Magnetic properties of a mononuclear iron(II) complex with a typical FeN₆ coordination octa­hedron

A mononuclear iron(II) complex with the tripodal ligand bis­(pyridin-2-yl­methyl)­(quinolin-2-yl­methyl)­amine (dpqa) has been synthesized and structurally characterized, namely [bis­(pyridin-2-yl­methyl)­(quinolin-2-yl­methyl)­amine-[kappa]⁴N,N',N'',N''']bis­(thio­cyanato-[kappa]S)iron(II), [Fe(NCS)₂(C₂₂H₂₀N₄)], exhibits a three-dimensional supra­molecular network via [pi]-[pi] inter­actions and S...H-C hydrogen-bonding inter­actions between adjacent Fe^II centres. Temperature-dependent mag­netic measurements under different external pressures and X-ray diffraction measurements indicate that all the Fe^II centres in this complex retain a high-spin state upon cooling from 300 to 2 K. The surprising absence of spin-crossover behaviour for this mononuclear iron(II) complex is attributed to the steric hindrance originating from the substituted quinoline ring in the dpqa ligand.

S1. Comment

Many studies have been carried out on Fe^II compounds with the typical form of an FeN₆ coordination octahedron, which might present fascinating spin-crossover (SCO) properties and specific lattice interactions (Thompson et al., 2004; Yu & Li, 2011; Halcrow, 2011; Bousseksou et al., 2011). Among these efforts, the various noncovalent interactions between different Fe^II units in the solid state have also been verified as an efficient method for achieving an abrupt spin transition with significant bistability, for example by changing crystallization counteranions or solvents (Halder et al., 2002; Sunatsuki et al., 2003). Recently, the effect of noncovalent interactions, including hydrogen bonding and π–π interactions, on SCO behaviour in two mononuclear Fe systems containing the tripodal ligand tris(pyridin-2-ylmethyl)amine (tpa; see scheme) has been reported (Li et al., 2010). This ligand possesses many advantages as a terminal ligand coordinated to metal atoms, namely its stability, strong coordination ability and multiple opportunities for π–π interactions. Considering the important role of π–π interactions in affecting SCO behaviour, and in order to investigate systematically the relationship between SCO behaviour and noncovalent (π–π) interactions, the new tripodal ligand bis(pyridin-2-ylmethyl)(quinolin-2-ylmethyl)amine (dpqa), which possesses the possibility of stronger π–π interactions, has been introduced to construct new mononuclear iron(II) compounds with the typical FeN₆ coordination octahedron (Li, Tao et al., 2008; Li, Yang et al., 2008). Herein, a new mononuclear iron(II) complex using this ligand, [Fe(NCS)₂(dpqa)], (I), has been synthesized and structurally characterized. In this structure, a rigid FeN₆ coordination octahedron for the Fe^II atom and much stronger π–π interactions are exhibited.

Compound (I) crystallizes in the monoclinic space group P2₁/c. Its asymmetric unit contains one complete C₁-symmetric [Fe(NCS)₂(dpqa)] molecule, as shown in Figs. 1 and 2. The neutral unit contains a tetradentate tripodal dpqa ligand, one Fe^II cation and two NCS^- anions, where only a cis configuration of the NCS^- groups is stable due to the geometric constraints of the tripodal ligand. The Fe^II centre is coordinated by six N atoms, four from the dpqa ligand and two from the NCS^- groups. The equatorial plane of the coordination octahedron of the Fe^II cation is formed by two NCS^- groups (N5 and N6), one pyridine N atom (N2) and aliphatic atom N4, while the axial positions are occupied by the pyridine ring associated with atom N1 and by the quinoline ring, with a dihedral angle of 16.19 (1)°. The average Fe—N bond length is 2.167 (3) Å, with a range of 2.050 (3)–2.273 (2) Å, corresponding to typical HS-Fe^II—N bond lengths (HS is high spin; [Reference for typical values?]). Here, the slightly longer Fe—N bond lengths [Fe—N3 = 2.273 (2) Å and Fe—N4 = 2.238 (2) Å] in the HS-Fe^II state are mostly caused by the steric strain originating from the substituted quinoline ring (Matouzenko et al., 1997); much shorter Fe—N_NCS bonds have also been observed in other SCO compounds containing Fe—N_NCS [Reference?]. At low temperature, the Σ parameter (Guionneau et al., 2001), which is used to quantify angular deviation from an ideal FeN₆ coordination octahedron, is 84.7° for (I), implying high-spin states. The adjacent neutral units are further interconnected by strong π_benzene–π_benzene [3.806 (1) Å] interactions and intricate S···H—C interactions [S2···H2—C2 = 2.948 (2) Å and S2···H22—C22 = 2.898 (2) Å] to form the three-dimensional supramolecular structure, shown in Figs. 2 and 3. However, no S···S interactions are observed. Thermal stability and powder X-ray diffraction experiments were also carried out to validate the structure of the (I), shown in Figs. 5 and 6, respectively.

