Crystal structure of μ-cyanido-1:2κ(2) N:C-dicyanido-1κC,2κC-bis-(quinolin-8-amine-1κ(2) N,N')-2-silver(I)-1-silver(II): rare occurrence of a mixed-valence Ag(I,II) compound.

The title dinuclear complex, [Ag2(CN)3(C9H8N2)2], may be considered as an Ag(II) compound with the corresponding metal site coordinated by two bidentate quinolin-8-amine mol-ecules, one cyanide group and one dicyanidoargentate(I) anion, [Ag(CN)2](-). Since this latter ligand contains an Ag(I) atom, the complex should be a class 1 or class 2 mixed-valence compound, according to the Robin-Day classification. The Ag(II) atom is six-coordinated in a highly distorted octa-hedral geometry, while the Ag(I) atom displays the expected linear geometry. In the crystal, the amino groups of the quinolin-8-amine ligands form N-H⋯N hydrogen bonds with the N atoms of the non-bridging cyanide ligands, forming a two-dimensional network parallel to (102). The terminal cyanide ligands are not engaged in polymeric bonds and the title compound is an authentic mol-ecular complex. The title mol-ecule is thus a rare example of a stable Ag(I,II) complex, and the first mixed-valence Ag(I,II) mol-ecular complex characterized by X-ray diffraction.

Chemical context

The coordination chemistry of silver is clearly dominated by AgI complexes. The oxidation state n class="Chemical">AgII, with a paramagnetic 4d 9 electronic configuration, is however present in inorganic species like AgF2, a compound which readily decomposes in water, and is even able to oxidize SiCl4 (Grochala & Mazej, 2015 ▸). AgII is also stable in bimetallic perfluorinated compounds AgII M IVF6, with M = Pt, Pd, Ti, Rh, Sn and Pb. In these solids, the AgII sites are bonded to six F atoms, in an octa­hedral coordination geometry distorted by the Jahn–Teller effect. In contrast, AgO, precipitated from Ag in presence of K2S2O8 in a basic medium, is a diamagnetic mixed-valence AgI,III oxide, rather than a AgII compound (Housecroft & Sharpe, 2012 ▸). Some actual AgII coordination complexes may be formed in solution, for example [Ag(bpy)2]2+, which follows the Curie law with a magnetic moment close to the spin-only value expected for a d 9 system (Kandaiah et al., 2012 ▸).

Recently, polynitrile and cyanido­n class="Chemical">metallate anions have received considerable attention because of their importance in both coordination chemistry and in mol­ecular materials chemistry (Atmani et al., 2008 ▸; Benmansour et al., 2008 ▸, 2009 ▸, 2012 ▸; Setifi et al., 2013 ▸; Setifi, Lehchili et al., 2014 ▸; Setifi, Charles et al., 2014 ▸). In view of the possible roles of these versatile anionic ligands, we have been inter­ested in using them in combination with other chelating or bridging neutral co-ligands to explore their structural and electronic charac­teristics in the extensive field of mol­ecular materials exhib­iting the spin-crossover (SCO) phenomenon (Dupouy et al., 2008 ▸, 2009 ▸; Setifi et al., 2009 ▸; Setifi, Charles et al., 2014 ▸; Setifi, Milin et al., 2014 ▸). During the course of attempts to prepare such complexes, using the di­cyanido­argentate(I) anion, we isolated the title compound, whose structure is described here.

Structural commentary

The title complex (Fig. 1 ▸) is a binuclear silver compound placed in a general position, in which n class="Chemical">metallic sites present contrasting coordination environments. Ag1 is six-coordinated by two quinolin-8-amine bidentate ligands, one terminal cyanide ligand, and one bridging cyanide ligand. The quinoline ring system N1–C8 is slightly twisted, with a r.m.s. deviation of 0.04 Å, while the other, N11–C18, may be considered as planar (rms deviation: 0.01 Å). Quinoline ligands are arranged cis in the octa­hedral coordination polyhedron, and their mean planes make a dihedral angle of 58.71 (5)°. The amino groups bonded to C8 and C18 are trans to the cyanide ligands. The octa­hedral geometry around Ag1 is distorted, mainly because of bite angles for quinoline ligands, N1—Ag1—N9 = 69.59 (7)° and N11—Ag1—N19 = 71.29 (7)°. The coordination of the terminal cyanide ligand, C20 N21 is through the C atom, as determined from the structure refinement (see Refinement section). This orientation seems to be favored by the availability of atom N21 as an acceptor for hydrogen bonding with symmetry-related mol­ecules in the crystal (Table 1 ▸).

