Structural disorder and transformation in crystal growth: direct observation of ring-opening isomerization in a metal–organic solid solution

A rare example is reported in which discrete Ag₂L₂ ring and (AgL)_∞ chain motifs [L = N,N′-bis(3-imidazol-1-yl-propyl)-pyromellitic diimide] co-crystallize in the same crystal lattice with varying ratios and degrees of disorder. Crystal structures obtained from representative crystals reveal compatible packing arrangements of the cyclic and polymeric isomers within the crystal lattice, which enables them to co-exist within a crystalline solid solution. A feasible pathway for transformation between the isomers is suggested via facile rotation of the coordinating imidazolyl groups. This chemical system could provide a chance for direct observation of ring-opening isomerization at the crystal surface. Mass spectrometry and ¹H NMR titration show a dynamic equilibrium between cyclic and oligomeric species in solution, and a potential crystallization process is suggested involving alignment of precursors directed by aromatic stacking interactions between pyromellitic diimide units, followed by ring-opening isomerization at the interface between the solid and the solution. Both cyclic and oligomeric species can act as precursors, with interconversion between them being facile due to a low energy barrier for rotation of the imidazole rings. Thermogravimetric analysis and variable-temperature powder X-ray diffraction indicate a transition to a different crystalline phase around 120°C, which is associated with loss of solvent from the crystal lattice.

1. Introduction

The application of design principles that are based on the concepts of self-assembly has over the past decades produced diverse functional crystalline solids possessing important physicochemical properties (e.g. Lehn, 2002; Whitesides & Boncheva, 2002; Janiak, 2003; Mathias & Stoddart, 1992; Cook et al., 2013). Applying these principles to coordination chemistry has also offered chemists opportunities to control the chemical and structural nature of coordination assemblies and, therefore, their functionalities. Two rapidly advancing topics in the field of metal–organic materials (MOMs) include: (1) crystal engineering of metal–organic frameworks (MOFs) or coordination polymers (CPs) that feature in infinite and periodic composite organic/inorganic frameworks (e.g. Kitagawa et al., 2004; Khlobystov et al., 2001; Hagrman et al., 1999; Batten & Robson, 1998; Hosseini, 2005; Ockwig et al., 2005; Wang et al., 2013), and (2) molecular engineering of supramolecular ensembles, such as coordination cages, rings, helicates etc. that are characteristic of finite and discrete structures with well defined shape, size and topology (e.g. Leininger et al., 2000; Fujita et al., 2001; Swiegers & Malefetse, 2000; Caulder & Raymond, 1999; Saalfrank et al., 2000; Turner et al., 2004; Ronson et al., 2013; Chen et al., 2007).

Despite increasing interest in these two promising topics, surprisingly little attention has been paid to the inherent relationship between the finite and infinite systems, although they both obey similar synthetic self-assembly strategies and examples of closely related cyclic and polymeric structures obtained individually from the same metal ions and ligands are known in the literature (e.g. Lozano et al., 2001; Brandys & Puddephatt, 2001; Qin et al., 2002; Puddephatt, 2008; Liang et al., 2009). Insight into this interdisciplinary area between the discrete and extended structures may be able to shed light on the understanding of crystal engineering, in which the growth mechanisms of the periodic crystalline solids of MOFs and CPs remain largely unknown, probably due to their typical insolubility in solvents and the difficulty in determining the degree of polymerization both in solution and in crystal growth. On the contrary, most of the discrete coordination assemblies are detectable in solution. One of the efforts to bridge the finite and infinite analogues has been made by Puddephatt and James, who introduced the term ring-opening polymerization (ROP) to explain the formation of extended structures from discrete cyclic molecular precursors (e.g. Fromm et al., 2005; Miller et al., 2004; Brandys & Puddephatt, 2002; Shin et al., 2003; Abourahma et al., 2002; Lin & Yip, 2006). It is believed that a dynamic equilibrium exists between the discrete species and ring-opened oligomers in solution, while the extended coordination polymers form only on the surface of the growing crystals (e.g. Su, Cai et al., 2003; Chen et al., 2005; Burchell et al., 2003; Paulisse & Sjibesma, 2003). To look for evidence to support this hypothesis, James offered the challenge to `get evidence of ROP at the crystal surface' (James, 2004).

