Enhanced third-order nonlinear optical properties determined in thin films using the Z-scan technique: bis­(μ-4,4′-oxy­diben­z­o­ato)bis­[(4′-phenyl-2,2′:6′,2′′-ter­pyri­dine)­cobalt(II)]

π-Conjugated organic materials exhibit high and tunable nonlinear optical (NLO) properties, and fast response times. 4′-Phenyl-2,2′:6′,2′′-terpyridine (PTP) is an important N-heterocyclic ligand involving π-conjugated systems, however, studies concerning the third-order NLO properties of terpyridine transition metal complexes are limited. The title binuclear ter­pyridine Co^II complex, bis­(μ-4,4′-oxydibenzoato)-κ³O,O′:O′′;κ³O′′:O,O′-bis­[(4′-phenyl-2,2′:6′,2′′-terpyridine-κ³N,N′,N′′)cobalt(II)], [Co₂(C₁₄H₈O₅)₂(C₂₁H₁₅N₃)₂], (1), has been synthesized under hydro­thermal conditions. In the crystal structure, each Co^II cation is surrounded by three N atoms of a PTP ligand and three O atoms, two from a bidentate and one from a symmetry-related monodentate 4,4′-oxy­dibenzoate (ODA²⁻) ligand, completing a distorted octa­hedral coordination geometry. Neighbouring [Co(PTP)]²⁺ units are bridged by ODA²⁻ ligands to form a ring-like structure. The third-order nonlinear optical (NLO) properties of (1) and PTP were determined in thin films using the Z-scan technique. The title compound shows a strong third-order NLO saturable absorption (SA), while PTP exhibits a third-order NLO reverse saturable absorption (RSA). The absorptive coefficient β of (1) is −37.3 × 10⁻⁷ m W⁻¹, which is larger than that (8.96 × 10⁻⁷ m W⁻¹) of PTP. The third-order NLO susceptibility χ⁽³⁾ values are calculated as 6.01 × 10⁻⁸ e.s.u. for (1) and 1.44 × 10⁻⁸ e.s.u. for PTP.

S1. Introduction

\ The design and synthesis of nonlinear optical materials has developed rapidly owing to applications of these materials in the fields of optical switching and optical limiting (Tang et al., 2013; Corredor et al., 2007; Denk et al., 1990). In recent years, π-conjugated organic materials have received considerable inter­est for their high nonlinear optical properties and fast response time (Brédas et al., 1994). These organic compounds have a large variety of structures and diverse electronic properties, which give an opportunity to tune the NLO properties of these compounds. Previous works showed that the introduction of transition metal ions into π-conjugated systems can effectively enhance the NLO properties of metal complexes. For instance, very recently, Torres and co-workers reported several extended π-conjugated ruthenium–zinc–porphyrin complexes with large third-order nonlinear optical absorption coefficients and refractive indices (Torres et al., 2015). 4'-Phenyl-2,2':6',2''-terpyridine (PTP) is an important N-heterocyclic ligand involving π-conjugated systems and has been widely used in the fields of biology, chemistry and materials. Recently, a few of terpyridine transition metal complexes with different biological and chemical activities were reported in the literature (Chen et al., 2013; Huang et al., 2013; Hussain et al., 2012; Maity et al., 2011; Roy et al., 2011; Field et al., 2007). However, studies concerning the third-order NLO properties of terpyridine transition metal complexes are limited. Based on the above considerations, we designed and synthesized a binuclear terpyridine Co^II complex bis­(µ-4,4'-oxydibenzoato)-κ³O,O':O;κ³O:\ O,O'-bis­[(4'-phenyl-2,2':6',2''-terpyridine-κ³N,\ N',N'')cobalt(II)], (1), with a 1:1 metal ion to ligand ratio by controlling the reaction conditions, and used the Z-scan technique to evaluate its NLO properties. Our results show that the nonlinear optical effect in (1) is much more pronounced than in PTP. We report here the crystal structure and third-order NLO properties of (1).

S2. Experimental

S2.1. Synthesis and crystallization

Co(CH₃COO)₂ (0.1 mmol, 0.018 g), 4,4'-oxybis(benzoic acid) (H₂ODA; 0.1 mmol, 0.026 g) and PTP (0.2 mmol, 0.031 g) were added to a mixture of distilled water (5 ml) and ethanol (5 ml), and the pH was adjusted to 5.0 by the addition of 0.2 M NaOH. The resulting mixture was stirred for 1 h, transferred into a Parr Teflon-lined stainless steel vessel, and then sealed and heated at 423 K for 3 d, followed by rapid cooling to ambient temperature. Red block-shaped crystals were collected manually, washed with distilled water and dried in air at ambient temperature (yield 86%, based on Co). Elemental analysis calculated for C₇₀H₄₆Co₂N₆O₁₀: C 67.31, N 6.73, H 3.71%; found: C 67.28, N 6.75, H, 3.73%.

S2.2. Refinement

Crystal data, data collection and structure refinement details are summarized in Table 1. C-bound H atoms were fixed geometrically and allowed to ride on their parent atom, with C—H = 0.93 Å and U_iso(H) = 1.2U_eq(C).

S2.3. Nonlinear optical measurements

To prepare the thin films, a fine powder of the sample were dispersed in ethanol using ultrasonic processing. The mixture was then spin-coated (1000 r.p.m., 30 s) onto cleaned quartz glass substrates and dried at room temperature for 2 h. The thickness of the film was measured with a thickness gauge [about 2 µm for (1)]. The nonlinear optical refraction and absorption were obtained with a linearly polarized laser light (7 ns, 10 Hz, 532 nm) generated from a mode-locked Q-switched Nd:YAG laser. The spatial profiles of the optical pulses are nearly Gaussian after being passed through a filter. The incident and transmitted pulsed energies are measured simultaneously by two energy detectors (RJP-765 Energy probes, laser precision, Laserprobe Corp), which were linked to a computer through an RS232 inter­face. The sample was mounted on a translation stage that was controlled by the computer to move along the z axis with respect to the focal point. An aperture of 0.5 mm radius was placed in front of the transmission detector and the transmittance was recorded as a function of the sample position on the z axis (closed-aperture Z-scan). For measuring the NLO absorption, the Z-dependent sample transmittance was taken without the aperture (open-aperture Z-scan).