Figure 1

The mol­ecular structure of the title complex, with displacement ellipsoids drawn at the 30% probability level.

Table 1

Hydrogen-bond geometry (, )

DHA	DH	HA	D A	DHA
N9H9AN21i	0.79(3)	2.36(3)	3.143(4)	169(3)
N9H9BN21ii	0.85(3)	2.23(3)	3.075(3)	172(3)
N19H19AN21ii	0.77(3)	2.48(3)	3.205(4)	157(3)
N19H19BN25iii	0.90(3)	2.19(3)	3.087(4)	175(3)

Symmetry codes: (i) ; (ii) ; (iii) .

Metal site n class="Gene">Ag2 has a linear coordination with two cyanide ligands. Both ligands are coordinated through their C atoms (C22 and C24), and the coordination angle C22—Ag2—C24 = 176.05 (11)°, close to the ideal angle of 180° expected for an sp hybridization of the metal. Site Ag2 may thus be confidently assigned to a AgI coordination site, and charge balance for the complex should then set the oxidation state for the octa­hedral metal as AgII, with a formal hybridization sp 3 d 2. The title complex is a mixed-valence compound, with valences localized on a single site. According to the Robin–Day classification (Day et al., 2008 ▸), this compound should thus be a class 1 or class 2 mixed-valence compound. The deep-red color of the crystals should be the result of the π*←4d(Ag) metal-to-ligand charge transfer, rather than a consequence of an inter­valence charge transfer of a class 2 complex. Indeed, porphyrinato–AgII compounds are generally purple or red compounds (e.g. Xu et al., 2007 ▸).

Cyanide ligand C22 n class="Chemical">N23 bridges metal sites Ag1 and Ag2, with oxidation states II and I respectively. The best structure refinement shows that this ligand is not disordered: the C atom is bonded to Ag+, and the N atom to the AgII atom. This orientation observed for the bridge is consistent with the Pearson’s HSAB principle (Pearson, 2005 ▸). The cyanide Lewis base is considered as a soft ligand, which preferentially forms covalent bonds with soft Lewis acid, like Ag+. However, the heteronuclear nature of this ligand induces an asymmetric character for the softness: based on the absolute electronegativity criterion, the C side of the cyanide ligand is expected to be softer than the N side. On the other hand, regarding the acid component of the coordination bonds, Ag+ is expected to be softer than Ag2+, due to the charge difference, which makes Ag+ more polarizable than Ag2+. The most stable acid–base inter­actions for the bridging mode of ligand C22 N23 is thus Ag+—C N—Ag2+, as observed in the X-ray-based structure refinement. From the reactivity point of view, the di­cyanido­argentate(I) anion, [Ag(CN)2]−, used as starting material, preserves the κC coordination mode for the cyanide groups in the product. This anion thus acts as a ligand to the oxidized AgII atom formed during the reaction. The same κC coordination is observed for the terminal cyanide group bonded to Ag2+, indicating that this fragment [Ag(CN)]+ is also produced from di­cyanido­argentate, probably prior to amino­quinoline coordination.

Supra­molecular features

As described in the previous section, both terminal cyanide ligands are bonded to n class="Gene">Ag1 and Ag2 as κC ligands, allowing the N terminus to act as acceptor sites for hydrogen bonding (Ramabhadran et al., 2014 ▸). Amino groups of amino­quinoline ligands are the donors for these contacts (Table 1 ▸), forming a two-dimensional supra­molecular network parallel to (102) (Fig. 2 ▸). Mol­ecules are aggregated through a centrosymmetric (8) ring, where the donor group is the terminal cyanide C20/N21 bonded to Ag1. The same cyanide ligand is engaged in (6) rings, where donors are from two different amino groups. This basic pattern of fused rings propagates in the [010] direction, via larger (10) rings. Finally, these rows of mol­ecules are connected in the crystal via the long arms Ag2—C24 N25, which take part in large (19) rings. The shortest metal⋯metal distance is observed in these rings involving Ag+ ions: Ag2⋯Ag2i = 3.9680 (3) Å [symmetry code (i): −x + 2, y + , −z + ].

