Hydrogen-bonding one-dimensional chains containing the R₄²(8) motif in the ammonium salts 1-naphthyl­ammonium iodide and naphthalene-1,8-diyldiammonium diiodide

In 1-naphthyl­ammonium iodide, C₁₀H₁₀N⁺·I^-, and naphthalene-1,8-diyldiammonium diiodide, C₁₀H₁₂N₂²⁺·2I^-, the pre­dominant hydrogen-bonding pattern can be described using the graph-set notation R₄²(8). This is the first report of a structure of a diprotonated naphthalene-1,8-diyldiammonium salt.

S1. Comment

As part of a continuing investigation into the hydrogen-bonding motifs exhibited by simple organic ammonium halide salts, the crystal structures of two naphthalene ammonium salts are reported (Lemmerer & Billing, 2006a,b,c,d, 2007). The unprotonated cases of the title compounds have been reported previously, viz. 1,8-diaminonaphthalene twice [Cambridge Structural Database (CSD; Version 5.29, November 2007 release; Allen, 2002) refcodes JISVEM and JISVEM01; Llamas-Saiz et al., 1991; Basaran et al., 1993) and 1-naphthylamine once (ZZZOZQ; Kitaigorodskii, 1945). In the diaminonaphthalene case, mono-protonated salts are more common. Counter-ions in these structures include dichloroacetate (LECCIF; Basaran et al., 1993), trichloroacetate (LECCOL; Basaran et al., 1993) and maleate (YEWRIB; Bartoszak et al., 1995). No diprotonated 1,8–diaminonaphthalene ammonium salts are reported in the CSD. The 1-ammoniumnaphthalene salts have two different counter-ions, namely a cyclohexaphosphate (HUNDAV; Nasr et al., 2001), cyclohexaphosphate and 1,6-diammonium hexane together (MAVQEF; Marouani et al., 1998), and trichloroacetate (LECCUR; Basaran et al., 1993) In the current report, we compare the packing arrangements and hydrogen-bonding motifs exhibited by the two title compounds, (I) amd (II).

The molecular structure of (I) and the packing arrangement in the unit cell viewed along the c axis are shown in Figs. 1(a) and 2, respectively. All the C atoms and the N atom lie in a well defined plane and deviate from it by no more than 0.051 (8) Å. The structure consists of ionic pillars, extending along the c axis, that are surrounded by a hydrocarbon framework. There are two complete ionic pillars per unit cell, each centred around inversion centres, one at the centre of the unit cell (1/2, 1/2, z), and another at the four corners of the unit cell, at (0, 0, z), (1, 0, z), (0, 1, z) and (1, 1, z). The ionic pillars consist of four I^- anions and four NH₃⁺ ammonium groups, arranged tetrahedrally on the vertices of a distorted cube (Fig. 3). Each ionic pillar is surrounded by four naphthalene molecules that interact with the π system of adjacent naphthalene molecules by C—H···π interactions (Fig. 2). The H7···Cg2 distance is 2.94 Å and the C7—H7···Cg2 angle is 130°, where Cg2 is the centroid of the aromatic ring described by atoms C4B, C4A, C5, C6, C7 and C8.

The hydrogen-bonding interactions within the ionic pillar form extended one-dimensional chains (Fig. 4 and Table 1) consisting of four unique hydrogen-bonded rings. The basic hydrogen-bonding scheme can be described as the ring motif R₄²(8) when using graph-set notation (Bernstein et al., 1995). The first ring, designated R', describes the sequence N1—H1C···I1···H1A—N1—H1C···I1···H1A–. The H1C···I1 and H1A···I1 distances are 2.68 and 2.69 Å, respectively. The second ring, R'', is adjacent to R' and contains the sequence N1—H1B···I1···H1A—N1—H1B···I1···H1A–. The H1B···I1 and H1A···I1 distances are 3.13 and 2.69 Å, respectively. Atom H1A is common to both rings. These two rings lie parallel to the ac plane and extend in the direction of the crystallographic c axis. Two of these joined rings are present in the ionic pillar and are joined along the crystallographic b direction by a third hydrogen-bonded ring, R''', with the sequence N1—H1A···I1···H1B—N1—H1A···I1···H1B–. The H1A···I1 and H1B···I1 distances are 2.69 and 3.01 Å, respectively. The last ring, R'''', lies parallel to the ab plane and has a different bonding motif. R'''' has a bifurcated hydrogen bond and hence the notation is R²₃(6). The sequence is N1—H1B···I1···H1B···I1···H1C–. All four are combined in the form of a distorted cube, with one face each of R' and R'', and two faces each of R''' and R'''' (Fig. 4). The N1 donor and I1 acceptor atoms sit at the eight vertices of the distorted cube.