S3. Re.s.u.lts and discussion

Complex (1) exhibits a discrete structure with the ratio of the PTP ligand and the Co^II ion being 1:1. Its asymmetric unit contains one Co^II cation, one PTP ligand and one ODA^2- dianion. As shown in Fig. 1, each Co^II atom is situated in a distorted o­cta­hedral coordination sphere, defined by three N atoms from one PPT ligand and by three O atoms from two different ODA^2- ligands. In this o­cta­hedral coordination sphere, atoms N1, N2, N3 and O3ⁱ [symmetry code: (i) -x+1, -y+1, -z] lie in the basal plane, while atoms O1 and O4ⁱ occupy the apical positions. The Co—N bond lengths (Table 2) are within the ranges reported for Co^II complexes (Zhang, Zhang et al., 2015). Of the Co—O bond lengths (Table 2), Co1—O4ⁱ is much longer than the others. The cis angles subtended at the Co^II atom by ligating atoms cover the range 58.69 (7)–110.16 (8)° (Table 2). Thus, the coordination geometry around the Co^II atom can be described as a distorted CoO₃N₃ o­cta­hedron. The PTP ligand chelates the Co^II atom and the ratio of metal ions and ligands is 1:1. Previous research showed that the ratio of metal ions and ligands plays an important role in the properties of the target compounds. For instance, Ma and coworker found that mononuclear terpyridine [Zn^II(PTP)]·X₂ (X = NO₃, CH₃COO, Cl and SO₄) complexes with a 1:1 ratio of metal ions and ligands exhibit promising in vitro tumour-inhibiting activities (Ma et al., 2010), which are higher than that of cisplatin against the following human tumor cell lines: promyelocyticfina leukaemia (HL-60), hepatocellula rcarcinoma (Bel-7402), gastric carcinoma (BGC-823) and nasopharyngeal carcinoma (KB). However, the mononuclear terpyridine [Zn^II(PTP)₂]·(NO₃)₂ complexes with a 1:2 ratio of metal ions and ligands do not bind DNA significantly (Sinha et al., 2015). They also reported four mononuclear terpyridine [Cu^II(PTP)]·X₂ (X = NO₃ and CH₃COO) complexes with a 1:1 ratio of metal ions and ligands which exhibit high catalytic activity, under mild conditions and in alkaline aqueous solution, for the aerobic oxidation of benzylic alcohols in combination with TEMPO (2,2,6,6-tetra­methyl­piperidinyl-1-oxyl radical) (Ma et al., 2014). Inter­estingly, the mononuclear terpyridine [Co^II(PTP)₂]·(NO₃)₂ complex with a 1:2 ratio of metal ions and ligands, can bind with the major groove of double helical DNA (Sinha et al., 2015).

In the title compound, (1), the ODA^2- ligand employs mono- and bidentate carboxyl­ate groups, adopting a µ₂-coordination mode, connecting two Co^II ions into a ring-like structure. The Co···Co separation within the ring is 11.76 (7) Å. There are two kinds of noncovalent inter­actions involved in the stabilization of the crystal lattice. In (1), the binuclear units are linked by a π–π inter­action of 3.57 (3) Å between the pyridine rings of the TPP ligands and a C—H··· π inter­action with distances of 3.74 (6) Å into a one-dimensional chain along the c axis. These one-dimensional chains are further connected by C—H··· π inter­actions, with distances of 3.68 (10) Å, into two-dimensional networks. Weak aromatic inter­actions have important effects on the properties and structures of compounds. Similar cases were encountered for comparable structures (Fu et al., 2015; McMurtrie & Dance, 2009). Field and co-workers (Field et al., 2012) found that [Pt(NCS)(PTP)]SbF₆ is porous, with empty channels stabilized by extended π–π inter­actions. When the compound was exposed to vapours of aceto­nitrile, the gaseous molecules were sorbed without loss of single crystallinity to give the adduct [Pt(NCS)(PTP)]SbF₆·CH₃CN. Similarly, this compound can sorb vapours of methanol and acetone without loss of single crystallinity to form [Pt(NCS)(PTP)]SbF₆·CH₃OH and [Pt(NCS)(PTP)]SbF₆·(CH₃)₂CO, respectively.

Although a few transition metal complexes and clusters with excellent third-order NLO properties have been reported, the data were obtained in solution (Zhang et al., 2007; Zhang, Liu & Lang, 2015). This is no suitable performance criterion for neat materials. In order to evaluate the third-order NLO performance of (1), films of (1) and TPP were prepared by spin coating and conducted open-aperture and closed-aperture Z-scan experiments. The open-aperture data of PTP and (1) are depicted in Figs. 3 and 4. It is obvious that PTP and (1) exhibit different third-order nonlinear optical absorption. From Fig. 3, the incident light irradiance is low in the far field, and the transmittance remains unchanged. As the sample moves towards the focal point, the incident light irradiance rises and the absorption increases. In the focus position, the absorption reaches the maximum. The open-aperture data clearly suggest the presence of reverse saturable absorption (RSA) behavior. The normalized transmittance drops to about 0.77. The corresponding third-order NLO absorptive coefficient β(MKS) is calculated to be 8.96 × 10 ^-7 m W^-1. It can be seen from Fig. 4 that the transmittance increases as the incident light irradiance rises. The normalized transmittance reaches the maximum at the focus position, which indicates that saturation absorption occurs. The β values is calculated to be -37.3 × 10 ^-7 m W^-1. The corresponding third-order NLO susceptibility χ⁽³⁾ are calculated as 6.01 × 10 ^-8 e.s.u. for (1) and 1.44 × 10 ^-8 e.s.u. for PTP. Our results show that the third-order NLO susceptibility χ⁽³⁾ of (1) is about four times that of PTP. This result is in agreement with the fact that the incorporation of transition metal atoms into π-conjugated organic systems may introduce more sublevels into the energy hierarchy, which is in favour of delocalization of the π-electron cloud. In addition, the charge-transfer nature of the metal–ligand bonds can also enhance the nonlinearity. The χ⁽³⁾ values of (1) and PTP in the solid state are much larger than those of other neat materials, such as neat inorganic semiconductors (about 10 ^-10 e.s.u.) and conjugated polymers (Chen et al., 2014; Liu et al., 2013).