Figure 2

Part of the crystal structure of the title complex, emphasizing the N—H⋯N hydrogen bonds (dashed red lines) forming R rings. The green mol­ecule corresponds to the asymmetric unit.

Although the resulting supra­molecular structure is compact, hydrogen bonds, with H⋯n class="Chemical">N contacts in the range 2.19 (3)–2.48 (3) Å, should be considered as inter­actions of moderate strength. The crystallized compound is an authentic mol­ecular complex, in which the terminal cyanide ligands are not engaged in polymeric bonds.

Database survey

Complexes characterized by X-ray diffraction which include at least one Ag2+ ion are much less common than Ag+ complexes. An estimation using the field ‘n class="Chemical">NAME = silver(II)’ or ‘NAME = silver(I)’ in the current release of the CSD (version 5.36 with all updates; Groom & Allen, 2014 ▸), affords 63 and more than 8000 hits, respectively. Within AgI complexes, the occurrence of the di­cyanido­argentate ion is significant. It has been used not only as a counter-ion (e.g. Stork et al., 2005 ▸) but also as a ligand for numerous transition-metal ions, including Ag+ (Lin et al., 2005 ▸).

For non-polymeric compounds, the most common coordin­ation for Ag2+ is the square-planar [Agn class="Chemical">N4] arrangement, found in porphyrin derivatives and tetra-aza cyclic ligands (e.g. Xu et al., 2007 ▸). However, a few cases of six-coordinate Ag2+ species have been characterized, with N-donor ligands (Clark et al., 2009 ▸) and S-donor ligands (Shaw et al., 2006 ▸). Compounds with both Ag+ and Ag2+ ions which have been X-ray characterized seem to be very scarce. A 1D polymeric mixed-valent AgI/AgII polymer was obtained by reacting AgNO3, Na2S2O8 and pyrazine in a CH3CN/H2O mixture, and the presence of Ag2+ was confirmed by ESR (Sun et al., 2010 ▸). The two other cases retrieved from the CSD are ionic compounds, in which tetra­aza­cyclo­tetra­decane derivatives coordinate the Ag2+ ion in a square-planar geometry, while the Ag+ ion is present in the anionic polymeric part (Wang & Mak, 2001 ▸) or in an anionic cluster (Wang et al., 2002 ▸). The title complex is, as far we can see, the first non-polymeric and non-ionic mixed-valence AgI,II compound characterized by X-ray diffraction.

Synthesis and crystallization

The title compound was obtained under solvothermal conditions from a mixture of iron(II) sulfate hepta­hydrate (28 mg, 0.1 mmol), quinolin-8-amine (30 mg, 0.2 mmol) and potassium di­cyanido­argentate (40 mg, 0.2 mmol) in n class="Chemical">water–ethanol (4:1 v/v, 20 ml). The mixture was transferred to a Teflon-lined autoclave and heated at 423 K for 48 h. The autoclave was then allowed to cool to ambient temperature. Deep-red crystals of the title compound were collected by filtration, washed with water and dried in air (yield 30%).

Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2 ▸. Special attention was paid to the accurate orientation for the three cyanide ligands in the asymmetric unit. For each C n class="Chemical">N group, two refinements were carried out with each possible orientation, and the best model was retained on the basis of R 1 and wR 2 factors, and ADP for the C and N sites. For example, wR 2 for all data rises from 8.78% to ca. 9.30% if one cyanide ligand bonded to Ag2 is inverted. No evidence for disordered cyanido groups was detected in the difference maps. All C-bonded H atoms were placed in calculated positions and refined as riding atoms, with C—H bond lengths fixed to 0.93 Å. Amino H atoms bonded to N9 and N19 were found in a difference map and refined freely. For all H atoms, isotropic displacement parameters were calculated as U iso(H) = 1.2U eq(carrier atom).