The atomic numbering scheme of (II) is shown in Fig. 1(b). Here, the crystal structure has a bidimensional arrangement, in which a double layer of 1,8-diammoniumnaphthalene cations is embedded between two consecutive ionic layers, forming an alternating hydrocarbon–ionic structure along the c axis (Fig. 5). The X-ray structure reveals that the N atoms are slightly bent out of the plane of the C atoms of the naphthalene ring. Atoms N1 and N2 deviate from the plane defined by atoms C1–C8 by 0.214 (6) and -0.278 (6) Å, respectively. Associated with this is a dihedral angle of 7.7 (2)° between the two joined rings, common edge C4A and C4B. The N atoms themselves lean away from each other, as seen in Fig. 1(b). This bending has been described in the literature as the peri interaction (Balasubramaniyan, 1966) and is also observed in the crystal structure of the unprotonated 1,8-diaminonaphthalene molecule (Llamas-Saiz et al., 1991). In the latter case, the repulsion is partly countered by an attractive intramolecular hydrogen bond, and the N···N distances are 2.72 and 2.74 Å, respectively, for the two molecules in the asymmetric unit. In the mono-protonated salts, the distances are 2.72 Å for both LECCIF and LECCOL (Basaran et al., 1993) and 2.67 Å for YEWRIB (Bartoszak et al., 1995). Compound (II) has no intramolecular hydrogen bond and the N1···N2 distance is subsequently longer at 2.92 (1) Å.

The two N atoms on the 1,8-diammoniumnaphthalene cation again form hydrogen bonds to the I2 atoms using the same R₄²(8) ring motif seen in (I). Atom N1 has the following sequence of hydrogen bonds: N1—H1B···I2···H1C—N1—H1B···I2···H1C–; similarly, atom N2 has the sequence N2—H2C···I2···H2A—N2—H2C···I2···H2A–. The rings are centrosymmetric, being centred around (1/2, 0, 1/2) and (1/2, 1/2, 1/2). These two rings have the same acceptor atom I2. One final hydrogen-bonded ring is found in the structure. This ring too has an R₄²(8) motif but has both I1 and I2 as acceptor atoms and N1 and N2 as donor atoms: N1—H1A···I1···H2B—N2—H2A···I2···H1B– (Figs. 1 and 6). These three rings also describe extended one-dimensional chains in the b direction (Fig. 6).

Related literature

For related literature, see: Allen (2002); Balasubramaniyan (1966); Bartoszak et al. (1995); Basaran et al. (1993); Bernstein et al. (1995); Kitaigorodskii (1945); Lemmerer & Billing (2006a, 2006b, 2006c, 2006d, 2007); Llamas-Saiz, Foces-Foces, Molina, Alajarin, Vidal, Claramunt & Elguero (1991); Marouani et al. (1998); Nasr et al. (2001).

S2. Experimental

All chemicals were purchased from commercial sources and used as received. Compound (I) was prepared by slowly evaporating a solution of 1-aminonaphthalene (0.015 g, 0.105 mmol) in 5 ml of 48% aqueous HI. Compound (II) was prepared by slow cooling of a solution containing 1,8-diaminonaphthalene (0.010 g, 0.063 mmol) in 7 ml of 48% aqueous HI. The solution was kept at 373 K for 12 h and then cooled to room temperature at a rate of 2 K h^-1.