The magnetic properties of (I) were studied in the temperature range 2–300 K using a SQUID magnetometer, and a plot of χ_MT versus T under ambient air pressure is shown in Fig. 4. At 300 K, the χ_MT value for (I) is 3.35 cm³ mol^-1 K, showing the HS state of the Fe^II cations. On cooling, the χ_MT values remain nearly constant down to 70 K. Below this temperature, χ_MT begins to decrease slowly and finally attains a value of 2.63 cm³ mol^-1 K at 2 K. Thus, the temperature-dependent decrease of χ_MT in the low-temperature region indicates the presence of zero-field splitting of the HS-Fe^II ground state (Garcia et al., 2005). The variable-temperature magnetic properties of (I) thus indicate that there is no SCO behaviour observable in the temperature range 2–300 K. [Rephrasing OK?]

It is well known that the application of hydrostatic pressure can be an approach that effectively triggers and/or modifies the behaviour of SCO compounds. Therefore, the magnetic properties of (I) under hydrostatic pressure up to 10 kbar (1 bar = 100 000 Pa) were also investigated in the temperature range 2–300 K in order to observe a possible pressure-induced spin transition of the HS-Fe^II state, but still no noticeable change was observed. All of the Fe^II cations remain in the HS state throughout the observed temperature range.

Compared with the crystal structure and spin transition behaviour of [Fe(NCS)₂(tpa)] (Li et al., 2010), in (I) the tripodal dpqa ligand plays a vital role in affecting a change in the HS state. In other mononuclear iron compounds, such as [Fe(NCS)₂(tpa)], the Fe—N(aliphatic) bond is usually longer than the Fe—N(pyridine) distances. However, in (I) the Fe—N(quinoline) bond is longer than the others, which might be caused by steric repulsion between the thiocyanate ligand and atom H14 of the quinoline ring. Thus, a long Fe—N bond would stablize the HS iron state, but not the low-spin states that exhibit shorter Fe—N bond lenghths. Therefore, the arm of the substituted quinoline ring not only facilitates the formation of π–π interactions but also tends to decrease the ligand field and elongate the Fe—N bond due to the supervenient steric hindrance. As a result, the rigid FeN₆ octahedron of the Fe^II cations and the dense structure type of (I) are stabilized over the complete temperature range, which could well explain the absence of a spin transition of the HS-Fe^II state either under hydrostatic pressure or thermal changes.

In summary, we have synthesized a new compound, (I), and structurally characterized it by X-ray crystallography. The crystal structure of (I) is stabilized by π–π supramolecular interactions and thus favours a highly co-operative SCO behaviour. No change in the spin state of (I) could be observed. Even the typical FeN₆ coordination octahedron necessary for SCO behaviour is present, and it is not affected by any kind of external perturbation (temperature or pressure). The steric hindrance originating from the substituted quinolinate ring of dpqa and the supervenient stiffness of the FeN₆ octahedron, compared with the corresponding observations in tpa, must play an important role in elongating the Fe—N bonds, decreasing the intensity of the ligand field and stabilizing the HS state of the Fe^II cations under any external stimulus. [Rephrasing OK?]

Related literature

For related literature, see: Bousseksou et al. (2011); Garcia et al. (2005); Guionneau et al. (2001); Halcrow (2011); Halder et al. (2002); Li et al. (2010); Li, Tao, Sun, Sato, Huang & Zheng (2008); Li, Yang, Tao, Sato, Huang & Zheng (2008); Matouzenko et al. (1997); Sunatsuki et al. (2003); Thompson et al. (2004); Yu & Li (2011).