Table 2

Experimental details

Crystal data
Chemical formula	[Ag2(CN)3(C9H8N2)2]
M r	582.15
Crystal system, space group	Monoclinic, P21/c
Temperature (K)	293
a, b, c ()	13.5449(7), 6.9385(3), 22.3824(11)
()	94.767(2)
V (3)	2096.25(17)
Z	4
Radiation type	Mo K
(mm1)	1.89
Crystal size (mm)	0.27 0.23 0.18
Data collection
Diffractometer	Bruker APEXII CCD
Absorption correction	Multi-scan (SADABS; Sheldrick, 2003 ▸)
T min, T max	0.615, 0.754
No. of measured, independent and observed [I > 2(I)] reflections	27103, 7113, 5226
R int	0.021
(sin /)max (1)	0.750
Refinement
R[F 2 > 2(F 2)], wR(F 2), S	0.034, 0.088, 1.02
No. of reflections	7113
No. of parameters	283
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
max, min (e 3)	1.70, 0.56

Computer programs: APEX2 and SAINT (Bruker, 2009 ▸), SHELXS2014/7 (Sheldrick, 2008 ▸), SHELXL2014/7 (Sheldrick, 2015 ▸) and Mercury (Macrae et al., 2008 ▸).

Crystal structure: contains datablock(s) I, global. DOI: 10.1107/S2056989015009664/lh5764sup1.cif

Structure factors: contains datablock(s) I. DOI: 10.1107/S2056989015009664/lh5764Isup2.hkl

CCDC reference: 1401857

Additional supporting information: crystallographic information; 3D view; checkCIF report

[Ag2(CN)3(C9H8N2)2]	F(000) = 1140
Mr = 582.15	Dx = 1.845 Mg m−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
a = 13.5449 (7) Å	Cell parameters from 9889 reflections
b = 6.9385 (3) Å	θ = 3.1–30.7°
c = 22.3824 (11) Å	µ = 1.89 mm−1
β = 94.767 (2)°	T = 293 K
V = 2096.25 (17) Å3	Prism, deep-red
Z = 4	0.27 × 0.23 × 0.18 mm

Bruker APEXII CCD diffractometer	5226 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.021
φ & ω scans	θmax = 32.2°, θmin = 4.2°
Absorption correction: multi-scan (SADABS; Sheldrick, 2003)	h = −20→17
Tmin = 0.615, Tmax = 0.754	k = −7→10
27103 measured reflections	l = −33→32
7113 independent reflections

Refinement on F2	0 constraints
Least-squares matrix: full	Hydrogen site location: mixed
R[F2 > 2σ(F2)] = 0.034	H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.088	w = 1/[σ2(Fo2) + (0.043P)2 + 0.5603P] where P = (Fo2 + 2Fc2)/3
S = 1.02	(Δ/σ)max = 0.001
7113 reflections	Δρmax = 1.70 e Å−3
283 parameters	Δρmin = −0.56 e Å−3
0 restraints