S3. Refinement

For both compounds, all H atoms were refined using a riding model, with C—H distances of 0.93 Å and N—H distances of 0.89 Å, and with U_iso(H) values of 1.2U_eq(C) or 1.5U_eq(N). The highest residual peak was 1.25 Å from atom H7 in (I) and 1.21 Å from I1 in (II).

Computing details

For both compounds, data collection: SMART (Bruker, 1998); cell refinement: SAINT-Plus (Bruker, 1999); data reduction: SAINT-Plus (Bruker, 1999); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997) and DIAMOND (Brandenburg, 1999); software used to prepare material for publication: WinGX (Farrugia, 1999) and PLATON (Spek, 2003).

Figures

	Fig. 1. The asymmetric units of (a) (I) and (b) (II). Displacement ellipsoids are shown at the 50% probability level and H atoms are shown as small spheres of arbitrary radii.
	Fig. 2. The packing of (I). Intermolecular hydrogen bonds within the ionic pillars form chains along the c axis, and C—H···π interactions join the naphthalene framework along the c axis. H atoms have been omitted for clarity, except those involved in hydrogen bonds and C—H···π interactions (shown as dashed lines).
	Fig. 3. A perspective view of an ionic pillar and the one-dimensional chain of hydrogen bonds of (I).
	Fig. 4. A magnified view of the one-dimensional chain of hydrogen bonds of (I). Only the C atoms to which the N atoms are attached are shown. [Symmetry codes: (i) -x + 1, y, -z + 1/2; (ii) x, -y + 1, z + 1/2; (iii) x, y, z + 1.] The schematic shows the four different hydrogen-bonded rings, forming a distorted cube.
	Fig. 5. , The packing of (II). H atoms have been omitted for clarity.
	Fig. 6. A magnified view of the hydrogen-bonded chain of (II). The intermolecular hydrogen bonds that form chains along the c axis are shown as dashed lines. H atoms have been omitted for clarity. [Symmetry codes: (i) -x + 1, -y + 1, -z + 1; (ii) -x + 1, -y, -z + 1.]

(I) 1-naphthylammonium iodide

Crystal data

C10H10N^+·I^−	F(000) = 1040
Mr = 271.09	Dx = 1.799 Mg m^−3
Orthorhombic, Pbcn	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2n 2ab	Cell parameters from 891 reflections
a = 24.259 (4) Å	θ = 2.5–28.3°
b = 11.469 (2) Å	µ = 3.15 mm^−1
c = 7.1937 (12) Å	T = 293 K
V = 2001.5 (6) Å^3	Plate, colourless
Z = 8	0.5 × 0.23 × 0.09 mm

Data collection

Bruker SMART 1K CCD area-detector diffractometer	1646 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.077
ω scans	θmax = 25.5°, θmin = 1.7°
Absorption correction: integration XPREP (Bruker, 1999)	h = −29→28
Tmin = 0.293, Tmax = 0.706	k = −13→12
10172 measured reflections	l = −8→8
1870 independent reflections

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)] = 0.055	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.139	H-atom parameters constrained
S = 1.33	w = 1/[σ^2(Fo^2) + (0.0416P)^2 + 14.1602P] where P = (Fo^2 + 2Fc^2)/3
1870 reflections	(Δ/σ)max < 0.001
110 parameters	Δρmax = 1.05 e Å^−3
0 restraints	Δρmin = −1.33 e Å^−3

Special details

Experimental. Numerical integration absorption corrections based on indexed crystal faces were applied using the XPREP routine (Bruker, 1999)