S2. Experimental

The synthesis of dpqa was carried out according to the literature method of Li and co-workers (Li, Tao et al., 2008; Li, Yang et al., 2008). For the synthesis of the mononuclear complex, FeSO₄.7H₂O (0.1 mmol) and KSCN (0.2 mmol) were dissolved in methanol (5 ml), then ascorbic acid (5 mg) was added to the solution to avoid oxidation of the Fe^II ion. The solution was filtered to remove the K₂SO₄ precipitate, and an ethanol solution (10 ml) containing dpqa (0.1 mmol) and ascorbic acid (5 mg) was added to the filtrate immediately with stirring under a nitrogen atmosphere. The product precipitated as a powder, which was filtered off. The powder (30 mg) was dissolved in dimethylformamide (1 ml) and the solution was layered with ethanol to give yellow block-like single crystals of (I) in 40% yield. Elemental analysis, calculated: H 3.93, C 56.25, N 16.40%; experimental: H 4.12, C 55.91, N 16.94%.

Magnetic susceptibility measurements were carried out at a sweeping rate of 1 K min^-1 in the temperature range 2–300 K with a magnetic field of 5000 Oe on a Quantum Design MPMS XL-7 magnetometer. Magnetic measurements under pressure were performed using an EasyLab Mcell 10 hydrostatic pressure cell, which is specially designed for the MPMS set up; it is made of hardened beryllium bronze with silicon oil as the pressure-transmitting medium. The applied pressure was measured using the pressure dependence of the superconducting transition temperature of a built-in pressure sensor made of high-purity tin. The magnetic data were calibrated with the sample holder and the diamagnetic contributions.

S3. Refinement

All H atoms were placed geometrically, with C—H = 0.93 (aromatic) or 0.96 Å (CH₂), and refined using a riding-atom model, with U_iso(H) = 1.2U_eq(C).

Computing details

Data collection: CrysAlis CCD (Oxford Diffraction, 2007); cell refinement: CrysAlis RED (Oxford Diffraction, 2007); data reduction: CrysAlis RED (Oxford Diffraction, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXL97 (Sheldrick, 2008) and DIAMOND (Brandenburg, 1999); software used to prepare material for publication: publCIF (Westrip, 2010).

Figures

	Fig. 1. The molecular structure of (I), showing the atom-numbering scheme. Displacement ellipsoids are drawn at the 30% probability level. H atoms and solvent water molecules have been omitted for clarity.
	Fig. 2. A perspective view of the unit cell of (I). [Please supply a new version with atom labels not overlapping bonds and atoms]
	Fig. 3. A perspective view of the πpy–πbenzene and πbenzene–πbenzene interactions between adjacent neutral units of (I). [New version of this figure already requested (SC)]
	Fig. 4. χMT versus T plots of (I) in the temperature range 2–300 K.
	Fig. 5. The thermogravimetric analysis curve for (I).
	Fig. 6. The powder X-ray diffraction spectra for (I).

[bis(pyridin-2-ylmethyl)(quinolin-2-ylmethyl)amine- κ⁴N,N',N'',N''']bis(thiocyanato- κS)iron(II)

Crystal data

[Fe(NCS)2(C22H20N4)]	F(000) = 1056
Mr = 512.45	Dx = 1.391 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
a = 12.2292 (7) Å	Cell parameters from 3037 reflections
b = 11.8350 (6) Å	θ = 2.4–26°
c = 16.9729 (8) Å	µ = 0.81 mm^−1
β = 95.293 (5)°	T = 293 K
V = 2446.1 (2) Å^3	Block, yellow
Z = 4	0.20 × 0.20 × 0.15 mm

Data collection

Oxford Gemini S Ultra diffractometer	4800 independent reflections
Radiation source: fine-focus sealed tube	2639 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.053
Detector resolution: 0 pixels mm^-1	θmax = 26.0°, θmin = 2.4°
ω scans	h = −15→15
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2007)	k = 0→14
Tmin = 0.854, Tmax = 0.887	l = 0→20
13672 measured 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)] = 0.044	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.089	H-atom parameters constrained
S = 0.81	w = 1/[σ^2(Fo^2) + (0.0378P)^2] where P = (Fo^2 + 2Fc^2)/3
4800 reflections	(Δ/σ)max = 0.001
298 parameters	Δρmax = 0.58 e Å^−3
0 restraints	Δρmin = −0.49 e Å^−3

Special details

Experimental. Absorption correction: CrysAlis RED, Oxford Diffraction Ltd., Version 1.171.32.4 (release 27-04-2006 CrysAlis171 .NET) (compiled Apr 27 2007,17:53:11) Empirical absorption correction using spherical harmonics, implemented in SCALE3 ABSPACK scaling algorithm.