Structure description

\ The design and synthesis of nonlinear optical materials has developed rapidly owing to applications of these materials in the fields of optical switching and optical limiting (Tang et al., 2013; Corredor et al., 2007; Denk et al., 1990). In recent years, π-conjugated organic materials have received considerable inter­est for their high nonlinear optical properties and fast response time (Brédas et al., 1994). These organic compounds have a large variety of structures and diverse electronic properties, which give an opportunity to tune the NLO properties of these compounds. Previous works showed that the introduction of transition metal ions into π-conjugated systems can effectively enhance the NLO properties of metal complexes. For instance, very recently, Torres and co-workers reported several extended π-conjugated ruthenium–zinc–porphyrin complexes with large third-order nonlinear optical absorption coefficients and refractive indices (Torres et al., 2015). 4'-Phenyl-2,2':6',2''-terpyridine (PTP) is an important N-heterocyclic ligand involving π-conjugated systems and has been widely used in the fields of biology, chemistry and materials. Recently, a few of terpyridine transition metal complexes with different biological and chemical activities were reported in the literature (Chen et al., 2013; Huang et al., 2013; Hussain et al., 2012; Maity et al., 2011; Roy et al., 2011; Field et al., 2007). However, studies concerning the third-order NLO properties of terpyridine transition metal complexes are limited. Based on the above considerations, we designed and synthesized a binuclear terpyridine Co^II complex bis­(µ-4,4'-oxydibenzoato)-κ³O,O':O;κ³O:\ O,O'-bis­[(4'-phenyl-2,2':6',2''-terpyridine-κ³N,\ N',N'')cobalt(II)], (1), with a 1:1 metal ion to ligand ratio by controlling the reaction conditions, and used the Z-scan technique to evaluate its NLO properties. Our results show that the nonlinear optical effect in (1) is much more pronounced than in PTP. We report here the crystal structure and third-order NLO properties of (1).

To prepare the thin films, a fine powder of the sample were dispersed in ethanol using ultrasonic processing. The mixture was then spin-coated (1000 r.p.m., 30 s) onto cleaned quartz glass substrates and dried at room temperature for 2 h. The thickness of the film was measured with a thickness gauge [about 2 µm for (1)]. The nonlinear optical refraction and absorption were obtained with a linearly polarized laser light (7 ns, 10 Hz, 532 nm) generated from a mode-locked Q-switched Nd:YAG laser. The spatial profiles of the optical pulses are nearly Gaussian after being passed through a filter. The incident and transmitted pulsed energies are measured simultaneously by two energy detectors (RJP-765 Energy probes, laser precision, Laserprobe Corp), which were linked to a computer through an RS232 inter­face. The sample was mounted on a translation stage that was controlled by the computer to move along the z axis with respect to the focal point. An aperture of 0.5 mm radius was placed in front of the transmission detector and the transmittance was recorded as a function of the sample position on the z axis (closed-aperture Z-scan). For measuring the NLO absorption, the Z-dependent sample transmittance was taken without the aperture (open-aperture Z-scan).

Complex (1) exhibits a discrete structure with the ratio of the PTP ligand and the Co^II ion being 1:1. Its asymmetric unit contains one Co^II cation, one PTP ligand and one ODA^2- dianion. As shown in Fig. 1, each Co^II atom is situated in a distorted o­cta­hedral coordination sphere, defined by three N atoms from one PPT ligand and by three O atoms from two different ODA^2- ligands. In this o­cta­hedral coordination sphere, atoms N1, N2, N3 and O3ⁱ [symmetry code: (i) -x+1, -y+1, -z] lie in the basal plane, while atoms O1 and O4ⁱ occupy the apical positions. The Co—N bond lengths (Table 2) are within the ranges reported for Co^II complexes (Zhang, Zhang et al., 2015). Of the Co—O bond lengths (Table 2), Co1—O4ⁱ is much longer than the others. The cis angles subtended at the Co^II atom by ligating atoms cover the range 58.69 (7)–110.16 (8)° (Table 2). Thus, the coordination geometry around the Co^II atom can be described as a distorted CoO₃N₃ o­cta­hedron. The PTP ligand chelates the Co^II atom and the ratio of metal ions and ligands is 1:1. Previous research showed that the ratio of metal ions and ligands plays an important role in the properties of the target compounds. For instance, Ma and coworker found that mononuclear terpyridine [Zn^II(PTP)]·X₂ (X = NO₃, CH₃COO, Cl and SO₄) complexes with a 1:1 ratio of metal ions and ligands exhibit promising in vitro tumour-inhibiting activities (Ma et al., 2010), which are higher than that of cisplatin against the following human tumor cell lines: promyelocyticfina leukaemia (HL-60), hepatocellula rcarcinoma (Bel-7402), gastric carcinoma (BGC-823) and nasopharyngeal carcinoma (KB). However, the mononuclear terpyridine [Zn^II(PTP)₂]·(NO₃)₂ complexes with a 1:2 ratio of metal ions and ligands do not bind DNA significantly (Sinha et al., 2015). They also reported four mononuclear terpyridine [Cu^II(PTP)]·X₂ (X = NO₃ and CH₃COO) complexes with a 1:1 ratio of metal ions and ligands which exhibit high catalytic activity, under mild conditions and in alkaline aqueous solution, for the aerobic oxidation of benzylic alcohols in combination with TEMPO (2,2,6,6-tetra­methyl­piperidinyl-1-oxyl radical) (Ma et al., 2014). Inter­estingly, the mononuclear terpyridine [Co^II(PTP)₂]·(NO₃)₂ complex with a 1:2 ratio of metal ions and ligands, can bind with the major groove of double helical DNA (Sinha et al., 2015).

In the title compound, (1), the ODA^2- ligand employs mono- and bidentate carboxyl­ate groups, adopting a µ₂-coordination mode, connecting two Co^II ions into a ring-like structure. The Co···Co separation within the ring is 11.76 (7) Å. There are two kinds of noncovalent inter­actions involved in the stabilization of the crystal lattice. In (1), the binuclear units are linked by a π–π inter­action of 3.57 (3) Å between the pyridine rings of the TPP ligands and a C—H··· π inter­action with distances of 3.74 (6) Å into a one-dimensional chain along the c axis. These one-dimensional chains are further connected by C—H··· π inter­actions, with distances of 3.68 (10) Å, into two-dimensional networks. Weak aromatic inter­actions have important effects on the properties and structures of compounds. Similar cases were encountered for comparable structures (Fu et al., 2015; McMurtrie & Dance, 2009). Field and co-workers (Field et al., 2012) found that [Pt(NCS)(PTP)]SbF₆ is porous, with empty channels stabilized by extended π–π inter­actions. When the compound was exposed to vapours of aceto­nitrile, the gaseous molecules were sorbed without loss of single crystallinity to give the adduct [Pt(NCS)(PTP)]SbF₆·CH₃CN. Similarly, this compound can sorb vapours of methanol and acetone without loss of single crystallinity to form [Pt(NCS)(PTP)]SbF₆·CH₃OH and [Pt(NCS)(PTP)]SbF₆·(CH₃)₂CO, respectively.