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 (Ų)

	x	y	z	Uiso*/Ueq
C1	0.4109 (3)	0.2122 (7)	0.5144 (8)	0.0269 (15)
C2	0.4468 (3)	0.1292 (6)	0.5712 (9)	0.0305 (16)
H2	0.4839	0.1476	0.5861	0.037*
C3	0.4283 (3)	0.0158 (7)	0.6077 (10)	0.0340 (17)
H3	0.4533	−0.041	0.6454	0.041*
C4	0.3742 (3)	−0.0119 (7)	0.5884 (10)	0.0359 (18)
H4	0.3623	−0.0874	0.613	0.043*
C4A	0.3352 (3)	0.0750 (6)	0.5302 (9)	0.0292 (16)
C4B	0.3544 (3)	0.1901 (6)	0.4866 (9)	0.0260 (15)
C5	0.2790 (4)	0.0478 (8)	0.5025 (11)	0.044 (2)
H5	0.2663	−0.0265	0.5316	0.053*
C6	0.2426 (4)	0.1297 (8)	0.4330 (13)	0.044 (2)
H6	0.2057	0.1108	0.4139	0.052*
C7	0.2625 (3)	0.2428 (7)	0.3914 (11)	0.0334 (17)
H7	0.2382	0.2979	0.3439	0.04*
C8	0.3154 (3)	0.2732 (7)	0.4184 (10)	0.0308 (16)
H8	0.3267	0.3489	0.3924	0.037*
N1	0.4314 (3)	0.3316 (6)	0.4796 (8)	0.0305 (14)
H1A	0.4678	0.3336	0.4966	0.046*
H1B	0.4153	0.381	0.5579	0.046*
H1C	0.4237	0.3522	0.3632	0.046*
I1	0.422284 (19)	0.36053 (4)	−0.00920 (6)	0.0311 (2)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
C1	0.040 (4)	0.027 (4)	0.014 (3)	−0.002 (3)	0.000 (3)	−0.001 (3)
C2	0.043 (4)	0.034 (4)	0.015 (3)	0.007 (3)	−0.003 (3)	−0.002 (3)
C3	0.048 (5)	0.030 (4)	0.024 (3)	0.016 (4)	0.000 (3)	0.003 (3)
C4	0.063 (5)	0.021 (4)	0.023 (3)	0.002 (4)	0.011 (4)	0.002 (3)
C4A	0.045 (4)	0.028 (4)	0.015 (3)	−0.005 (3)	0.009 (3)	−0.003 (3)
C4B	0.038 (4)	0.023 (3)	0.017 (3)	−0.001 (3)	0.008 (3)	−0.006 (3)
C5	0.055 (5)	0.042 (5)	0.035 (4)	−0.016 (4)	0.019 (4)	−0.008 (4)
C6	0.035 (4)	0.055 (6)	0.041 (4)	−0.009 (4)	0.003 (4)	−0.010 (4)
C7	0.021 (4)	0.043 (4)	0.036 (4)	0.007 (3)	0.001 (3)	−0.007 (3)
C8	0.038 (4)	0.027 (4)	0.027 (4)	0.006 (3)	0.004 (3)	−0.002 (3)
N1	0.036 (3)	0.029 (3)	0.026 (3)	−0.006 (3)	−0.002 (3)	−0.004 (3)
I1	0.0370 (3)	0.0336 (3)	0.0227 (3)	0.0007 (2)	0.0002 (2)	−0.00115 (19)

Geometric parameters (Å, º)