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
Fe1	0.31811 (4)	0.21437 (3)	0.20448 (2)	0.03164 (13)
S1	0.28869 (11)	0.54945 (8)	0.04784 (6)	0.0808 (4)
S2	0.69487 (8)	0.22201 (9)	0.13886 (8)	0.0853 (4)
N1	0.37006 (18)	0.2848 (2)	0.32153 (13)	0.0325 (6)
N2	0.1554 (2)	0.1902 (2)	0.24318 (15)	0.0376 (6)
N3	0.26757 (19)	0.06478 (19)	0.12561 (14)	0.0327 (6)
N4	0.3445 (2)	0.06441 (19)	0.28405 (14)	0.0352 (6)
N5	0.2817 (2)	0.3654 (2)	0.14927 (16)	0.0488 (8)
N6	0.4794 (2)	0.2056 (2)	0.17454 (14)	0.0421 (7)
C1	0.3563 (2)	0.3912 (2)	0.34453 (17)	0.0342 (7)
H1	0.3230	0.4420	0.3080	0.041*
C2	0.3889 (2)	0.4295 (3)	0.41929 (18)	0.0395 (8)
H2	0.3787	0.5047	0.4327	0.047*
C3	0.4366 (3)	0.3553 (3)	0.47376 (18)	0.0460 (9)
H3	0.4590	0.3790	0.5249	0.055*
C4	0.4509 (3)	0.2439 (3)	0.45142 (18)	0.0472 (9)
H4	0.4822	0.1915	0.4877	0.057*
C5	0.4182 (2)	0.2119 (3)	0.37461 (17)	0.0367 (7)
C6	0.4348 (3)	0.0949 (2)	0.34394 (18)	0.0455 (9)
H6A	0.5042	0.0912	0.3206	0.055*
H6B	0.4375	0.0414	0.3874	0.055*
C7	0.0662 (3)	0.2517 (3)	0.2193 (2)	0.0517 (9)
H7	0.0758	0.3144	0.1876	0.062*
C8	−0.0365 (3)	0.2289 (4)	0.2380 (3)	0.0748 (13)
H8	−0.0955	0.2747	0.2202	0.090*
C9	−0.0509 (3)	0.1360 (4)	0.2843 (3)	0.0867 (15)
H9	−0.1205	0.1168	0.2978	0.104*
C10	0.0397 (4)	0.0709 (3)	0.3107 (2)	0.0696 (12)
H10	0.0317	0.0081	0.3427	0.084*
C11	0.1422 (3)	0.1009 (3)	0.2889 (2)	0.0439 (9)
C12	0.2436 (3)	0.0372 (3)	0.32149 (19)	0.0494 (9)
H12A	0.2564	0.0527	0.3777	0.059*
H12B	0.2294	−0.0432	0.3154	0.059*
C13	0.2017 (2)	0.0631 (2)	0.05474 (17)	0.0325 (7)
C14	0.1658 (3)	0.1660 (3)	0.02004 (18)	0.0420 (8)
H14	0.1841	0.2339	0.0455	0.050*
C15	0.1039 (3)	0.1660 (3)	−0.05136 (19)	0.0514 (9)
H15	0.0802	0.2342	−0.0741	0.062*
C16	0.0757 (3)	0.0649 (3)	−0.0905 (2)	0.0549 (10)
H16	0.0341	0.0664	−0.1392	0.066*
C17	0.1083 (3)	−0.0345 (3)	−0.05804 (19)	0.0499 (9)
H17	0.0881	−0.1013	−0.0843	0.060*
C18	0.1733 (3)	−0.0390 (3)	0.01574 (19)	0.0394 (8)
C19	0.2102 (3)	−0.1395 (3)	0.0512 (2)	0.0495 (9)
H19	0.1908	−0.2083	0.0274	0.059*
C20	0.2746 (3)	−0.1368 (3)	0.1209 (2)	0.0461 (9)
H20	0.3011	−0.2036	0.1444	0.055*
C21	0.3009 (3)	−0.0330 (2)	0.15699 (18)	0.0366 (8)
C22	0.3763 (3)	−0.0276 (2)	0.23231 (18)	0.0427 (8)
H22A	0.3738	−0.0990	0.2601	0.051*
H22B	0.4511	−0.0157	0.2195	0.051*
C23	0.2845 (3)	0.4418 (3)	0.10731 (19)	0.0426 (9)
C24	0.5695 (3)	0.2129 (3)	0.16036 (17)	0.0374 (8)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Fe1	0.0344 (3)	0.0287 (2)	0.0320 (2)	0.0016 (2)	0.00382 (18)	0.0041 (2)