Although a few transition metal complexes and clusters with excellent third-order NLO properties have been reported, the data were obtained in solution (Zhang et al., 2007; Zhang, Liu & Lang, 2015). This is no suitable performance criterion for neat materials. In order to evaluate the third-order NLO performance of (1), films of (1) and TPP were prepared by spin coating and conducted open-aperture and closed-aperture Z-scan experiments. The open-aperture data of PTP and (1) are depicted in Figs. 3 and 4. It is obvious that PTP and (1) exhibit different third-order nonlinear optical absorption. From Fig. 3, the incident light irradiance is low in the far field, and the transmittance remains unchanged. As the sample moves towards the focal point, the incident light irradiance rises and the absorption increases. In the focus position, the absorption reaches the maximum. The open-aperture data clearly suggest the presence of reverse saturable absorption (RSA) behavior. The normalized transmittance drops to about 0.77. The corresponding third-order NLO absorptive coefficient β(MKS) is calculated to be 8.96 × 10 ^-7 m W^-1. It can be seen from Fig. 4 that the transmittance increases as the incident light irradiance rises. The normalized transmittance reaches the maximum at the focus position, which indicates that saturation absorption occurs. The β values is calculated to be -37.3 × 10 ^-7 m W^-1. The corresponding third-order NLO susceptibility χ⁽³⁾ are calculated as 6.01 × 10 ^-8 e.s.u. for (1) and 1.44 × 10 ^-8 e.s.u. for PTP. Our results show that the third-order NLO susceptibility χ⁽³⁾ of (1) is about four times that of PTP. This result is in agreement with the fact that the incorporation of transition metal atoms into π-conjugated organic systems may introduce more sublevels into the energy hierarchy, which is in favour of delocalization of the π-electron cloud. In addition, the charge-transfer nature of the metal–ligand bonds can also enhance the nonlinearity. The χ⁽³⁾ values of (1) and PTP in the solid state are much larger than those of other neat materials, such as neat inorganic semiconductors (about 10 ^-10 e.s.u.) and conjugated polymers (Chen et al., 2014; Liu et al., 2013).

Synthesis and crystallization

Co(CH₃COO)₂ (0.1 mmol, 0.018 g), 4,4'-oxybis(benzoic acid) (H₂ODA; 0.1 mmol, 0.026 g) and PTP (0.2 mmol, 0.031 g) were added to a mixture of distilled water (5 ml) and ethanol (5 ml), and the pH was adjusted to 5.0 by the addition of 0.2 M NaOH. The resulting mixture was stirred for 1 h, transferred into a Parr Teflon-lined stainless steel vessel, and then sealed and heated at 423 K for 3 d, followed by rapid cooling to ambient temperature. Red block-shaped crystals were collected manually, washed with distilled water and dried in air at ambient temperature (yield 86%, based on Co). Elemental analysis calculated for C₇₀H₄₆Co₂N₆O₁₀: C 67.31, N 6.73, H 3.71%; found: C 67.28, N 6.75, H, 3.73%.

Refinement details

Crystal data, data collection and structure refinement details are summarized in Table 1. C-bound H atoms were fixed geometrically and allowed to ride on their parent atom, with C—H = 0.93 Å and U_iso(H) = 1.2U_eq(C).

Computing details

Data collection: Please supply data collection software; cell refinement: SAINT-Plus (Bruker, 2012); data reduction: SAINT-Plus (Bruker, 2012); program(s) used to solve structure: SHELXT (Sheldrick, 2015a); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015b); molecular graphics: OLEX2 (Dolomanov et al., 2009); software used to prepare material for publication: OLEX2 (Dolomanov et al., 2009).

Figures

	Fig. 1. The coordination environment of the Co^II centre in (1), showing the atom-labelling scheme and 50% probability displacement ellipsoids. [Symmetry code: (i) -x+1, -y+1, -z.]
	Fig. 2. The packing structure of (1) along the c axis. H atoms have been omitted for clarity.
	Fig. 3. The NLO absorption data of PTP. The data were obtained under an open-aperture configuration.
	Fig. 4. The NLO absorption data of (1). The data were obtained under an open-aperture configuration.

Bis(µ-4,4'-oxydibenzoato)-κ³O,O':O'';κ³O'':O,O'-bis[(4'-phenyl-2,2':6',2''-terpyridine-κ³N,N',N'')cobalt(II)]

Crystal data

[Co2(C14H8O5)2(C21H15N3)2]	Z = 1
Mr = 1248.99	F(000) = 642
Triclinic, P1	Dx = 1.456 Mg m^−3
a = 9.710 (9) Å	Mo Kα radiation, λ = 0.71073 Å
b = 10.891 (12) Å	Cell parameters from 3954 reflections
c = 15.546 (16) Å	θ = 2.3–28.2°
α = 77.129 (15)°	µ = 0.65 mm^−1
β = 74.474 (15)°	T = 296 K
γ = 65.034 (15)°	Block, red
V = 1425 (3) Å^3	0.29 × 0.26 × 0.22 mm

Data collection

Bruker SMART CCD 6000 area-detector diffractometer	5301 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.016
phi and ω scans	θmax = 28.5°, θmin = 2.1°
Absorption correction: multi-scan (SADABS; Bruker, 2007)	h = −6→12
Tmin = 0.66, Tmax = 0.71	k = −8→14
8920 measured reflections	l = −20→19
6574 independent reflections

