fo^2 + 2Fc^2)/3
3766 reflections	(Δ/σ)max = 0.001
289 parameters	Δρmax = 1.84 e Å^−3
0 restraints	Δρmin = −2.86 e Å^−3

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 > 2sigma(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
F1	0.8510 (5)	−0.1314 (2)	0.6993 (3)	0.0391 (8)
F2	0.6436 (7)	0.0056 (3)	0.5557 (3)	0.0548 (11)
F3	1.1394 (6)	0.2572 (2)	0.5395 (3)	0.0523 (11)
F4	1.3504 (6)	0.1197 (3)	0.6829 (4)	0.0642 (13)
F5	−0.1476 (6)	0.8062 (2)	0.0752 (3)	0.0415 (9)
F6	0.3559 (7)	1.0518 (3)	0.0666 (3)	0.0547 (11)
I1	1.27240 (7)	−0.11907 (3)	0.80569 (3)	0.03396 (12)
I2	0.72059 (8)	0.24068 (3)	0.43002 (3)	0.04041 (13)
I3	0.26853 (6)	0.81263 (3)	0.18510 (3)	0.03000 (11)
N1	0.3581 (7)	0.3821 (3)	0.2783 (3)	0.0218 (9)
H1	0.2293	0.3657	0.2930	0.026*
S1	0.8204 (2)	0.47153 (10)	0.19124 (10)	0.0218 (3)
C1	1.1068 (8)	−0.0101 (4)	0.6956 (4)	0.0209 (11)
C2	0.9253 (8)	−0.0358 (4)	0.6611 (4)	0.0203 (10)
C3	0.8179 (9)	0.0359 (4)	0.5865 (4)	0.0242 (11)
C4	0.8879 (8)	0.1355 (4)	0.5431 (4)	0.0195 (10)
C5	1.0674 (8)	0.1607 (4)	0.5777 (4)	0.0254 (12)
C6	1.1753 (9)	0.0902 (4)	0.6523 (5)	0.0293 (13)
C7	0.6530 (8)	0.4155 (3)	0.1335 (4)	0.0180 (10)
C8	0.7395 (9)	0.4069 (4)	0.0406 (4)	0.0233 (11)
H8	0.8829	0.4344	0.0070	0.028*
C9	0.6156 (10)	0.3583 (4)	−0.0023 (4)	0.0299 (13)
H9	0.6764	0.3506	−0.0645	0.036*
C10	0.4048 (10)	0.3211 (4)	0.0447 (4)	0.0295 (13)
H10	0.3198	0.2886	0.0143	0.035*
C11	0.3160 (9)	0.3310 (4)	0.1362 (4)	0.0251 (11)
H11	0.1696	0.3060	0.1678	0.030*
C12	0.4408 (8)	0.3775 (3)	0.1818 (4)	0.0189 (10)
C13	0.4016 (8)	0.4665 (3)	0.3027 (4)	0.0188 (10)
C14	0.2414 (9)	0.4979 (4)	0.3679 (4)	0.0263 (12)
H14	0.0979	0.4665	0.3910	0.032*
C15	0.2932 (9)	0.5750 (4)	0.3988 (4)	0.0276 (12)
H15	0.1866	0.5946	0.4450	0.033*
C16	0.4979 (10)	0.6237 (4)	0.3631 (4)	0.0282 (12)
H16	0.5317	0.6764	0.3849	0.034*
C17	0.6555 (9)	0.5955 (4)	0.2950 (4)	0.0239 (11)
H17	0.7945	0.6305	0.2684	0.029*
C18	0.6075 (8)	0.5159 (4)	0.2663 (4)	0.0196 (10)
C19	−0.0747 (9)	0.9019 (4)	0.0395 (4)	0.0258 (11)
C20	0.1095 (8)	0.9257 (4)	0.0749 (4)	0.0217 (11)
C21	0.1797 (9)	1.0245 (4)	0.0344 (4)	0.0279 (12)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
F1	0.0293 (18)	0.0184 (16)	0.059 (2)	−0.0042 (13)	−0.0154 (16)	0.0031 (15)
F2	0.060 (3)	0.0292 (18)	0.089 (3)	0.0062 (17)	−0.059 (2)	−0.0199 (19)
F3	0.0324 (19)	0.0148 (16)	0.100 (3)	−0.0028 (14)	−0.012 (2)	−0.0077 (18)
F4	0.043 (2)	0.035 (2)	0.136 (4)	0.0112 (17)	−0.059 (3)	−0.041 (2)