S1	0.1323 (11)	0.0437 (6)	0.0643 (7)	−0.0029 (6)	−0.0019 (7)	0.0195 (5)
S2	0.0386 (6)	0.0876 (8)	0.1339 (10)	−0.0208 (6)	0.0301 (6)	−0.0701 (8)
N1	0.0354 (15)	0.0307 (14)	0.0322 (13)	0.0058 (13)	0.0079 (11)	0.0050 (13)
N2	0.0334 (16)	0.0371 (16)	0.0422 (16)	0.0040 (13)	0.0031 (12)	−0.0078 (13)
N3	0.0315 (15)	0.0289 (14)	0.0387 (15)	0.0006 (12)	0.0085 (12)	0.0012 (12)
N4	0.0404 (16)	0.0300 (14)	0.0360 (15)	0.0074 (13)	0.0089 (13)	0.0022 (12)
N5	0.070 (2)	0.0332 (16)	0.0413 (17)	−0.0007 (15)	−0.0034 (15)	0.0072 (14)
N6	0.0398 (17)	0.0501 (17)	0.0366 (15)	−0.0088 (16)	0.0052 (13)	−0.0073 (13)
C1	0.0326 (19)	0.0363 (19)	0.0341 (18)	−0.0011 (15)	0.0049 (14)	0.0054 (15)
C2	0.045 (2)	0.0382 (19)	0.0368 (19)	−0.0037 (16)	0.0119 (16)	−0.0019 (16)
C3	0.054 (2)	0.054 (2)	0.0300 (18)	−0.0023 (19)	0.0057 (16)	−0.0028 (17)
C4	0.055 (2)	0.054 (2)	0.0307 (18)	0.0086 (18)	−0.0032 (16)	0.0065 (16)
C5	0.0375 (19)	0.0395 (18)	0.0334 (17)	0.0091 (17)	0.0044 (14)	0.0044 (16)
C6	0.058 (2)	0.045 (2)	0.0331 (19)	0.0173 (18)	0.0008 (17)	0.0036 (16)
C7	0.041 (2)	0.061 (2)	0.052 (2)	0.0121 (19)	−0.0034 (17)	−0.0120 (18)
C8	0.036 (2)	0.096 (4)	0.091 (3)	0.005 (3)	0.001 (2)	−0.026 (3)
C9	0.039 (3)	0.104 (4)	0.121 (4)	−0.025 (3)	0.026 (3)	−0.046 (3)
C10	0.070 (3)	0.056 (3)	0.087 (3)	−0.023 (2)	0.031 (3)	−0.021 (2)
C11	0.043 (2)	0.036 (2)	0.055 (2)	−0.0096 (17)	0.0162 (18)	−0.0173 (17)
C12	0.064 (3)	0.037 (2)	0.051 (2)	−0.0049 (19)	0.0227 (19)	0.0061 (17)
C13	0.0261 (17)	0.0329 (18)	0.0398 (19)	−0.0028 (15)	0.0097 (15)	−0.0017 (15)
C14	0.045 (2)	0.0420 (19)	0.039 (2)	0.0023 (17)	0.0037 (16)	0.0008 (17)
C15	0.054 (2)	0.058 (2)	0.041 (2)	−0.0004 (19)	−0.0020 (18)	0.0013 (18)
C16	0.049 (2)	0.076 (3)	0.039 (2)	0.001 (2)	0.0007 (18)	−0.006 (2)
C17	0.044 (2)	0.064 (3)	0.043 (2)	−0.010 (2)	0.0100 (18)	−0.024 (2)
C18	0.037 (2)	0.0360 (19)	0.047 (2)	−0.0031 (17)	0.0149 (16)	−0.0078 (17)
C19	0.055 (2)	0.039 (2)	0.058 (2)	−0.0133 (19)	0.0220 (19)	−0.0189 (18)
C20	0.057 (2)	0.0271 (19)	0.057 (2)	0.0029 (17)	0.0157 (19)	−0.0033 (17)
C21	0.044 (2)	0.0308 (19)	0.0372 (19)	0.0010 (16)	0.0158 (16)	0.0012 (15)
C22	0.057 (2)	0.0274 (18)	0.044 (2)	0.0084 (17)	0.0098 (17)	0.0048 (15)
C23	0.052 (2)	0.0333 (19)	0.040 (2)	0.0014 (17)	−0.0058 (17)	−0.0044 (16)
C24	0.042 (2)	0.0367 (18)	0.0336 (17)	−0.0091 (19)	0.0031 (15)	−0.0140 (15)