C1—C2	1.353 (11)	C4B—C8	1.430 (10)
C1—C4B	1.407 (10)	C5—C6	1.384 (13)
C1—N1	1.480 (10)	C5—H5	0.93
C2—C3	1.401 (11)	C6—C7	1.416 (12)
C2—H2	0.93	C6—H6	0.93
C3—C4	1.358 (11)	C7—C8	1.343 (10)
C3—H3	0.93	C7—H7	0.93
C4—C4A	1.436 (11)	C8—H8	0.93
C4—H4	0.93	N1—H1A	0.89
C4A—C5	1.413 (12)	N1—H1B	0.89
C4A—C4B	1.435 (10)	N1—H1C	0.89
C2—C1—C4B	122.9 (7)	C6—C5—C4A	121.2 (8)
C2—C1—N1	119.0 (7)	C6—C5—H5	119.4
C4B—C1—N1	118.1 (6)	C4A—C5—H5	119.4
C1—C2—C3	120.2 (7)	C5—C6—C7	118.7 (7)
C1—C2—H2	119.9	C5—C6—H6	120.7
C3—C2—H2	119.9	C7—C6—H6	120.7
C4—C3—C2	120.5 (7)	C8—C7—C6	122.2 (7)
C4—C3—H3	119.8	C8—C7—H7	118.9
C2—C3—H3	119.8	C6—C7—H7	118.9
C3—C4—C4A	120.3 (7)	C7—C8—C4B	120.6 (7)
C3—C4—H4	119.9	C7—C8—H8	119.7
C4A—C4—H4	119.9	C4B—C8—H8	119.7
C5—C4A—C4B	119.0 (7)	C1—N1—H1A	109.5
C5—C4A—C4	121.5 (7)	C1—N1—H1B	109.5
C4B—C4A—C4	119.3 (7)	H1A—N1—H1B	109.5
C1—C4B—C8	125.0 (7)	C1—N1—H1C	109.5
C1—C4B—C4A	116.7 (7)	H1A—N1—H1C	109.5
C8—C4B—C4A	118.3 (7)	H1B—N1—H1C	109.5
C4B—C1—C2—C3	−0.9 (10)	C4—C4A—C4B—C1	−3.5 (9)
N1—C1—C2—C3	179.1 (6)	C5—C4A—C4B—C8	0.6 (9)
C1—C2—C3—C4	−0.7 (11)	C4—C4A—C4B—C8	176.3 (6)
C2—C3—C4—C4A	0.0 (11)	C4B—C4A—C5—C6	0.6 (11)
C3—C4—C4A—C5	177.7 (7)	C4—C4A—C5—C6	−175.1 (7)
C3—C4—C4A—C4B	2.1 (10)	C4A—C5—C6—C7	−0.7 (12)
C2—C1—C4B—C8	−176.9 (7)	C5—C6—C7—C8	−0.4 (12)
N1—C1—C4B—C8	3.1 (10)	C6—C7—C8—C4B	1.6 (11)
C2—C1—C4B—C4A	2.9 (9)	C1—C4B—C8—C7	178.1 (7)
N1—C1—C4B—C4A	−177.1 (5)	C4A—C4B—C8—C7	−1.7 (10)
C5—C4A—C4B—C1	−179.2 (6)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1A···I1^i	0.89	2.69	3.570 (6)	172
N1—H1B···I1^ii	0.89	3.01	3.538 (7)	120
N1—H1B···I1^iii	0.89	3.13	3.699 (6)	124
N1—H1C···I1	0.89	2.68	3.539 (6)	162

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

(II) naphthalene-1,8-diyldiammonium diiodide

Crystal data

C10H12N2^2+·2I^−	Z = 2
Mr = 414.02	F(000) = 384
Triclinic, P1	Dx = 2.214 Mg m^−3
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 7.2529 (13) Å	Cell parameters from 756 reflections
b = 9.1586 (17) Å	θ = 2.7–27.9°
c = 10.897 (2) Å	µ = 5.03 mm^−1
α = 68.082 (3)°	T = 293 K
β = 75.764 (3)°	Block, brown
γ = 68.867 (3)°	0.28 × 0.2 × 0.04 mm
V = 621.2 (2) Å^3

Data collection

Bruker SMART 1K CCD area-detector diffractometer	1901 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.050
ω scans	θmax = 25.5°, θmin = 2.0°
Absorption correction: integration XPREP (Bruker, 1999)	h = −8→8
Tmin = 0.119, Tmax = 0.814	k = −11→10
3479 measured reflections	l = −11→13
2288 independent reflections

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)] = 0.041	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.114	H-atom parameters constrained
S = 1.03	w = 1/[σ^2(Fo^2) + (0.0785P)^2] where P = (Fo^2 + 2Fc^2)/3
2288 reflections	(Δ/σ)max < 0.001
129 parameters	Δρmax = 1.44 e Å^−3
0 restraints	Δρmin = −1.54 e Å^−3

Special details

Experimental. Numerical integration absorption corrections based on indexed crystal faces were applied using the XPREP routine (Bruker, 1999)