	x	y	z	Uiso*/Ueq
Ag1	0.66686 (2)	0.78323 (2)	0.41853 (2)	0.03575 (6)
Ag2	0.97403 (2)	0.95903 (4)	0.28877 (2)	0.05800 (8)
N1	0.58984 (15)	0.6944 (3)	0.32264 (9)	0.0372 (4)
C2	0.6314 (2)	0.7024 (4)	0.27131 (12)	0.0487 (6)
H2A	0.7001	0.7094	0.2722	0.058*
C3	0.5762 (3)	0.7006 (4)	0.21569 (13)	0.0593 (8)
H3A	0.6080	0.7002	0.1804	0.071*
C4	0.4768 (3)	0.6994 (4)	0.21363 (13)	0.0584 (8)
H4A	0.4397	0.7024	0.1768	0.070*
C4A	0.4286 (2)	0.6937 (3)	0.26690 (12)	0.0470 (6)
C5	0.3257 (2)	0.6965 (4)	0.26830 (17)	0.0631 (9)
H5A	0.2852	0.7052	0.2327	0.076*
C6	0.2850 (2)	0.6865 (4)	0.32116 (19)	0.0682 (9)
H6A	0.2166	0.6928	0.3218	0.082*
C7	0.3441 (2)	0.6670 (4)	0.37504 (15)	0.0552 (7)
H7A	0.3142	0.6564	0.4109	0.066*
C8	0.44478 (18)	0.6633 (3)	0.37580 (11)	0.0382 (5)
C8A	0.48939 (18)	0.6834 (3)	0.32138 (11)	0.0360 (5)
N9	0.50821 (17)	0.6373 (3)	0.42895 (10)	0.0400 (5)
H9A	0.481 (2)	0.675 (4)	0.4567 (14)	0.048*
H9B	0.525 (2)	0.519 (4)	0.4314 (13)	0.048*
N11	0.74947 (17)	0.7366 (3)	0.51431 (9)	0.0445 (5)
C12	0.7454 (2)	0.8572 (4)	0.55930 (13)	0.0617 (8)
H12A	0.7000	0.9578	0.5554	0.074*
C13	0.8057 (3)	0.8419 (5)	0.61242 (14)	0.0682 (9)
H13A	0.8014	0.9322	0.6428	0.082*
C14	0.8705 (2)	0.6948 (4)	0.61937 (14)	0.0597 (8)
H14A	0.9111	0.6831	0.6548	0.072*
C14A	0.87684 (19)	0.5588 (4)	0.57329 (12)	0.0448 (6)
C15	0.9406 (2)	0.4006 (4)	0.57738 (15)	0.0590 (8)
H15A	0.9829	0.3824	0.6118	0.071*
C16	0.9414 (3)	0.2742 (4)	0.53187 (18)	0.0708 (10)
H16A	0.9836	0.1684	0.5354	0.085*
C17	0.8793 (2)	0.3000 (4)	0.47926 (14)	0.0560 (7)
H17A	0.8815	0.2114	0.4482	0.067*
C18	0.81619 (17)	0.4517 (3)	0.47276 (11)	0.0379 (5)
C18A	0.81318 (16)	0.5856 (3)	0.52035 (10)	0.0362 (5)
N19	0.75194 (17)	0.4838 (3)	0.41939 (10)	0.0404 (5)
H19A	0.716 (2)	0.397 (4)	0.4210 (12)	0.048*
H19B	0.788 (2)	0.478 (4)	0.3873 (14)	0.048*
C20	0.6010 (2)	1.0782 (4)	0.44098 (11)	0.0431 (6)
N21	0.5709 (2)	1.2156 (4)	0.45109 (12)	0.0620 (7)
C22	0.8639 (2)	0.9377 (4)	0.34572 (14)	0.0525 (7)
N23	0.8017 (2)	0.9129 (4)	0.37489 (12)	0.0607 (6)
C24	1.0814 (2)	0.9611 (4)	0.23044 (13)	0.0497 (6)
N25	1.1367 (2)	0.9559 (4)	0.19515 (12)	0.0620 (7)