Geometric parameters (Å, º)

Fe1—N5	2.048 (3)	C7—C8	1.352 (5)
Fe1—N6	2.084 (3)	C7—H7	0.9300
Fe1—N2	2.171 (3)	C8—C9	1.372 (6)
Fe1—N1	2.194 (2)	C8—H8	0.9300
Fe1—N4	2.236 (2)	C9—C10	1.390 (5)
Fe1—N3	2.271 (2)	C9—H9	0.9300
S1—C23	1.629 (3)	C10—C11	1.386 (5)
S2—C24	1.612 (3)	C10—H10	0.9300
N1—C1	1.334 (3)	C11—C12	1.513 (4)
N1—C5	1.343 (3)	C12—H12A	0.9700
N2—C11	1.329 (4)	C12—H12B	0.9700
N2—C7	1.342 (4)	C13—C14	1.405 (4)
N3—C21	1.322 (3)	C13—C18	1.406 (4)
N3—C13	1.385 (3)	C14—C15	1.369 (4)
N4—C22	1.474 (4)	C14—H14	0.9300
N4—C12	1.475 (4)	C15—C16	1.395 (4)
N4—C6	1.475 (4)	C15—H15	0.9300
N5—C23	1.153 (4)	C16—C17	1.344 (4)
N6—C24	1.153 (3)	C16—H16	0.9300
C1—C2	1.372 (4)	C17—C18	1.421 (4)
C1—H1	0.9300	C17—H17	0.9300
C2—C3	1.367 (4)	C18—C19	1.389 (4)
C2—H2	0.9300	C19—C20	1.361 (4)
C3—C4	1.387 (4)	C19—H19	0.9300
C3—H3	0.9300	C20—C21	1.397 (4)
C4—C5	1.381 (4)	C20—H20	0.9300
C4—H4	0.9300	C21—C22	1.507 (4)
C5—C6	1.499 (4)	C22—H22A	0.9700
C6—H6A	0.9700	C22—H22B	0.9700
C6—H6B	0.9700
N5—Fe1—N6	95.90 (11)	C8—C7—H7	117.7
N5—Fe1—N2	94.97 (11)	C7—C8—C9	117.8 (4)
N6—Fe1—N2	168.96 (10)	C7—C8—H8	121.1
N5—Fe1—N1	96.63 (9)	C9—C8—H8	121.1
N6—Fe1—N1	92.19 (9)	C8—C9—C10	119.2 (4)
N2—Fe1—N1	88.45 (9)	C8—C9—H9	120.4
N5—Fe1—N4	169.26 (10)	C10—C9—H9	120.4
N6—Fe1—N4	91.17 (10)	C11—C10—C9	119.0 (4)
N2—Fe1—N4	78.35 (9)	C11—C10—H10	120.5
N1—Fe1—N4	74.97 (9)	C9—C10—H10	120.5
N5—Fe1—N3	112.02 (10)	N2—C11—C10	121.4 (3)
N6—Fe1—N3	91.70 (9)	N2—C11—C12	118.0 (3)
N2—Fe1—N3	82.44 (8)	C10—C11—C12	120.4 (3)
N1—Fe1—N3	150.51 (9)	N4—C12—C11	115.1 (3)
N4—Fe1—N3	75.73 (9)	N4—C12—H12A	108.5
C1—N1—C5	118.0 (3)	C11—C12—H12A	108.5
C1—N1—Fe1	126.14 (19)	N4—C12—H12B	108.5
C5—N1—Fe1	115.84 (19)	C11—C12—H12B	108.5
C11—N2—C7	117.9 (3)	H12A—C12—H12B	107.5
C11—N2—Fe1	116.4 (2)	N3—C13—C14	119.1 (3)
C7—N2—Fe1	125.4 (2)	N3—C13—C18	121.3 (3)
C21—N3—C13	118.0 (3)	C14—C13—C18	119.6 (3)
C21—N3—Fe1	112.8 (2)	C15—C14—C13	119.8 (3)