F5	0.0343 (19)	0.0258 (17)	0.063 (2)	−0.0095 (14)	−0.0184 (17)	−0.0078 (16)
F6	0.052 (2)	0.0340 (19)	0.087 (3)	−0.0049 (17)	−0.050 (2)	−0.016 (2)
I1	0.0433 (2)	0.0354 (2)	0.0318 (2)	0.02333 (17)	−0.02422 (17)	−0.01896 (17)
I2	0.0745 (3)	0.0274 (2)	0.0203 (2)	0.02422 (19)	−0.01926 (19)	−0.00903 (15)
I3	0.0379 (2)	0.0299 (2)	0.0274 (2)	0.00992 (15)	−0.01568 (16)	−0.01382 (15)
N1	0.017 (2)	0.020 (2)	0.025 (2)	−0.0040 (17)	0.0037 (17)	−0.0054 (18)
S1	0.0176 (6)	0.0268 (7)	0.0218 (6)	0.0018 (5)	−0.0024 (5)	−0.0102 (5)
C1	0.020 (3)	0.025 (3)	0.018 (3)	0.011 (2)	−0.006 (2)	−0.010 (2)
C2	0.019 (2)	0.016 (2)	0.024 (3)	−0.0019 (19)	−0.001 (2)	−0.004 (2)
C3	0.021 (3)	0.026 (3)	0.030 (3)	0.004 (2)	−0.014 (2)	−0.012 (2)
C4	0.024 (3)	0.019 (2)	0.014 (2)	0.005 (2)	−0.002 (2)	−0.006 (2)
C5	0.016 (3)	0.016 (2)	0.042 (3)	−0.001 (2)	0.004 (2)	−0.011 (2)
C6	0.021 (3)	0.022 (3)	0.054 (4)	0.004 (2)	−0.016 (3)	−0.020 (3)
C7	0.023 (3)	0.013 (2)	0.018 (2)	0.0047 (19)	−0.008 (2)	−0.0040 (19)
C8	0.029 (3)	0.017 (2)	0.020 (3)	0.004 (2)	−0.002 (2)	−0.003 (2)
C9	0.049 (4)	0.021 (3)	0.020 (3)	0.009 (2)	−0.011 (3)	−0.008 (2)
C10	0.043 (3)	0.014 (2)	0.034 (3)	0.002 (2)	−0.019 (3)	−0.006 (2)
C11	0.027 (3)	0.012 (2)	0.031 (3)	0.000 (2)	−0.009 (2)	0.000 (2)
C12	0.022 (3)	0.010 (2)	0.019 (3)	0.0025 (19)	−0.003 (2)	0.0003 (19)
C13	0.019 (2)	0.015 (2)	0.016 (2)	0.0025 (19)	−0.0028 (19)	0.0007 (19)
C14	0.026 (3)	0.024 (3)	0.021 (3)	0.003 (2)	0.003 (2)	−0.001 (2)
C15	0.029 (3)	0.026 (3)	0.020 (3)	0.003 (2)	0.008 (2)	−0.004 (2)
C16	0.041 (3)	0.023 (3)	0.023 (3)	0.010 (2)	−0.009 (2)	−0.011 (2)
C17	0.026 (3)	0.024 (3)	0.020 (3)	0.005 (2)	−0.007 (2)	−0.005 (2)
C18	0.023 (3)	0.020 (2)	0.015 (2)	0.005 (2)	−0.003 (2)	−0.005 (2)
C19	0.026 (3)	0.023 (3)	0.030 (3)	−0.003 (2)	−0.004 (2)	−0.010 (2)
C20	0.021 (3)	0.029 (3)	0.020 (3)	0.006 (2)	−0.007 (2)	−0.014 (2)
C21	0.025 (3)	0.031 (3)	0.036 (3)	−0.002 (2)	−0.016 (2)	−0.017 (3)

Geometric parameters (Å, º)

F1—C2	1.338 (5)	C4—C5	1.365 (7)
F2—C3	1.342 (6)	C5—C6	1.373 (8)
F2—F2^i	2.560 (6)	C7—C12	1.390 (7)
F3—C5	1.345 (6)	C7—C8	1.394 (7)
F4—C6	1.339 (6)	C8—C9	1.382 (8)
F5—C19	1.339 (6)	C8—H8	0.9500
F6—C21	1.342 (6)	C9—C10	1.376 (8)
I1—C1	2.076 (5)	C9—H9	0.9500
I1—C10^ii	3.532 (5)	C10—C11	1.387 (8)
I1—C9^ii	3.615 (5)	C10—H10	0.9500
I1—C11^ii	3.676 (5)	C11—C12	1.392 (7)
I2—C4	2.085 (5)	C11—H11	0.9500
I2—N1	3.323 (4)	C13—C18	1.390 (7)
I2—C13	3.620 (5)	C13—C14	1.400 (7)