Refinement

Refinement on F^2	0 restraints
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) = 0.121	w = 1/[σ^2(Fo^2) + (0.063P)^2 + 0.254P] where P = (Fo^2 + 2Fc^2)/3
S = 1.09	(Δ/σ)max = 0.001
6574 reflections	Δρmax = 0.37 e Å^−3
397 parameters	Δρmin = −0.51 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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
Co1	0.26720 (3)	0.74565 (3)	0.33762 (2)	0.03165 (10)
O1	0.27408 (16)	0.93005 (16)	0.28187 (10)	0.0377 (4)
O2	0.44156 (19)	1.0023 (2)	0.30945 (12)	0.0567 (5)
O3	0.7626 (2)	0.3079 (2)	−0.22612 (12)	0.0531 (5)
O4	0.7361 (2)	0.4721 (2)	−0.33961 (12)	0.0576 (5)
O5	0.8489 (2)	0.7387 (2)	−0.04874 (14)	0.0700 (7)
N1	0.01997 (19)	0.81678 (18)	0.39856 (12)	0.0325 (4)
N2	0.26266 (18)	0.74909 (17)	0.47066 (11)	0.0293 (4)
N3	0.51276 (19)	0.64794 (18)	0.34928 (12)	0.0348 (4)
C1	−0.0988 (2)	0.8430 (2)	0.35879 (16)	0.0389 (5)
H1	−0.0769	0.8285	0.2990	0.047*
C2	−0.2540 (3)	0.8912 (3)	0.40368 (17)	0.0440 (6)
H2	−0.3334	0.9087	0.3743	0.053*
C3	−0.2864 (2)	0.9121 (3)	0.49273 (16)	0.0453 (6)
H3	−0.3884	0.9436	0.5241	0.054*
C4	−0.1651 (2)	0.8856 (2)	0.53529 (15)	0.0381 (5)
H4	−0.1850	0.8994	0.5951	0.046*
C5	−0.0133 (2)	0.8382 (2)	0.48621 (13)	0.0291 (4)
C6	0.1242 (2)	0.8022 (2)	0.52688 (14)	0.0290 (4)
C7	0.1150 (2)	0.8182 (2)	0.61441 (14)	0.0330 (4)
H7	0.0188	0.8571	0.6510	0.040*
C8	0.2515 (2)	0.7753 (2)	0.64794 (14)	0.0331 (4)
C9	0.3948 (2)	0.7180 (2)	0.58839 (14)	0.0355 (5)
H9	0.4875	0.6886	0.6080	0.043*
C10	0.3968 (2)	0.7057 (2)	0.50062 (14)	0.0304 (4)
C11	0.5394 (2)	0.6459 (2)	0.43115 (14)	0.0313 (4)
C12	0.6901 (2)	0.5886 (2)	0.44862 (16)	0.0394 (5)
H12	0.7064	0.5855	0.5055	0.047*
C13	0.8155 (3)	0.5363 (3)	0.37925 (18)	0.0471 (6)
H13	0.9162	0.5002	0.3892	0.056*
C14	0.7888 (3)	0.5385 (3)	0.29572 (17)	0.0458 (6)
H14	0.8706	0.5032	0.2490	0.055*
C15	0.6359 (3)	0.5952 (2)	0.28345 (16)	0.0434 (6)
H15	0.6177	0.5968	0.2274	0.052*
C16	0.2426 (3)	0.7886 (2)	0.74323 (15)	0.0363 (5)
C17	0.1072 (3)	0.8785 (3)	0.79329 (16)	0.0452 (6)
H17	0.0213	0.9301	0.7669	0.054*
C18	0.1010 (3)	0.8907 (3)	0.88128 (17)	0.0528 (6)
H18	0.0112	0.9505	0.9133	0.063*
C19	0.2281 (4)	0.8141 (3)	0.92209 (18)	0.0564 (7)
H19	0.2243	0.8234	0.9808	0.068*
C20	0.3594 (4)	0.7244 (3)	0.87454 (19)	0.0652 (8)
H20	0.4440	0.6718	0.9019	0.078*
C21	0.3675 (3)	0.7114 (3)	0.78584 (18)	0.0564 (7)
H21	0.4574	0.6503	0.7548	0.068*
C22	0.5145 (2)	0.9015 (2)	0.17516 (14)	0.0343 (5)
C23	0.4721 (3)	0.8549 (3)	0.11340 (16)	0.0428 (5)
H23	0.3714	0.8596	0.1228	0.051*
C24	0.5800 (3)	0.8013 (3)	0.03750 (17)	0.0513 (6)
H24	0.5507	0.7718	−0.0038	0.062*
C25	0.7320 (3)	0.7924 (3)	0.02405 (16)	0.0450 (6)
C26	0.7752 (3)	0.8412 (3)	0.08355 (17)	0.0463 (6)
H26	0.8759	0.8367	0.0738	0.056*
C27	0.6664 (3)	0.8969 (3)	0.15795 (15)	0.0407 (5)
H27	0.6946	0.9316	0.1970	0.049*
C28	0.8244 (3)	0.6613 (3)	−0.09975 (17)	0.0498 (6)
C29	0.8011 (3)	0.7170 (3)	−0.18676 (18)	0.0460 (6)
H29	0.7989	0.8042	−0.2095	0.055*
C30	0.7812 (3)	0.6394 (2)	−0.23930 (16)	0.0417 (5)
H30	0.7645	0.6758	−0.2974	0.050*
C31	0.7859 (2)	0.5096 (2)	−0.20621 (14)	0.0353 (5)
C32	0.8131 (3)	0.4549 (3)	−0.11914 (17)	0.0512 (6)
H32	0.8190	0.3666	−0.0968	0.061*
C33	0.8315 (4)	0.5314 (3)	−0.06599 (18)	0.0611 (8)
H33	0.8485	0.4951	−0.0079	0.073*
C34	0.4041 (2)	0.9490 (2)	0.26201 (15)	0.0351 (5)
C35	0.7602 (2)	0.4256 (3)	−0.26118 (16)	0.0402 (5)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Co1	0.02599 (15)	0.03727 (18)	0.02785 (16)	−0.00585 (12)	−0.00477 (10)	−0.01023 (12)