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 (Ų)

	x	y	z	Uiso*/Ueq
C1	0.2687 (9)	0.3364 (7)	0.8021 (6)	0.0321 (12)
C2	0.2656 (10)	0.4149 (9)	0.8864 (7)	0.0431 (16)
H2	0.2757	0.5215	0.8515	0.052*
C3	0.2476 (11)	0.3392 (10)	1.0253 (7)	0.0520 (18)
H3	0.2388	0.3963	1.0824	0.062*
C4	0.2433 (10)	0.1802 (10)	1.0741 (6)	0.0465 (17)
H4	0.2374	0.127	1.1657	0.056*
C4A	0.2478 (8)	0.0933 (8)	0.9886 (6)	0.0357 (14)
C4B	0.2517 (8)	0.1729 (7)	0.8480 (6)	0.0295 (12)
C5	0.2467 (9)	−0.0741 (9)	1.0438 (7)	0.0466 (17)
H5	0.2465	−0.1253	1.1353	0.056*
C6	0.2460 (11)	−0.1601 (9)	0.9676 (7)	0.0489 (17)
H6	0.2516	−0.2707	1.0054	0.059*
C7	0.2366 (10)	−0.0816 (8)	0.8303 (7)	0.0423 (15)
H7	0.229	−0.1388	0.7778	0.051*
C8	0.2386 (9)	0.0799 (7)	0.7730 (6)	0.0313 (12)
N1	0.2955 (8)	0.4271 (6)	0.6597 (5)	0.0346 (11)
H1A	0.1853	0.4513	0.6248	0.052*
H1B	0.3977	0.3653	0.6187	0.052*
H1C	0.32	0.52	0.6489	0.052*
N2	0.2103 (8)	0.1536 (6)	0.6314 (5)	0.0368 (12)
H2A	0.3155	0.1862	0.5843	0.055*
H2B	0.1011	0.24	0.6214	0.055*
H2C	0.1973	0.0791	0.6026	0.055*
I1	−0.21945 (6)	0.50509 (5)	0.67326 (4)	0.03958 (18)
I2	0.71599 (6)	0.15113 (5)	0.52851 (4)	0.04057 (18)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
C1	0.033 (3)	0.033 (3)	0.027 (3)	−0.008 (3)	−0.004 (2)	−0.008 (2)
C2	0.049 (4)	0.048 (4)	0.035 (4)	−0.017 (3)	−0.002 (3)	−0.017 (3)
C3	0.057 (4)	0.073 (5)	0.032 (4)	−0.015 (4)	−0.005 (3)	−0.028 (4)
C4	0.048 (4)	0.070 (5)	0.019 (3)	−0.021 (4)	−0.005 (3)	−0.007 (3)
C4A	0.027 (3)	0.043 (4)	0.026 (3)	−0.004 (3)	−0.006 (3)	−0.003 (3)
C4B	0.024 (3)	0.034 (3)	0.027 (3)	−0.006 (2)	−0.001 (2)	−0.010 (2)
C5	0.038 (3)	0.047 (4)	0.031 (4)	−0.010 (3)	−0.006 (3)	0.011 (3)
C6	0.053 (4)	0.036 (4)	0.040 (4)	−0.016 (3)	−0.005 (3)	0.007 (3)
C7	0.052 (4)	0.037 (3)	0.036 (4)	−0.019 (3)	0.004 (3)	−0.010 (3)
C8	0.036 (3)	0.032 (3)	0.022 (3)	−0.012 (3)	−0.004 (2)	−0.001 (2)
N1	0.049 (3)	0.028 (2)	0.024 (3)	−0.016 (2)	0.000 (2)	−0.003 (2)
N2	0.056 (3)	0.034 (3)	0.022 (3)	−0.019 (3)	−0.004 (2)	−0.006 (2)
I1	0.0487 (3)	0.0442 (3)	0.0232 (3)	−0.0154 (2)	−0.00624 (19)	−0.00518 (19)
I2	0.0446 (3)	0.0342 (3)	0.0411 (3)	−0.0093 (2)	−0.0034 (2)	−0.0136 (2)

Geometric parameters (Å, º)