C13—N3—Fe1	128.93 (19)	C15—C14—H14	120.1
C22—N4—C12	111.8 (2)	C13—C14—H14	120.1
C22—N4—C6	111.7 (2)	C14—C15—C16	120.9 (3)
C12—N4—C6	111.1 (2)	C14—C15—H15	119.5
C22—N4—Fe1	104.96 (17)	C16—C15—H15	119.5
C12—N4—Fe1	110.72 (18)	C17—C16—C15	120.3 (3)
C6—N4—Fe1	106.22 (17)	C17—C16—H16	119.9
C23—N5—Fe1	161.6 (3)	C15—C16—H16	119.9
C24—N6—Fe1	172.5 (3)	C16—C17—C18	121.0 (3)
N1—C1—C2	123.3 (3)	C16—C17—H17	119.5
N1—C1—H1	118.4	C18—C17—H17	119.5
C2—C1—H1	118.4	C19—C18—C13	118.4 (3)
C3—C2—C1	118.9 (3)	C19—C18—C17	123.2 (3)
C3—C2—H2	120.6	C13—C18—C17	118.4 (3)
C1—C2—H2	120.6	C20—C19—C18	119.7 (3)
C2—C3—C4	118.9 (3)	C20—C19—H19	120.1
C2—C3—H3	120.6	C18—C19—H19	120.1
C4—C3—H3	120.6	C19—C20—C21	119.5 (3)
C5—C4—C3	119.1 (3)	C19—C20—H20	120.2
C5—C4—H4	120.5	C21—C20—H20	120.2
C3—C4—H4	120.5	N3—C21—C20	122.9 (3)
N1—C5—C4	121.9 (3)	N3—C21—C22	116.5 (3)
N1—C5—C6	115.2 (3)	C20—C21—C22	120.4 (3)
C4—C5—C6	123.0 (3)	N4—C22—C21	111.2 (3)
N4—C6—C5	110.4 (2)	N4—C22—H22A	109.4
N4—C6—H6A	109.6	C21—C22—H22A	109.4
C5—C6—H6A	109.6	N4—C22—H22B	109.4
N4—C6—H6B	109.6	C21—C22—H22B	109.4
C5—C6—H6B	109.6	H22A—C22—H22B	108.0
H6A—C6—H6B	108.1	N5—C23—S1	179.8 (4)
N2—C7—C8	124.6 (4)	N6—C24—S2	178.8 (3)
N2—C7—H7	117.7
N5—Fe1—N1—C1	11.3 (2)	Fe1—N1—C5—C4	−177.4 (2)
N6—Fe1—N1—C1	107.5 (2)	C1—N1—C5—C6	−177.8 (3)
N2—Fe1—N1—C1	−83.5 (2)	Fe1—N1—C5—C6	3.4 (3)
N4—Fe1—N1—C1	−161.8 (2)	C3—C4—C5—N1	−1.8 (5)
N3—Fe1—N1—C1	−155.1 (2)	C3—C4—C5—C6	177.2 (3)
N5—Fe1—N1—C5	−170.0 (2)	C22—N4—C6—C5	158.8 (2)
N6—Fe1—N1—C5	−73.8 (2)	C12—N4—C6—C5	−75.5 (3)
N2—Fe1—N1—C5	95.2 (2)	Fe1—N4—C6—C5	44.9 (3)
N4—Fe1—N1—C5	16.82 (19)	N1—C5—C6—N4	−33.6 (4)
N3—Fe1—N1—C5	23.5 (3)	C4—C5—C6—N4	147.3 (3)
N5—Fe1—N2—C11	−175.3 (2)	C11—N2—C7—C8	−0.4 (5)
N6—Fe1—N2—C11	14.7 (6)	Fe1—N2—C7—C8	173.4 (3)
N1—Fe1—N2—C11	−78.8 (2)	N2—C7—C8—C9	−0.4 (6)
N4—Fe1—N2—C11	−3.8 (2)	C7—C8—C9—C10	1.0 (6)
N3—Fe1—N2—C11	73.1 (2)	C8—C9—C10—C11	−0.7 (6)
N5—Fe1—N2—C7	10.8 (2)	C7—N2—C11—C10	0.7 (4)