More generally, structural diversification is frequently considered in relation to assembly processes and crystal engineering. Moulton & Zaworotko (2001) proposed the concept of supramolecular isomerism to describe the structural diversity in the realm of CPs, which establishes a way of systematizing and classifying the structures of CPs consisting of identical building blocks in the same ratio but having different crystal structures. Various types of supramolecular isomerism, such as structural isomerism (Hennigar et al., 1997), conformational isomerism (MacGillivray et al., 2001) and topological isomerism (e. g. Blake et al., 2001; Gao et al., 2002), have been reported. In a few cases, mixed isomers co-exist in the same crystal (e.g. Carlucci et al., 2004; Li et al., 2005). To classify supramolecular isomers displaying distinct features of cyclic and polymeric structures, we introduced the term ring-opening isomerism (ROI), which represents a common type of supramolecular isomerism in which the isomers are structurally related to each other by at least one ring-opening transformation (e.g. Su, Goforth et al., 2003; Zhang et al., 2010). ROI can be considered as a structural diversification phenomenon produced via the above-mentioned ROP process.

Previously, we have investigated the dynamics of a series of disilver(I) metallacycles in solution and found that the metal–ligand exchange energy barrier is small and roughly comparable to that of moderate hydrogen bonding (Chen et al., 2005). This result explains why the ROI phenomenon can readily occur in solution, but direct evidence of the ROP process in crystallization is still absent. In this paper we present an interesting example where the ROI phenomenon is observed directly in metal–organic solid solutions, in which both discrete M₂L₂ rings and polymeric (ML)_∞ chains co-crystallize in the same crystal lattice with varying ratios and degrees of order/disorder. The specific packing fashion of the discrete rings and the polymeric chains enables us to understand how the ROP process takes place during crystallization, thus providing a potential prototypical model to demonstrate the ROI phenomenon in crystal growth.

2. Experimental

2.1. Materials and methods

All chemicals were purchased from commercial sources and used without further purification. N,N′-Bis(3-imidazol-1-yl-propyl)-pyromellitic diimide (L, see Fig. 1) was prepared according to the previously described method (Lü et al., 2006). Elemental analyses were carried out on a Perkin–Elmer 240 elemental analyser. IR spectra were obtained on a Bruker EQUINOX55 FT–IR spectrophotometer using KBr discs in the 4000–400 cm⁻¹ region. ¹H NMR measurements were carried out on INOVA 500NB or Mercury-Plus 300 spectrometers with SiMe₄ as internal standard. The powder XRD patterns were recorded on a D/Max-IIIA diffractometer with Cu Kα radiation (λ = 1.5406 Å) at a scanning rate of 1° (2θ) min⁻¹. Thermogravimetric analysis (TGA) was performed in air at a heating rate of 10°C min⁻¹ on a NETZSCH Thermo Microbalance TG 209 F3 Tarsus. The excitation and emission spectra were obtained on a HITACHI 850 spectrometer.

Figure 1 Molecular structure of the ligand L.

2.2. Synthesis of complexes

Complexes {[AgL(CF₃CO₂)]·solvent}_n (1·solvent) in different polymorphic forms were prepared by a general method with varying crystallization times. A solution of AgCF₃CO₂ (13 mg, 0.025 mmol) in tetrahydrofuran (THF; 5 ml) was layered carefully onto a solution of L (22 mg, 0.05 mmol) in CH₂Cl₂ (10 ml) in a test tube. The solutions were left to stand for a few days at room temperature, giving gradual growth of colourless block crystals. Yield: ∼ 54%. IR (KBr, cm⁻¹): 3474w, 3111w, 2944w, 1777m, 1718vs, 1516w, 1456w, 1435w, 1397s, 1362m, 1297w, 1278w, 1238w, 1199m, 1173m, 1130s, 1043w, 1026w, 918w, 883w, 861w, 828w, 799w, 756w, 725m, 657w, 627w, 591w, 559w.