C1—C2	1.353 (8)	C5—H5	0.93
C1—C4B	1.432 (8)	C6—C7	1.404 (9)
C1—N1	1.464 (7)	C6—H6	0.93
C2—C3	1.405 (10)	C7—C8	1.378 (9)
C2—H2	0.93	C7—H7	0.93
C3—C4	1.360 (10)	C8—N2	1.468 (7)
C3—H3	0.93	N1—H1A	0.89
C4—C4A	1.423 (9)	N1—H1B	0.89
C4—H4	0.93	N1—H1C	0.89
C4A—C5	1.424 (9)	N2—H2A	0.89
C4A—C4B	1.428 (8)	N2—H2B	0.89
C4B—C8	1.421 (8)	N2—H2C	0.89
C5—C6	1.344 (10)
C2—C1—C4B	122.6 (6)	C5—C6—C7	119.5 (6)
C2—C1—N1	116.0 (5)	C5—C6—H6	120.3
C4B—C1—N1	121.4 (5)	C7—C6—H6	120.3
C1—C2—C3	121.6 (7)	C8—C7—C6	120.3 (6)
C1—C2—H2	119.2	C8—C7—H7	119.9
C3—C2—H2	119.2	C6—C7—H7	119.9
C4—C3—C2	118.3 (6)	C7—C8—C4B	122.3 (6)
C4—C3—H3	120.9	C7—C8—N2	115.4 (5)
C2—C3—H3	120.9	C4B—C8—N2	122.1 (5)
C3—C4—C4A	121.6 (6)	C1—N1—H1A	109.5
C3—C4—H4	119.2	C1—N1—H1B	109.5
C4A—C4—H4	119.2	H1A—N1—H1B	109.5
C4—C4A—C5	119.7 (6)	C1—N1—H1C	109.5
C4—C4A—C4B	120.5 (6)	H1A—N1—H1C	109.5
C5—C4A—C4B	119.8 (6)	H1B—N1—H1C	109.5
C8—C4B—C4A	116.0 (5)	C8—N2—H2A	109.5
C8—C4B—C1	128.9 (5)	C8—N2—H2B	109.5
C4A—C4B—C1	115.1 (5)	H2A—N2—H2B	109.5
C6—C5—C4A	121.9 (6)	C8—N2—H2C	109.5
C6—C5—H5	119.1	H2A—N2—H2C	109.5
C4A—C5—H5	119.1	H2B—N2—H2C	109.5
C4B—C1—C2—C3	0.7 (10)	C2—C1—C4B—C4A	−4.9 (9)
N1—C1—C2—C3	−177.8 (6)	N1—C1—C4B—C4A	173.5 (5)
C1—C2—C3—C4	3.3 (11)	C4—C4A—C5—C6	178.4 (6)
C2—C3—C4—C4A	−2.8 (11)	C4B—C4A—C5—C6	−1.1 (10)
C3—C4—C4A—C5	178.9 (6)	C4A—C5—C6—C7	−3.0 (11)
C3—C4—C4A—C4B	−1.6 (10)	C5—C6—C7—C8	3.4 (11)
C4—C4A—C4B—C8	−174.8 (5)	C6—C7—C8—C4B	0.5 (10)
C5—C4A—C4B—C8	4.7 (8)	C6—C7—C8—N2	−174.8 (6)
C4—C4A—C4B—C1	5.3 (8)	C4A—C4B—C8—C7	−4.5 (9)
C5—C4A—C4B—C1	−175.2 (5)	C1—C4B—C8—C7	175.4 (6)
C2—C1—C4B—C8	175.2 (6)	C4A—C4B—C8—N2	170.6 (5)
N1—C1—C4B—C8	−6.4 (9)	C1—C4B—C8—N2	−9.5 (9)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1A···I1	0.89	2.74	3.517 (5)	146
N1—H1B···I2	0.89	2.68	3.568 (5)	172
N1—H1C···I2^i	0.89	2.87	3.615 (5)	143
N2—H2A···I2	0.89	2.74	3.556 (5)	153
N2—H2B···I1	0.89	2.82	3.668 (5)	161
N2—H2C···I2^ii	0.89	2.78	3.634 (5)	161

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