N6—Fe1—N2—C7	−159.2 (4)	Fe1—N2—C11—C10	−173.7 (2)
N1—Fe1—N2—C7	107.3 (2)	C7—N2—C11—C12	−175.0 (3)
N4—Fe1—N2—C7	−177.7 (2)	Fe1—N2—C11—C12	10.7 (3)
N3—Fe1—N2—C7	−100.8 (2)	C9—C10—C11—N2	−0.1 (5)
N5—Fe1—N3—C21	173.2 (2)	C9—C10—C11—C12	175.5 (3)
N6—Fe1—N3—C21	76.2 (2)	C22—N4—C12—C11	−106.9 (3)
N2—Fe1—N3—C21	−94.4 (2)	C6—N4—C12—C11	127.5 (3)
N1—Fe1—N3—C21	−21.3 (3)	Fe1—N4—C12—C11	9.7 (3)
N4—Fe1—N3—C21	−14.6 (2)	N2—C11—C12—N4	−13.9 (4)
N5—Fe1—N3—C13	−12.2 (3)	C10—C11—C12—N4	170.4 (3)
N6—Fe1—N3—C13	−109.3 (2)	C21—N3—C13—C14	−179.6 (3)
N2—Fe1—N3—C13	80.1 (2)	Fe1—N3—C13—C14	6.0 (4)
N1—Fe1—N3—C13	153.3 (2)	C21—N3—C13—C18	−1.8 (4)
N4—Fe1—N3—C13	160.0 (3)	Fe1—N3—C13—C18	−176.1 (2)
N5—Fe1—N4—C22	169.6 (5)	N3—C13—C14—C15	177.7 (3)
N6—Fe1—N4—C22	−59.2 (2)	C18—C13—C14—C15	−0.2 (5)
N2—Fe1—N4—C22	117.3 (2)	C13—C14—C15—C16	0.0 (5)
N1—Fe1—N4—C22	−151.1 (2)	C14—C15—C16—C17	0.6 (5)
N3—Fe1—N4—C22	32.27 (19)	C15—C16—C17—C18	−1.0 (5)
N5—Fe1—N4—C12	48.7 (6)	N3—C13—C18—C19	1.9 (4)
N6—Fe1—N4—C12	180.0 (2)	C14—C13—C18—C19	179.8 (3)
N2—Fe1—N4—C12	−3.54 (19)	N3—C13—C18—C17	−178.0 (3)
N1—Fe1—N4—C12	88.0 (2)	C14—C13—C18—C17	−0.2 (4)
N3—Fe1—N4—C12	−88.6 (2)	C16—C17—C18—C19	−179.2 (3)
N5—Fe1—N4—C6	−72.0 (6)	C16—C17—C18—C13	0.7 (5)
N6—Fe1—N4—C6	59.28 (19)	C13—C18—C19—C20	−1.8 (5)
N2—Fe1—N4—C6	−124.22 (19)	C17—C18—C19—C20	178.2 (3)
N1—Fe1—N4—C6	−32.68 (18)	C18—C19—C20—C21	1.5 (5)
N3—Fe1—N4—C6	150.7 (2)	C13—N3—C21—C20	1.5 (4)
N6—Fe1—N5—C23	21.5 (8)	Fe1—N3—C21—C20	176.7 (2)
N2—Fe1—N5—C23	−156.6 (8)	C13—N3—C21—C22	177.5 (3)
N1—Fe1—N5—C23	114.4 (8)	Fe1—N3—C21—C22	−7.3 (3)
N4—Fe1—N5—C23	152.4 (7)	C19—C20—C21—N3	−1.4 (5)
N3—Fe1—N5—C23	−72.8 (8)	C19—C20—C21—C22	−177.2 (3)
C5—N1—C1—C2	0.1 (4)	C12—N4—C22—C21	73.2 (3)
Fe1—N1—C1—C2	178.7 (2)	C6—N4—C22—C21	−161.5 (2)
N1—C1—C2—C3	−0.9 (5)	Fe1—N4—C22—C21	−46.9 (3)
C1—C2—C3—C4	0.3 (5)	N3—C21—C22—N4	38.0 (4)
C2—C3—C4—C5	1.0 (5)	C20—C21—C22—N4	−145.9 (3)
C1—N1—C5—C4	1.3 (4)