I2—S1	3.7597 (13)	C14—C15	1.384 (8)
I3—C20	2.082 (5)	C14—H14	0.9500
I3—C16	3.324 (5)	C15—C16	1.379 (8)
I3—C15	3.630 (5)	C15—H15	0.9500
N1—C13	1.409 (6)	C16—C17	1.396 (7)
N1—C12	1.416 (6)	C16—H16	0.9500
N1—H1	0.7946	C17—C18	1.391 (7)
S1—C18	1.771 (5)	C17—H17	0.9500
S1—C7	1.773 (5)	C19—C21^iii	1.377 (7)
C1—C2	1.378 (7)	C19—C20	1.386 (7)
C1—C6	1.386 (7)	C20—C21	1.371 (7)
C2—C3	1.378 (7)	C21—C19^iii	1.377 (7)
C3—C4	1.380 (7)
C3—F2—F2^i	161.6 (4)	C10—C9—C8	120.4 (5)
C1—I1—C10^ii	169.12 (16)	C10—C9—H9	119.8
C1—I1—C9^ii	159.53 (17)	C8—C9—H9	119.8
C10^ii—I1—C9^ii	22.16 (13)	C9—C10—C11	120.2 (5)
C1—I1—C11^ii	147.14 (15)	C9—C10—H10	119.9
C10^ii—I1—C11^ii	22.06 (12)	C11—C10—H10	119.9
C9^ii—I1—C11^ii	38.34 (13)	C10—C11—C12	120.2 (5)
C4—I2—N1	168.03 (15)	C10—C11—H11	119.9
C4—I2—C13	158.94 (15)	C12—C11—H11	119.9
N1—I2—C13	22.91 (10)	C7—C12—C11	119.2 (5)
C4—I2—S1	142.06 (14)	C7—C12—N1	120.0 (4)
N1—I2—S1	49.90 (7)	C11—C12—N1	120.7 (4)
C13—I2—S1	43.68 (8)	C18—C13—C14	119.6 (5)
C20—I3—C16	176.76 (18)	C18—C13—N1	120.4 (4)
C20—I3—C15	154.56 (17)	C14—C13—N1	119.9 (4)
C16—I3—C15	22.33 (13)	C18—C13—I2	87.1 (3)
C13—N1—C12	121.0 (4)	C14—C13—I2	114.2 (3)
C13—N1—I2	90.5 (3)	N1—C13—I2	66.6 (2)
C12—N1—I2	104.6 (3)	C15—C14—C13	119.7 (5)
C13—N1—H1	113.3	C15—C14—H14	120.2
C12—N1—H1	109.3	C13—C14—H14	120.2
I2—N1—H1	117.1	C16—C15—C14	120.7 (5)
C18—S1—C7	100.7 (2)	C16—C15—I3	66.3 (3)
C18—S1—I2	78.08 (16)	C14—C15—I3	107.4 (3)
C7—S1—I2	88.39 (16)	C16—C15—H15	119.6
C2—C1—C6	117.2 (5)	C14—C15—H15	119.6
C2—C1—I1	120.7 (4)	I3—C15—H15	96.0
C6—C1—I1	122.1 (4)	C15—C16—C17	120.1 (5)
F1—C2—C3	118.9 (4)	C15—C16—I3	91.4 (3)
F1—C2—C1	120.3 (4)	C17—C16—I3	95.2 (3)
C3—C2—C1	120.9 (5)	C15—C16—H16	120.0
F2—C3—C2	117.8 (5)	C17—C16—H16	120.0
F2—C3—C4	120.5 (4)	I3—C16—H16	83.4
C2—C3—C4	121.7 (5)	C18—C17—C16	119.5 (5)
C5—C4—C3	117.3 (4)	C18—C17—H17	120.3
C5—C4—I2	122.6 (4)	C16—C17—H17	120.3
C3—C4—I2	120.1 (4)	C13—C18—C17	120.4 (5)
F3—C5—C4	119.7 (5)	C13—C18—S1	120.3 (4)
F3—C5—C6	118.6 (5)	C17—C18—S1	119.1 (4)
C4—C5—C6	121.7 (5)	F5—C19—C21^iii	119.4 (5)
F4—C6—C5	118.8 (5)	F5—C19—C20	119.9 (5)
F4—C6—C1	119.9 (5)	C21^iii—C19—C20	120.6 (5)
C5—C6—C1	121.3 (5)	C21—C20—C19	117.5 (5)
C12—C7—C8	120.2 (5)	C21—C20—I3	122.6 (4)
C12—C7—S1	120.5 (4)	C19—C20—I3	119.9 (4)
C8—C7—S1	119.2 (4)	F6—C21—C20	120.0 (5)
C9—C8—C7	119.7 (5)	F6—C21—C19^iii	118.2 (5)
C9—C8—H8	120.1	C20—C21—C19^iii	121.9 (5)
C7—C8—H8	120.1

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