2.3. X-ray crystallography

Several crystals were randomly selected from different crystallization batches and mounted on glass fibres for structural determination, offering two apparent polymorphic forms A (Pbcm) and B (Ibam). All diffraction data were collected on a Bruker Smart 1000 CCD diffractometer with graphite-monochromated Mo Kα radiation (λ = 0.7107 Å) at room temperature using the program SMART and processed by SAINT-Plus (Bruker, 1998). Absorption corrections were applied using SADABS (Bruker, 1998) and the structures were solved by direct methods and refined using full-matrix least-squares against F² using SHELXTL (Sheldrick, 2008). Non-H atoms were refined anisotropically, while H atoms were introduced in calculated positions and refined with fixed geometry with respect to their carrier atoms. For form A, due to poor crystal quality and severe disorder of the anions and solvent molecules, the SQUEEZE procedure (van der Sluis & Spek, 1990) implemented via the WinGX suite (Farrugia, 2012) was applied to account for regions of diffuse electron density that could not be satisfactorily modeled. The coordination frameworks generally display well defined positions; however, disorder of the Ag atoms and methylene imidazole donors is evident. Refinement of the site occupancies of the disordered Ag atoms indicates an 18/82% site distribution, while the disordered methylene imidazole fraction could not be satisfactorily modelled. Some of the C and N atoms exhibiting unusual displacement parameters were refined with SIMU/ISOR restraints in SHELXTL. For form B, the Ag atoms and methylene imidazole donors display statistical disorder over two positions with 50:50% site occupancy. The CF₃CO₂⁻ anions are disordered over two C₂ symmetry-related positions, and modelled using DFIX/SADI restraints. All water solvent molecules were treated with partial occupancy and H atoms were not added. Both the anions and solvents were refined with DELU/SIMU/ISOR restraints. Crystallographic information for data collection and structural refinement is listed in Table 1, and selected bond lengths and angles are listed in Table S1 .

Table 1
Crystallographic data for complex 1 in crystal forms A and B

	Form A	Form B
Crystal data
Chemical formula	C44H40Ag2N12O8	C24H20AgF3N6O11
Mr	1080.62	733.33
Crystal system, space group	Orthorhombic, Pbcm	Orthorhombic, Ibam
a, b, c (Å)	12.6641 (14), 26.230 (3), 35.269 (4)	6.4005 (6), 26.426 (3), 35.016 (3)
V (Å^3)	11715 (2)	5922.5 (10)
μ (mm^−1)	0.72	0.77
Crystal size (mm)	0.40 × 0.40 × 0.16	0.33 × 0.15 × 0.05
Data collection
Tmin, Tmax	0.757, 0.891	0.866, 0.953
No. of measured, independent and observed [I > 2σ(I)] reflections	57 799, 11 087, 4492	14 814, 2801, 1812
Rint	0.095	0.050
(sin θ/λ)max (Å^−1)	0.606	0.606
Refinement
R[F^2> 2σ(F^2)], wR(F^2), S	0.101, 0.233, 1.02	0.091, 0.199, 1.12
No. of reflections	11 087	2801
No. of parameters	621	377
No. of restraints	84	270
Δρmax, Δρmin (e Å^−3)	1.28, −1.52	0.79, −0.51

3. Results and discussion

3.1. Synthesis and X-ray diffraction

The long ditopic, semi-flexible ligand containing a rigid three-fused-ring central base and two imidazole coordinating donors linked by two flexible propylene chains, N,N′-bis(3-imidazol-1-yl-propyl)-pyromellitic diimide (L, see Fig. 1), was prepared by reaction of pyromellitic dianhydride with 2 molar equivalents of N-3-aminopropyl-imidazole in DMF. The reaction of L with AgCF₃CO₂ in the presence of CH₂Cl₂ afforded complexes of the general formula {[AgL(CF₃CO₂)]·solvent}_n (1·solvent). The IR spectrum of the fresh sample indicated the presence of water molecules and CF₃CO₂⁻ anions in the crystals (Fig. S1 ), while ¹H NMR measurements suggested inclusion of CH₂Cl₂ solvent molecules. The relative quantities of the solvents in the crystal were estimated by thermogravimetric analysis (TGA) to be two H₂O and one CH₂Cl₂ molecule per [AgL(CF₃CO₂)]₂ unit (Fig. S2 ). The phase purity of the bulk sample was checked by comparing the measured powder X-ray diffraction (XRD) pattern with the simulations based on the single-crystal structure data (Fig. 2, see below). Solid-state photoluminescent measurements on the pure ligand and complex 1 indicated that the ligand-based emission was strengthened after coordination but keeping a similar peak profile. The emission maximum was red-shifted by 29 nm from 453 nm in the ligand to 482 nm in the complex. These findings suggest that the emission nature of the complex is basically ligand-centred (LC) but may contain a little ligand-to-metal charger-transfer (LMCT) contribution because of the presence of short Ag⋯Ag contacts (see below; Barbieri et al., 2008).

Figure 2 Comparison of powder X-ray diffraction patterns: (a) as-synthesized; (b) simulation based on the refined structure of form B; (c) simulation based on the refined structure of form A. Note that the refined structure of form A does not contain the disordered anions or solvent molecules, so the simulated diffraction pattern is only indicative.