O1	0.0292 (7)	0.0391 (8)	0.0395 (9)	−0.0098 (6)	−0.0040 (6)	−0.0049 (7)
O2	0.0376 (9)	0.0928 (15)	0.0475 (10)	−0.0237 (9)	−0.0001 (7)	−0.0367 (10)
O3	0.0646 (12)	0.0598 (11)	0.0451 (10)	−0.0327 (10)	−0.0016 (8)	−0.0200 (9)
O4	0.0627 (12)	0.0597 (12)	0.0482 (11)	−0.0068 (9)	−0.0259 (9)	−0.0187 (9)
O5	0.0627 (12)	0.1126 (18)	0.0617 (13)	−0.0595 (13)	0.0269 (10)	−0.0583 (13)
N1	0.0262 (8)	0.0385 (10)	0.0313 (9)	−0.0075 (7)	−0.0064 (7)	−0.0110 (8)
N2	0.0217 (8)	0.0316 (9)	0.0307 (9)	−0.0040 (7)	−0.0059 (6)	−0.0078 (7)
N3	0.0278 (9)	0.0351 (10)	0.0341 (10)	−0.0036 (7)	−0.0051 (7)	−0.0091 (8)
C1	0.0316 (11)	0.0482 (13)	0.0361 (12)	−0.0097 (10)	−0.0106 (9)	−0.0109 (10)
C2	0.0273 (10)	0.0563 (15)	0.0485 (14)	−0.0104 (10)	−0.0147 (9)	−0.0096 (11)
C3	0.0226 (10)	0.0616 (16)	0.0440 (14)	−0.0072 (10)	−0.0047 (9)	−0.0125 (12)
C4	0.0235 (10)	0.0504 (13)	0.0336 (11)	−0.0058 (9)	−0.0051 (8)	−0.0101 (10)
C5	0.0229 (9)	0.0315 (10)	0.0293 (10)	−0.0056 (8)	−0.0052 (7)	−0.0067 (8)
C6	0.0232 (9)	0.0305 (10)	0.0297 (10)	−0.0058 (8)	−0.0052 (7)	−0.0059 (8)
C7	0.0250 (9)	0.0396 (11)	0.0300 (11)	−0.0072 (8)	−0.0024 (8)	−0.0100 (9)
C8	0.0317 (10)	0.0367 (11)	0.0300 (11)	−0.0101 (9)	−0.0081 (8)	−0.0065 (9)
C9	0.0272 (10)	0.0442 (12)	0.0336 (11)	−0.0091 (9)	−0.0088 (8)	−0.0080 (9)
C10	0.0237 (9)	0.0318 (10)	0.0324 (11)	−0.0061 (8)	−0.0059 (8)	−0.0067 (8)
C11	0.0232 (9)	0.0318 (10)	0.0337 (11)	−0.0056 (8)	−0.0044 (8)	−0.0054 (9)
C12	0.0258 (10)	0.0452 (13)	0.0423 (13)	−0.0075 (9)	−0.0087 (9)	−0.0061 (10)
C13	0.0246 (10)	0.0481 (14)	0.0569 (16)	−0.0046 (10)	−0.0049 (10)	−0.0071 (12)
C14	0.0306 (11)	0.0432 (13)	0.0458 (14)	−0.0022 (10)	0.0037 (9)	−0.0095 (11)
C15	0.0344 (11)	0.0455 (13)	0.0347 (12)	−0.0017 (10)	−0.0006 (9)	−0.0100 (10)
C16	0.0387 (11)	0.0427 (12)	0.0305 (11)	−0.0170 (10)	−0.0066 (9)	−0.0082 (9)
C17	0.0402 (12)	0.0606 (16)	0.0367 (13)	−0.0206 (11)	−0.0030 (10)	−0.0128 (11)
C18	0.0547 (15)	0.0714 (18)	0.0363 (13)	−0.0298 (14)	0.0047 (11)	−0.0202 (13)
C19	0.0751 (19)	0.0717 (19)	0.0328 (13)	−0.0365 (16)	−0.0112 (12)	−0.0092 (13)
C20	0.0631 (18)	0.086 (2)	0.0454 (16)	−0.0162 (16)	−0.0271 (14)	−0.0119 (15)
C21	0.0445 (14)	0.0736 (19)	0.0435 (15)	−0.0054 (13)	−0.0165 (11)	−0.0189 (13)
C22	0.0322 (10)	0.0382 (12)	0.0311 (11)	−0.0114 (9)	−0.0055 (8)	−0.0069 (9)
C23	0.0362 (11)	0.0600 (15)	0.0385 (13)	−0.0230 (11)	−0.0042 (9)	−0.0130 (11)
C24	0.0534 (15)	0.0784 (19)	0.0393 (13)	−0.0386 (14)	−0.0008 (11)	−0.0241 (13)
C25	0.0471 (13)	0.0586 (15)	0.0371 (13)	−0.0292 (12)	0.0074 (10)	−0.0222 (11)
C26	0.0373 (12)	0.0665 (16)	0.0451 (14)	−0.0288 (12)	0.0035 (10)	−0.0224 (12)
C27	0.0384 (12)	0.0580 (15)	0.0345 (12)	−0.0244 (11)	−0.0030 (9)	−0.0156 (11)
C28	0.0449 (13)	0.0741 (18)	0.0414 (14)	−0.0319 (13)	0.0098 (10)	−0.0323 (13)
C29	0.0399 (12)	0.0403 (13)	0.0551 (15)	−0.0137 (10)	−0.0018 (11)	−0.0137 (11)
C30	0.0380 (12)	0.0437 (13)	0.0378 (13)	−0.0092 (10)	−0.0073 (9)	−0.0078 (10)
C31	0.0302 (10)	0.0410 (12)	0.0317 (11)	−0.0081 (9)	−0.0034 (8)	−0.0137 (9)
C32	0.0710 (18)	0.0534 (15)	0.0391 (14)	−0.0334 (14)	−0.0134 (12)	−0.0026 (12)
C33	0.089 (2)	0.083 (2)	0.0306 (13)	−0.0519 (18)	−0.0132 (13)	−0.0051 (13)
C34	0.0300 (10)	0.0383 (11)	0.0320 (11)	−0.0064 (9)	−0.0066 (8)	−0.0081 (9)
C35	0.0282 (10)	0.0496 (14)	0.0403 (13)	−0.0078 (9)	−0.0035 (9)	−0.0194 (11)