	U11	U22	U33	U12	U13	U23
Ag1	0.03820 (10)	0.03710 (10)	0.03135 (10)	0.00115 (7)	−0.00073 (7)	−0.00062 (7)
Ag2	0.04638 (14)	0.07771 (16)	0.05085 (14)	−0.00800 (10)	0.00974 (10)	0.00022 (10)
N1	0.0449 (11)	0.0354 (10)	0.0311 (10)	0.0019 (8)	0.0019 (8)	−0.0006 (7)
C2	0.0625 (17)	0.0462 (14)	0.0379 (14)	0.0028 (12)	0.0082 (12)	−0.0016 (11)
C3	0.101 (3)	0.0448 (15)	0.0322 (14)	0.0020 (15)	0.0083 (15)	−0.0017 (11)
C4	0.096 (3)	0.0372 (14)	0.0383 (15)	0.0027 (14)	−0.0184 (15)	−0.0002 (11)
C4A	0.0630 (17)	0.0279 (11)	0.0464 (15)	0.0007 (10)	−0.0183 (13)	−0.0006 (10)
C5	0.0601 (19)	0.0490 (16)	0.074 (2)	0.0009 (13)	−0.0320 (17)	0.0012 (14)
C6	0.0419 (17)	0.0603 (19)	0.099 (3)	−0.0001 (13)	−0.0157 (18)	0.0021 (17)
C7	0.0449 (15)	0.0506 (14)	0.071 (2)	−0.0012 (12)	0.0079 (14)	0.0014 (14)
C8	0.0390 (13)	0.0296 (10)	0.0455 (14)	0.0001 (9)	−0.0001 (10)	0.0012 (9)
C8A	0.0457 (13)	0.0225 (9)	0.0383 (13)	0.0021 (8)	−0.0057 (10)	−0.0014 (8)
N9	0.0472 (12)	0.0381 (11)	0.0355 (11)	0.0048 (9)	0.0083 (9)	0.0019 (9)
N11	0.0491 (13)	0.0469 (11)	0.0359 (11)	0.0087 (9)	−0.0062 (9)	−0.0054 (9)
C12	0.074 (2)	0.0592 (17)	0.0497 (17)	0.0210 (15)	−0.0114 (15)	−0.0173 (14)
C13	0.089 (2)	0.0686 (19)	0.0438 (17)	0.0094 (18)	−0.0156 (16)	−0.0194 (15)
C14	0.068 (2)	0.0594 (17)	0.0474 (17)	0.0005 (14)	−0.0217 (14)	−0.0051 (13)
C14A	0.0402 (13)	0.0473 (14)	0.0450 (15)	−0.0041 (10)	−0.0074 (11)	0.0028 (11)
C15	0.0513 (17)	0.0565 (16)	0.065 (2)	0.0051 (13)	−0.0196 (14)	0.0039 (15)
C16	0.064 (2)	0.0536 (17)	0.091 (3)	0.0210 (14)	−0.0199 (18)	−0.0047 (17)
C17	0.0556 (17)	0.0464 (15)	0.0643 (19)	0.0098 (12)	−0.0041 (14)	−0.0121 (13)
C18	0.0334 (12)	0.0390 (12)	0.0408 (13)	−0.0025 (9)	0.0003 (10)	0.0000 (9)
C18A	0.0316 (11)	0.0386 (11)	0.0376 (13)	−0.0018 (9)	−0.0010 (9)	0.0017 (9)
N19	0.0422 (12)	0.0432 (11)	0.0359 (11)	−0.0028 (8)	0.0041 (9)	−0.0047 (9)
C20	0.0539 (15)	0.0388 (13)	0.0365 (13)	−0.0039 (11)	0.0025 (11)	0.0045 (10)
N21	0.0785 (19)	0.0514 (14)	0.0581 (16)	0.0082 (13)	0.0184 (14)	0.0060 (12)
C22	0.0526 (17)	0.0500 (15)	0.0553 (18)	−0.0087 (12)	0.0074 (14)	−0.0033 (12)
N23	0.0626 (16)	0.0563 (14)	0.0659 (17)	−0.0120 (12)	0.0221 (13)	−0.0064 (12)
C24	0.0423 (15)	0.0592 (16)	0.0470 (16)	0.0007 (12)	−0.0004 (13)	0.0082 (12)
N25	0.0548 (15)	0.0745 (17)	0.0581 (17)	0.0054 (12)	0.0119 (13)	0.0138 (12)