Colourless crystals were readily available from a layered THF–CH₂Cl₂ solvent system in test tubes. Single-crystal X-ray diffraction screening of randomly selected crystals revealed that most of them, although appearing to be optically perfect, had apparently poor crystallinity. Careful structural analyses of a number of single crystals indicated the existence of two main polymorphic forms (Table 1): orthorhombic Pbcm (assigned as form A) and Ibam (assigned as form B). Most crystals probably crystallize in intermediate phases between these two forms, with varying ratios and degrees of disorder depending on the growth conditions. The difficulties are also reflected in the powder XRD patterns of the bulk sample. As seen from Fig. 2, the measured XRD pattern matches well with that simulated from the disordered form B (space group Ibam). The simulated XRD pattern based on form A (space group Pbcm) is only indicative due to omission of the solvent and anions, but all of the observed diffraction peaks also fit well with those of the measured sample. This indicates that the disorder details cannot directly be distinguished from the powder XRD data.

The chemical nature of the two crystal forms A and B can be interpreted as follows. For form B (Ibam), keeping only one or the other Ag atom site from the statistically disordered pair generates ordered crystal structures (both in space group Ibam) comprising only Ag₂L₂ rings or only polymeric (AgL)_∞ chains, respectively. Idealized CIFs corresponding to these structures (rings_Ibam.cif and chains_Ibam.cif) are included in the supporting information for reference. The statistically disordered arrangement of the Ag sites in form B indicates that the two isomers form a solid solution. For form A (Pbcm), considering only the majority (82%) positions for the Ag atoms reveals a structure in which discrete Ag₂L₂ rings and polymeric (AgL)_∞ chains alternate along the crystal a axis. An idealized CIF for this situation (both_Pbcm.cif) is also included in the supporting information . The presence of the second Ag atom site (18% site occupancy) indicates that the structure is part-way between the idealized form A structure and the form B solid solution. Thus, three idealized structures can be envisaged (all rings, all chains, alternating rings/chains along the a axis), and the actual crystals generally adopt structures partway between these.

To examine further the crystallographic origin of the problematic structural analyses, precession images in the a*c* planes of reciprocal space were reconstructed with a thickness of one pixel from the raw CCD area detector images using the CrystAlisPro program (Agilent, 2014). As shown in Fig. 3, diffuse streaks along a* are obvious in the reconstructed h0l and h1l layers for odd values of l, lying between rows of sharp Bragg reflections for even values of l. This indicates that the crystals exhibit one-dimensional disorder along the crystallographic a axis, consistent with an order/disorder type description of the structures (Moulton & Zaworotko, 2001; Bürgi et al., 2001). More detailed examination of the disorder has not been undertaken for this study; the presented interpretation of the crystallographic data is sufficient to describe the observed chemical phenomenon.

Figure 3 Simulated precession images for the h0l (a) and h1l (b) planes for a randomly selected crystal. Diffuse streaks along a* for odd values of l reveal one-dimensional disorder as described in the text.

3.2. Crystal packing and ring-opening isomerism

As shown in Figs. 4(a) and (b), a crystal with the (idealized) structure of form A consists of two clearly distinguishable structural motifs. One is the discrete Ag₂L₂ ring and the other is the polymeric (AgL)_∞ chain. The ring motif comprises two L ligands and two Ag atoms making up a large [Ag₂L₂]²⁺ rectangle with Ag—N bond distances of 2.121 (9) and 2.124 (8) Å, and an N—Ag—N angle of 171.7 (3)°. The polymeric chain comprises [AgL]⁺ repeating units that extend along the c axis with Ag—N bond distances of 2.053 (8) and 2.087 (10) Å, and with an N—Ag—N angle of 176.6 (4)°. There are strong argentophilic interactions between pairs of adjacent chains due to the short Ag⋯Ag contact [3.0776 (17) Å, significantly shorter than the sum of the van der Waals radii for two Ag atoms, 3.44 Å]. These Ag⋯Ag contacts link pairs of chains to form a twisted double-chain structure, exhibiting [(Ag_1/2)₄L₂]²⁺ rectangular subunits sharing two Ag atoms on each side. Such [(Ag_1/2)₄L₂]²⁺ metallacycles show rather similar shape to the [Ag₂L₂]²⁺ ring motifs (Fig. 4 and S4 ), and display similar interior cavity dimensions (8 × 11 Ų). The difference is the orientation of the methylene imidazole donors accompanying the shift of the Ag metal centres.

Figure 4 Structural motifs in the crystal structures of complex 1: (a) Ag2L2 ring and its space-filling model extracted from the (idealized) structure of form A; (b) twisted (AgL)∞ double chains extracted also from form A (dotted lines indicate Ag⋯Ag contacts); (c) Ag2L2 rings and (AgL)∞ double chains co-existing in a disordered fashion in form B. Differently orientated methylene imidazole donors are distinguished by the solid and dotted bonds as well as C atoms in different colours.