Geometric parameters (Å, º)

Co1—O1	2.024 (3)	C12—C13	1.398 (3)
Co1—O3^i	2.071 (2)	C13—H13	0.9300
Co1—O4^i	2.379 (3)	C13—C14	1.384 (4)
Co1—N1	2.191 (3)	C14—H14	0.9300
Co1—N2	2.065 (3)	C14—C15	1.395 (4)
Co1—N3	2.203 (3)	C15—H15	0.9300
O1—C34	1.309 (3)	C16—C17	1.414 (3)
O2—C34	1.235 (3)	C16—C21	1.392 (3)
O3—Co1^i	2.071 (2)	C17—H17	0.9300
O3—C35	1.270 (3)	C17—C18	1.386 (4)
O4—Co1^i	2.379 (3)	C18—H18	0.9300
O4—C35	1.255 (3)	C18—C19	1.391 (4)
O5—C25	1.399 (3)	C19—H19	0.9300
O5—C28	1.401 (3)	C19—C20	1.376 (4)
N1—C1	1.349 (3)	C20—H20	0.9300
N1—C5	1.363 (3)	C20—C21	1.396 (4)
N2—C6	1.359 (3)	C21—H21	0.9300
N2—C10	1.358 (3)	C22—C23	1.397 (3)
N3—C11	1.359 (3)	C22—C27	1.408 (3)
N3—C15	1.354 (3)	C22—C34	1.519 (3)
C1—H1	0.9300	C23—H23	0.9300
C1—C2	1.402 (3)	C23—C24	1.400 (3)
C2—H2	0.9300	C24—H24	0.9300
C2—C3	1.383 (4)	C24—C25	1.398 (4)
C3—H3	0.9300	C25—C26	1.389 (3)
C3—C4	1.398 (3)	C26—H26	0.9300
C4—H4	0.9300	C26—C27	1.392 (3)
C4—C5	1.397 (3)	C27—H27	0.9300
C5—C6	1.495 (3)	C28—C29	1.389 (4)
C6—C7	1.385 (3)	C28—C33	1.374 (4)
C7—H7	0.9300	C29—H29	0.9300
C7—C8	1.409 (3)	C29—C30	1.396 (4)
C8—C9	1.421 (3)	C30—H30	0.9300
C8—C16	1.497 (3)	C30—C31	1.378 (4)
C9—H9	0.9300	C31—C32	1.399 (4)
C9—C10	1.394 (3)	C31—C35	1.511 (3)
C10—C11	1.503 (3)	C32—H32	0.9300
C11—C12	1.404 (3)	C32—C33	1.386 (4)
C12—H12	0.9300	C33—H33	0.9300
O1—Co1—O3^i	97.90 (9)	C13—C14—H14	120.9
O1—Co1—O4^i	156.25 (7)	C13—C14—C15	118.3 (2)
O1—Co1—N1	97.66 (7)	C15—C14—H14	120.9
O1—Co1—N2	100.92 (8)	N3—C15—C14	123.2 (2)
O1—Co1—N3	95.24 (7)	N3—C15—H15	118.4
O3^i—Co1—O4^i	58.69 (7)	C14—C15—H15	118.4
O3^i—Co1—N1	93.61 (9)	C17—C16—C8	121.3 (2)
O3^i—Co1—N3	110.16 (8)	C21—C16—C8	120.9 (2)
N1—Co1—O4^i	88.47 (8)	C21—C16—C17	117.8 (2)
N1—Co1—N3	151.05 (8)	C16—C17—H17	119.6
N2—Co1—O3^i	159.67 (8)	C18—C17—C16	120.7 (2)
N2—Co1—O4^i	102.83 (7)	C18—C17—H17	119.6
N2—Co1—N1	76.37 (7)	C17—C18—H18	119.7
N2—Co1—N3	75.80 (7)	C17—C18—C19	120.6 (3)
N3—Co1—O4^i	90.06 (8)	C19—C18—H18	119.7
C34—O1—Co1	121.01 (13)	C18—C19—H19	120.4
C35—O3—Co1^i	96.97 (16)	C20—C19—C18	119.2 (3)
C35—O4—Co1^i	83.32 (16)	C20—C19—H19	120.4
C25—O5—C28	118.1 (2)	C19—C20—H20	119.5
C1—N1—Co1	127.44 (16)	C19—C20—C21	120.9 (3)
C1—N1—C5	118.18 (18)	C21—C20—H20	119.5
C5—N1—Co1	114.37 (13)	C16—C21—C20	120.8 (3)
C6—N2—Co1	119.35 (14)	C16—C21—H21	119.6
C10—N2—Co1	120.40 (14)	C20—C21—H21	119.6
C10—N2—C6	120.14 (19)	C23—C22—C27	118.6 (2)
C11—N3—Co1	114.78 (13)	C23—C22—C34	121.7 (2)
C15—N3—Co1	126.77 (16)	C27—C22—C34	119.69 (19)
C15—N3—C11	118.42 (19)	C22—C23—H23	119.7
N1—C1—H1	118.6	C22—C23—C24	120.5 (2)
N1—C1—C2	122.8 (2)	C24—C23—H23	119.7
C2—C1—H1	118.6	C23—C24—H24	120.1
C1—C2—H2	120.8	C25—C24—C23	119.7 (2)
C3—C2—C1	118.5 (2)	C25—C24—H24	120.1
C3—C2—H2	120.8	C24—C25—O5	124.2 (2)
C2—C3—H3	120.2	C26—C25—O5	115.3 (2)
C2—C3—C4	119.6 (2)	C26—C25—C24	120.5 (2)
C4—C3—H3	120.2	C25—C26—H26	120.3
C3—C4—H4	120.7	C25—C26—C27	119.4 (2)
C5—C4—C3	118.7 (2)	C27—C26—H26	120.3
C5—C4—H4	120.7	C22—C27—H27	119.4
N1—C5—C4	122.17 (18)	C26—C27—C22	121.2 (2)
N1—C5—C6	115.27 (17)	C26—C27—H27	119.4
C4—C5—C6	122.5 (2)	C29—C28—O5	118.1 (3)
N2—C6—C5	114.14 (19)	C33—C28—O5	120.6 (3)
N2—C6—C7	121.67 (18)	C33—C28—C29	121.2 (2)
C7—C6—C5	124.18 (18)	C28—C29—H29	120.6