Ag1—C20	2.305 (3)	N9—H9A	0.79 (3)
Ag1—N23	2.323 (3)	N9—H9B	0.85 (3)
Ag1—N11	2.357 (2)	N11—C12	1.314 (3)
Ag1—N19	2.375 (2)	N11—C18A	1.357 (3)
Ag1—N1	2.3878 (19)	C12—C13	1.389 (4)
Ag1—N9	2.404 (2)	C12—H12A	0.9300
Ag2—C24	2.033 (3)	C13—C14	1.347 (4)
Ag2—C22	2.047 (3)	C13—H13A	0.9300
N1—C2	1.322 (3)	C14—C14A	1.406 (4)
N1—C8A	1.361 (3)	C14—H14A	0.9300
C2—C3	1.398 (4)	C14A—C15	1.395 (4)
C2—H2A	0.9300	C14A—C18A	1.419 (3)
C3—C4	1.343 (5)	C15—C16	1.345 (5)
C3—H3A	0.9300	C15—H15A	0.9300
C4—C4A	1.407 (4)	C16—C17	1.400 (4)
C4—H4A	0.9300	C16—H16A	0.9300
C4A—C5	1.397 (4)	C17—C18	1.357 (3)
C4A—C8A	1.415 (3)	C17—H17A	0.9300
C5—C6	1.347 (5)	C18—C18A	1.417 (3)
C5—H5A	0.9300	C18—N19	1.436 (3)
C6—C7	1.397 (5)	N19—H19A	0.77 (3)
C6—H6A	0.9300	N19—H19B	0.90 (3)
C7—C8	1.363 (4)	C20—N21	1.069 (3)
C7—H7A	0.9300	C22—N23	1.121 (4)
C8—C8A	1.411 (4)	C24—N25	1.133 (4)
C8—N9	1.420 (3)
C20—Ag1—N23	94.56 (9)	C8—N9—Ag1	110.41 (15)
C20—Ag1—N11	94.96 (8)	C8—N9—H9A	109 (2)
N23—Ag1—N11	96.04 (9)	Ag1—N9—H9A	114 (2)
C20—Ag1—N19	166.25 (8)	C8—N9—H9B	108.5 (19)
N23—Ag1—N19	86.81 (9)	Ag1—N9—H9B	100.1 (19)
N11—Ag1—N19	71.29 (7)	H9A—N9—H9B	114 (3)
C20—Ag1—N1	106.09 (8)	C12—N11—C18A	118.8 (2)
N23—Ag1—N1	91.27 (8)	C12—N11—Ag1	124.28 (18)
N11—Ag1—N1	157.10 (7)	C18A—N11—Ag1	116.52 (16)
N19—Ag1—N1	87.54 (7)	N11—C12—C13	123.3 (3)
C20—Ag1—N9	89.30 (9)	N11—C12—H12A	118.4
N23—Ag1—N9	160.78 (9)	C13—C12—H12A	118.4
N11—Ag1—N9	102.39 (8)	C14—C13—C12	119.2 (3)
N19—Ag1—N9	93.89 (8)	C14—C13—H13A	120.4
N1—Ag1—N9	69.59 (7)	C12—C13—H13A	120.4
C24—Ag2—C22	176.05 (11)	C13—C14—C14A	120.2 (3)
C2—N1—C8A	118.8 (2)	C13—C14—H14A	119.9
C2—N1—Ag1	125.78 (18)	C14A—C14—H14A	119.9
C8A—N1—Ag1	113.24 (15)	C15—C14A—C14	123.7 (3)
N1—C2—C3	122.6 (3)	C15—C14A—C18A	119.2 (2)
N1—C2—H2A	118.7	C14—C14A—C18A	117.1 (2)
C3—C2—H2A	118.7	C16—C15—C14A	120.5 (3)
C4—C3—C2	119.4 (3)	C16—C15—H15A	119.8
C4—C3—H3A	120.3	C14A—C15—H15A	119.8
C2—C3—H3A	120.3	C15—C16—C17	120.8 (3)
C3—C4—C4A	120.4 (3)	C15—C16—H16A	119.6
C3—C4—H4A	119.8	C17—C16—H16A	119.6
C4A—C4—H4A	119.8	C18—C17—C16	121.2 (3)
C5—C4A—C4	123.6 (3)	C18—C17—H17A	119.4
C5—C4A—C8A	119.4 (3)	C16—C17—H17A	119.4
C4—C4A—C8A	117.0 (3)	C17—C18—C18A	119.1 (2)