Although the crystal quality of form A did not permit clear identification of the disordered methylene imidazole part, free refinement of the Ag site occupancy suggests a minor occupancy (18%) disorder component. This implies that, over the whole crystal lattice, the positions mainly occupied by Ag₂L₂ rings are superimposed by 18% of (AgL)_∞ chains, and vice versa. Such structural disorder and the compatibility of the ring and chain isomers becomes even more clear in the structure of form B. As shown in Fig. 4(c), two methylene imidazole donors in each L ligand can adopt two orientations binding two different Ag atoms with statistical (50:50) occupancy. Therefore, formation of the discrete Ag₂L₂ rings and the polymeric (AgL)_∞ chains appears to have equal probability and can be envisaged to occur in any crystal growth situation. Specifically, the [Ag₂L₂]²⁺ ring has an Ag—N bond distance of 2.134 (7) Å and an N—Ag—N angle of 178.2 (4)°, while the [AgL]⁺ repeating unit in the polymeric chain has an Ag—N bond distance of 2.130 (7) Å and an N—Ag—N angle of 167.8 (4)°. The argentophilic Ag⋯Ag contact is also formed between adjacent chains [3.086 (3) Å]. The disordered site distribution of Ag metal centres and the methylene imidazole donors makes clear that either the Ag₂L₂ ring or (AgL)_∞ chains can be formed and can interconvert through rotation of the imidazole rings while retaining the same syn conformation of the pyromellitic diimide spacers. No matter which of the isomeric structural motifs is formed, the overall coordination skeleton frameworks display the same rectangular shape.

Crucially, the crystal packing in the structures of forms A and B displays generally the same architecture, as seen from Figs. 5 and S5 . If two neighbouring Ag₂L₂ rings in form A are considered to be connected via Ag⋯Ag (3.6 Å) interactions as shown in Fig. 5(a), an extended ribbon of rings is formed along the c axis. Such a ribbon is arranged parallel to the (AgL)_∞ twisted double chain. Furthermore, the one-dimensional ring ribbons and double chains alternately stack along the a axis, resulting in tubular channels made up of [Ag₂L₂]²⁺ rings (belonging to ring ribbons) and [(Ag_1/2)₄L₂]²⁺ metallacycles (belonging to double chains), which are alternately overlapped (Fig. 5b). The compatible crystal packing arrangements of the Ag₂L₂ rings and the double (AgL)_∞ chains provides the circumstances for the observed isomerism and disorder to occur in the crystalline state.

Figure 5 The compatible packing arrangements of the two kinds of structural motifs: (a) the ribbon of rings and the twisted double chains in the structure of form A: (b) the tubular channels running along the a axis formed by alternate packing of rings and chains in a parallel fashion in form A.

Insight into the disorder and crystal polymorphism offers an opportunity to realise how structural transformations between these two kinds of structural motifs could happen during the crystal growth process, which usually occurs in solution but is now manifested directly in the solid state. From the above discussion we realise that since the overall packing of the coordination skeleton frameworks can be kept static while allowing free rotation of the imidazole ring donors about the flexible propylene joints, structural conversion between Ag₂L₂ rings and (AgL)_∞ double chains can readily take place, with the N_imino donors turning from perpendicular to parallel with respect to the central pyromellitic diimide base, and vice versa. As demonstrated in Fig. 6, such rotations can enable ring-opening isomerization between the closed rings and the extended chains (e.g. Su et al., 2003; Zhang et al., 2010). In the solid state, such ring-opening isomerization has to be accompanied by a shift of the Ag centres, while in solution such structural transformation can proceed more easily, especially in the presence of extra Ag⁺ ions (see below). During the structural conversion, the central pyromellitic diimide bases retain the same syn conformation and the Ag centres keep the same linear coordination, so the ring-opening isomerization mediated by rotation of imidazole rings is subject to only minimal energy barriers. This probably accounts for the observations of the highly variable disorder of the crystallized cyclic or polymeric isomers under very similar reaction conditions.

Figure 6 Schematic representation of the ring-opening isomerization process via rotation of the methylene imidazole donors and shift of the Ag centres, resulting in interconversion between discrete rings and polymeric double chains.