C6—C7—H7	120.0	C28—C29—C30	118.7 (2)
C6—C7—C8	119.94 (19)	C30—C29—H29	120.6
C8—C7—H7	120.0	C29—C30—H30	119.5
C7—C8—C9	117.4 (2)	C31—C30—C29	120.9 (2)
C7—C8—C16	120.34 (19)	C31—C30—H30	119.5
C9—C8—C16	122.30 (19)	C30—C31—C32	119.2 (2)
C8—C9—H9	119.9	C30—C31—C35	121.6 (2)
C10—C9—C8	120.12 (19)	C32—C31—C35	119.2 (2)
C10—C9—H9	119.9	C31—C32—H32	119.8
N2—C10—C9	120.74 (18)	C33—C32—C31	120.4 (3)
N2—C10—C11	113.56 (19)	C33—C32—H32	119.8
C9—C10—C11	125.69 (18)	C28—C33—C32	119.5 (3)
N3—C11—C10	115.17 (18)	C28—C33—H33	120.2
N3—C11—C12	121.44 (19)	C32—C33—H33	120.2
C12—C11—C10	123.4 (2)	O1—C34—C22	117.22 (19)
C11—C12—H12	120.5	O2—C34—O1	124.0 (2)
C13—C12—C11	119.0 (2)	O2—C34—C22	118.7 (2)
C13—C12—H12	120.5	O3—C35—C31	118.6 (2)
C12—C13—H13	120.2	O4—C35—O3	120.9 (2)
C14—C13—C12	119.6 (2)	O4—C35—C31	120.4 (2)
C14—C13—H13	120.2
Co1—O1—C34—O2	−99.8 (2)	C9—C8—C16—C21	−19.1 (4)
Co1—O1—C34—C22	80.1 (2)	C9—C10—C11—N3	−178.4 (2)
Co1^i—O3—C35—O4	3.3 (2)	C9—C10—C11—C12	3.0 (4)
Co1^i—O3—C35—C31	−177.15 (16)	C10—N2—C6—C5	−176.69 (18)
Co1^i—O4—C35—O3	−2.8 (2)	C10—N2—C6—C7	2.2 (3)
Co1^i—O4—C35—C31	177.59 (19)	C10—C11—C12—C13	−179.6 (2)
Co1—N1—C1—C2	−178.59 (18)	C11—N3—C15—C14	0.2 (4)
Co1—N1—C5—C4	178.96 (17)	C11—C12—C13—C14	−1.7 (4)
Co1—N1—C5—C6	−3.2 (2)	C12—C13—C14—C15	0.8 (4)
Co1—N2—C6—C5	7.0 (2)	C13—C14—C15—N3	0.0 (4)
Co1—N2—C6—C7	−174.16 (16)	C15—N3—C11—C10	−179.7 (2)
Co1—N2—C10—C9	174.78 (16)	C15—N3—C11—C12	−1.2 (3)
Co1—N2—C10—C11	−5.4 (2)	C16—C8—C9—C10	179.0 (2)
Co1—N3—C11—C10	2.2 (2)	C16—C17—C18—C19	−0.2 (4)
Co1—N3—C11—C12	−179.22 (17)	C17—C16—C21—C20	−1.1 (4)
Co1—N3—C15—C14	177.98 (19)	C17—C18—C19—C20	−1.0 (5)
O5—C25—C26—C27	179.9 (2)	C18—C19—C20—C21	1.2 (5)
O5—C28—C29—C30	178.1 (2)	C19—C20—C21—C16	−0.1 (5)
O5—C28—C33—C32	−177.4 (3)	C21—C16—C17—C18	1.2 (4)
N1—C1—C2—C3	−0.3 (4)	C22—C23—C24—C25	0.9 (4)
N1—C5—C6—N2	−2.1 (3)	C23—C22—C27—C26	−3.1 (4)
N1—C5—C6—C7	179.1 (2)	C23—C22—C34—O1	7.7 (3)
N2—C6—C7—C8	−1.8 (3)	C23—C22—C34—O2	−172.5 (2)
N2—C10—C11—N3	1.8 (3)	C23—C24—C25—O5	179.0 (3)
N2—C10—C11—C12	−176.8 (2)	C23—C24—C25—C26	−2.5 (4)
N3—C11—C12—C13	1.9 (3)	C24—C25—C26—C27	1.2 (4)
C1—N1—C5—C4	0.1 (3)	C25—O5—C28—C29	109.9 (3)
C1—N1—C5—C6	177.90 (19)	C25—O5—C28—C33	−73.4 (4)
C1—C2—C3—C4	0.3 (4)	C25—C26—C27—C22	1.6 (4)
C2—C3—C4—C5	−0.1 (4)	C27—C22—C23—C24	1.8 (4)
C3—C4—C5—N1	−0.1 (3)	C27—C22—C34—O1	−168.9 (2)
C3—C4—C5—C6	−177.7 (2)	C27—C22—C34—O2	10.9 (3)
C4—C5—C6—N2	175.7 (2)	C28—O5—C25—C24	−15.2 (4)
C4—C5—C6—C7	−3.1 (3)	C28—O5—C25—C26	166.2 (3)
C5—N1—C1—C2	0.1 (3)	C28—C29—C30—C31	−0.6 (3)
C5—C6—C7—C8	177.0 (2)	C29—C28—C33—C32	−0.8 (4)
C6—N2—C10—C9	−1.5 (3)	C29—C30—C31—C32	−0.8 (3)
C6—N2—C10—C11	178.28 (18)	C29—C30—C31—C35	178.3 (2)
C6—C7—C8—C9	0.7 (3)	C30—C31—C32—C33	1.5 (4)
C6—C7—C8—C16	−178.4 (2)	C30—C31—C35—O3	−178.4 (2)
C7—C8—C9—C10	−0.1 (3)	C30—C31—C35—O4	1.1 (3)
C7—C8—C16—C17	−19.3 (3)	C31—C32—C33—C28	−0.7 (4)
C7—C8—C16—C21	159.9 (2)	C32—C31—C35—O3	0.7 (3)
C8—C9—C10—N2	0.5 (3)	C32—C31—C35—O4	−179.7 (2)
C8—C9—C10—C11	−179.3 (2)	C33—C28—C29—C30	1.5 (4)
C8—C16—C17—C18	−179.5 (2)	C34—C22—C23—C24	−174.8 (2)
C8—C16—C21—C20	179.7 (3)	C34—C22—C27—C26	173.5 (2)
C9—C8—C16—C17	161.7 (2)	C35—C31—C32—C33	−177.7 (2)

Symmetry code: (i) −x+1, −y+1, −z.