C6—C5—C4A	120.0 (3)	C17—C18—N19	122.9 (2)
C6—C5—H5A	120.0	C18A—C18—N19	118.1 (2)
C4A—C5—H5A	120.0	N11—C18A—C18	119.3 (2)
C5—C6—C7	121.1 (3)	N11—C18A—C14A	121.5 (2)
C5—C6—H6A	119.4	C18—C18A—C14A	119.2 (2)
C7—C6—H6A	119.4	C18—N19—Ag1	113.75 (15)
C8—C7—C6	120.8 (3)	C18—N19—H19A	100 (2)
C8—C7—H7A	119.6	Ag1—N19—H19A	112 (2)
C6—C7—H7A	119.6	C18—N19—H19B	109.0 (19)
C7—C8—C8A	119.2 (2)	Ag1—N19—H19B	108.9 (17)
C7—C8—N9	123.2 (3)	H19A—N19—H19B	113 (3)
C8A—C8—N9	117.6 (2)	N21—C20—Ag1	179.5 (3)
N1—C8A—C8	119.1 (2)	N23—C22—Ag2	174.7 (3)
N1—C8A—C4A	121.6 (2)	C22—N23—Ag1	163.6 (2)
C8—C8A—C4A	119.2 (2)	N25—C24—Ag2	175.2 (3)
C8A—N1—C2—C3	0.2 (3)	C18A—N11—C12—C13	2.2 (5)
Ag1—N1—C2—C3	−161.74 (19)	Ag1—N11—C12—C13	−170.2 (3)
N1—C2—C3—C4	3.0 (4)	N11—C12—C13—C14	−1.4 (6)
C2—C3—C4—C4A	−2.1 (4)	C12—C13—C14—C14A	0.1 (6)
C3—C4—C4A—C5	178.5 (3)	C13—C14—C14A—C15	−178.8 (3)
C3—C4—C4A—C8A	−1.9 (3)	C13—C14—C14A—C18A	0.3 (5)
C4—C4A—C5—C6	178.6 (3)	C14—C14A—C15—C16	178.7 (3)
C8A—C4A—C5—C6	−1.0 (4)	C18A—C14A—C15—C16	−0.4 (5)
C4A—C5—C6—C7	−2.1 (5)	C14A—C15—C16—C17	0.9 (6)
C5—C6—C7—C8	2.0 (5)	C15—C16—C17—C18	−0.6 (5)
C6—C7—C8—C8A	1.3 (4)	C16—C17—C18—C18A	−0.2 (4)
C6—C7—C8—N9	−177.8 (3)	C16—C17—C18—N19	179.5 (3)
C2—N1—C8A—C8	176.2 (2)	C12—N11—C18A—C18	178.3 (3)
Ag1—N1—C8A—C8	−19.6 (2)	Ag1—N11—C18A—C18	−8.7 (3)
C2—N1—C8A—C4A	−4.4 (3)	C12—N11—C18A—C14A	−1.7 (4)
Ag1—N1—C8A—C4A	159.72 (16)	Ag1—N11—C18A—C14A	171.31 (18)
C7—C8—C8A—N1	175.0 (2)	C17—C18—C18A—N11	−179.4 (3)
N9—C8—C8A—N1	−5.8 (3)	N19—C18—C18A—N11	0.9 (3)
C7—C8—C8A—C4A	−4.3 (3)	C17—C18—C18A—C14A	0.6 (4)
N9—C8—C8A—C4A	174.9 (2)	N19—C18—C18A—C14A	−179.2 (2)
C5—C4A—C8A—N1	−175.2 (2)	C15—C14A—C18A—N11	179.7 (3)
C4—C4A—C8A—N1	5.2 (3)	C14—C14A—C18A—N11	0.5 (4)
C5—C4A—C8A—C8	4.2 (3)	C15—C14A—C18A—C18	−0.3 (4)
C4—C4A—C8A—C8	−175.4 (2)	C14—C14A—C18A—C18	−179.5 (2)
C7—C8—N9—Ag1	−153.5 (2)	C17—C18—N19—Ag1	−172.6 (2)
C8A—C8—N9—Ag1	27.4 (2)	C18A—C18—N19—Ag1	7.2 (3)

D—H···A	D—H	H···A	D···A	D—H···A
N9—H9A···N21i	0.79 (3)	2.36 (3)	3.143 (4)	169 (3)
N9—H9B···N21ii	0.85 (3)	2.23 (3)	3.075 (3)	172 (3)
N19—H19A···N21ii	0.77 (3)	2.48 (3)	3.205 (4)	157 (3)
N19—H19B···N25iii	0.90 (3)	2.19 (3)	3.087 (4)	175 (3)