The structural transformation speculated above on the basis of the solid-state observations may represent a possible scenario during real crystal growth. One unique feature of the present system is that the crystal polymorphism intrinsically relies on a ring-opening isomerization process. The observed order/disorder phenomenon reflects a highly variable ratio of cyclic and polymeric isomers within one crystal. Therefore, these crystals can be regarded as solid solutions (Yeung et al., 2013) containing varying amounts of the discrete Ag₂L₂ rings and the polymeric (AgL)_∞ chains, as well as the likely presence of finite (AgL)_n oligomers, which is distinct from normal crystal polymorphism and isomerism phenomena (Makal et al., 2011; Jiang, Li et al., 2010; Stahly, 2007; Jiang, Pan et al., 2010; Blagden & Davey, 2003). Formation of such solid solutions may be hypothesized, as illustrated in Fig. 7, to undergo concurrent crystallization and isomerization processes from the solution. In principle, a `molecular library' (Leininger et al., 2000; Lehn & Eliseev, 2001) involving discrete cyclic and oligomeric species (Yue et al., 2005; Masciocchi et al., 1998; Carlucci et al., 1998) may be expected to exist in the reaction solution. During crystallization, this mixture may converge to either discrete rings or polymeric structures, depending on the thermodynamic or kinetic contributions or the presence of specific external influences, such as intermolecular forces, concentration and template effects. Two pathways may be speculated: one is polymerization of the ring-opened species to produce coordination polymers, or reversely, cyclization of the intermediate oligomers to produce discrete rings. In both cases, ring-opening isomerization has to occur. When the ring-opening isomerization is able to take place in a bidirectional way under appropriate conditions, both cyclic and polymeric isomers may co-crystallize in the same crystal, as in the present case (Wheaton et al., 2006). Therefore, we believe that the present example may provide a unique case to shed light on the isomerization process taking place at the crystal surface, namely, structural transformation happening at the interface of the solution and solid during crystallization. Specifically, it is likely that the aromatic stacking forces may direct alignment of the solution precursors on the surface and subsequently enable the formation of either discrete rings or extended chains via ring-opening isomerization. Both cyclic and oligomeric species can act as precursors, and the interconversion between these species may be facile due to a low energy barrier for imidazole ring rotation. Usually the cyclic precursors are thermodynamically favoured in solution; however, formation of the chain structure in the present case may be aided by the argentophilic interactions between the double chains.

Figure 7 Representation of a potential crystallization process in which solid solutions containing discrete rings and coordination polymers of varying ratios are formed from equilibrium solution species via a ring-opening isomerization mechanism.

3.3. Solution studies

To obtain evidence to support the above hypothesis, solution structure investigations were carried out by means of electrospray ionization mass spectrometry (ESI-MS) and ¹H NMR. The ESI-MS spectra of 1 in DMSO or DMF display major peaks, corresponding to [AgL]⁺, [AgL₂]⁺, [Ag₂L₂(CF₃CO₂)]⁺, [Ag₃L₂(CF₃CO₂)₂]⁺ and [Ag₃L₃(CF₃CO₂)₂]⁺ species, as shown in Fig. 8. Each assignment is verified by the isotopic patterns. Further evidence for a molecular library in solution is obtained from the ¹H NMR measurements, which show only one set of proton signals in which all peaks are broadened and shifted relative to those of the `free' ligand. This clearly suggests complexation and rapid metal–ligand exchange on the NMR timescale, consistent with dynamic equilibrium between cyclic and oligomeric species in solution.

Figure 8 Partial ESI-MS spectrum of 1 (upper) and ^1H NMR monitoring (lower) of the titration of AgCF3CO2 by ligand L with varying M:L ratios: (a) pure L, (b) 1:4, (c) 1:2, (d) 2:3, (e) 1:1, (f) 2:1, (g) 3:1 and (h) 4:1 (∼ 90 mM).

To explore the possible distribution of the solution species, the titration of AgCF₃CO₂ with ligand L was monitored by in situ NMR measurements. As shown in Fig. 8, when the M:L ratio is increased from 1:4 to 4:1, a general downfield increase in the proton shift (except that of H₇, see below) relative to the free ligand is observed. Detailed examination reveals that the signal shifts of these aromatic protons show three distinct steps: L:M = 2:1 and 3:2 (Figs. 8c and d), 1:1 and 1:2 (Figs. 8e and f), and 1:3 and 1:4 (Figs. 8g and h). This suggests that in the situation where the ligands are in excess, two- or three-coordinated species such as AgL₂ may predominate in solution. Conversely, when the L:M ratio is closer to or exceeds 1:1, the (AgL)_n oligomeric species may predominate in solution. A slight excess of Ag⁺ in solution may be able to facilitate the isomerization process between cyclic and oligomeric species because the structural interconversion involves not only the rotation of the imidazole rings, but also migration of the Ag⁺ ions. In the presence of additional Ag⁺, such migration may no longer be necessary. On the other hand, when a large excess of Ag⁺ is added (L:M = 1:3 and 1:4), all N donors as well as carbonyl groups (C=O) may be over-surrounded by Ag⁺ ions, which will hinder metal–ligand exchange and cause additional structural changes, thus giving rise to significantly broadened signals.

A striking finding is that while most of the protons are shifted downfield due to a loss of electron density upon coordination (Su, Cai et al., 2003), the signal of H₇, which is located on the central pyromellitic diimide base, is shifted slightly upfield. This hints at the presence of aromatic interactions in the solution similar to the aromatic stacking observed in the solid state. The staggered stacking of pyromellitic diimide in parallel will lead to edge-to-face interactions for H₇, thereby exposing this proton to a ring current shielding effect from the neighbouring molecule (Shetty et al., 1996; Adams et al., 1999; Pang et al., 1999; Zvyagin, 1988). By contrast, the protons on the propylene and imidazole fragment are only subject to electron-withdrawing effects owing to complexation.

3.4. Phase transition in the solid state

Since complex 1 displays the order/disorder phenomenon in the solid state, and structural transformation between the cyclic and polymeric isomers could take place via ring-opening isomerization, it might be expected that heating of the crystals could cause further phase transitions in the solid state. Fig. 9 illustrates variable-temperature powder XRD patterns recorded upon heating and then cooling of the bulk crystals, and Fig. 10 shows differential scanning calorimetry–thermogravimetric analysis (DSC–TGA) curves recorded in the range 25–300°C. From room temperature up to ∼ 110°C, there is a continuous initial weight loss indicative of gradual solvent escape, but the crystal phase remains intact. From ∼ 120°C, the XRD pattern starts to show new diffraction peaks, indicating the appearance of a new crystalline phase. This structural change may be triggered by a relatively abrupt solvent loss as seen from the TGA curve. The transition is irreversible, because the new diffraction pattern was retained when the sample was cooled back to 50°C. Elevating the temperature again from 50 to 250°C revealed that the first phase transition starting around 120°C was completed by ∼ 150°C, where the XRD pattern of complex 1 has been converted to a completely new one and the weight loss reached a stable region on the TGA curve. This new phase is stable up to 180°C and then a drastic structural change occurs around 200°C. The XRD pattern loses all diffraction peaks corresponding to complex 1 and the TGA curve displays a steep weight loss, indicating that the compound becomes principally amorphous, accompanied by evacuation of all remaining solvent from the crystal lattice around 200°C. During these two structural changes (the first crystal-to-crystal phase transition and the second crystal-to-amorphous phase conversion), the coordination framework of complex 1 may not fall apart because the DSC measurement verified that both transitions are endothermic, corresponding to solvent evaporation processes. Decomposition of the framework is observed later, in the temperature region from 300 to 650°C (Fig. S2 ). Attempts to collect single-crystal diffraction data for the new crystal phase around 120°C were not successful, since the crystallinity became poor upon slow heating. A possible reason may be that upon elevating the temperature and releasing the solvent, rotation of the imidazole rings and migration of Ag are promoted in the solid solutions. This would trigger structural transformation between the cyclic and polymeric isomers, although the overall packing arrangement of the ring/chain frameworks remains almost unchanged, thus leading to a crystal-to-crystal phase change. However, since the phase transition is mediated by random movements of the imidazole rings and Ag in the solid state, the disorder along the a axis is likely to become more severe upon heating, thus affording unsatisfactory Bragg reflections and diffraction patterns. In the second structural change around 200°C, the structure may become completely disordered, so as to destroy the three-dimensional crystal lattice.

Figure 9 Variable-temperature powder XRD measurements monitoring the phase transitions: the bulk sample was first heated from room temperature to 120°C, then cooled to 50°C, then heated again to 200°C.

Figure 10 DSC (blue) and TGA (black) curves for complex 1.

4. Conclusions

In summary, we have described a rare example in which Ag₂L₂ ring and (AgL)_∞ chain motifs co-crystallize in varying ratios in the same crystal, showing variable degrees of disorder depending delicately on the crystallization conditions. The structural analysis reveals a straightforward pathway for transformation between the cyclic and polymeric isomers, which can proceed through ring-opening isomerization by facile rotation of the ligand donor groups. Solution structural investigations suggest the existence of a dynamic equilibrium between cyclic and oligomeric species, with aromatic stacking interactions occurring amongst the solution species. Therefore, the crystallization process may be influenced by preferential aromatic stacking of the bulky ligands to direct alignment of coordination precursors on the crystal surface, followed by crystal growth involving ring-opening isomerization at the interface between the solution and the solid. Such ring-opening structural transformation can apparently also occur in the solid state upon heating, which may be the origin of an observed transition between crystalline phases. In general, this chemical system may offer a chance to observe directly ring-opening isomerization at the crystal surface, providing a prototypical model system for understanding of the ring-opening polymerization process, which is usually limited to indirect study of solution systems.

Supporting information

S1. Experimental

S1.1. Refinement

Crystal data, data collection and structure refinement details are summarized in Table 1.

S2. Results and discussion

Computing details

For both compounds, data collection: SMART (Bruker, 1998); cell refinement: SAINT-Plus (Bruker, 1998); data reduction: SAINT-Plus; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008).

Figures

(A_Pbcm)

Crystal data

C44H40Ag2N12O8	Z = 8
Mr = 1080.62	F(000) = 4368
Orthorhombic, Pbcm	Dx = 1.225 Mg m^−3
Hall symbol: -P 2c 2b	Mo Kα radiation, λ = 0.71073 Å
a = 12.6641 (14) Å	µ = 0.72 mm^−1
b = 26.230 (3) Å	T = 293 K
c = 35.269 (4) Å	Plate, colorless
V = 11715 (2) Å^3	0.40 × 0.40 × 0.16 mm

Data collection

Bruker SMART-1000 CCD diffractometer	11087 independent reflections
Radiation source: fine-focus sealed tube	4492 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.095
ω scans	θmax = 25.5°, θmin = 1.2°
Absorption correction: multi-scan SADABS (Bruker, 1998)	h = −15→15
Tmin = 0.757, Tmax = 0.891	k = −20→31
57799 measured reflections	l = −42→33

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F^2 > 2σ(F^2)] = 0.101	H-atom parameters constrained
wR(F^2) = 0.233	w = 1/[σ^2(Fo^2) + (0.031P)^2 + 100.P] where P = (Fo^2 + 2Fc^2)/3
S = 1.01	(Δ/σ)max = 0.006
11087 reflections	Δρmax = 1.28 e Å^−3
621 parameters	Δρmin = −1.52 e Å^−3
84 restraints	Extinction correction: SHELXL, Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.00062 (5)

Special details

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.

Refinement. Refinement of F² against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F², conventional R-factors R are based on F, with F set to zero for negative F². The threshold expression of F² > σ(F²) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F² are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

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

	x	y	z	Uiso*/Ueq	Occ. (<1)
Ag1	0.62671 (7)	0.30867 (3)	−0.00020 (3)	0.0533 (3)	0.819 (2)
Ag2	0.13060 (7)	0.24800 (4)	−0.05127 (3)	0.0578 (3)	0.819 (2)
O1	1.2279 (6)	0.3845 (3)	0.1638 (2)	0.082 (3)
O2	0.9221 (6)	0.4756 (3)	0.16470 (17)	0.0592 (19)
O3	0.0224 (6)	0.3796 (3)	−0.1651 (2)	0.071 (2)
O4	0.3277 (6)	0.4724 (3)	−0.16627 (19)	0.064 (2)
O5	0.4221 (6)	0.0206 (3)	−0.16484 (19)	0.065 (2)
O6	0.7198 (8)	0.1167 (3)	−0.1646 (2)	0.092 (3)
O7	−0.1698 (7)	0.4739 (3)	−0.1651 (2)	0.078 (3)
O8	−0.4703 (6)	0.3768 (4)	−0.1647 (3)	0.101 (3)
N1	0.7378 (7)	0.3126 (4)	0.0434 (3)	0.091 (4)
N2	0.8490 (7)	0.3467 (4)	0.0823 (3)	0.074 (3)
N3	1.0724 (7)	0.4273 (3)	0.1542 (2)	0.050 (2)
N4	0.5185 (7)	0.3094 (3)	−0.0435 (2)	0.055 (2)
N5	0.4051 (7)	0.3427 (4)	−0.0832 (2)	0.073 (3)
N6	0.1741 (6)	0.4253 (3)	−0.1554 (2)	0.050 (2)
N7	0.2434 (7)	0.1882 (3)	−0.0479 (3)	0.065 (3)
N8	0.3525 (8)	0.1296 (3)	−0.0649 (3)	0.068 (3)
N9	0.5666 (7)	0.0712 (3)	−0.1546 (2)	0.058 (2)
N10	0.0170 (7)	0.3070 (4)	−0.0460 (2)	0.071 (3)
N11	−0.0928 (7)	0.3646 (3)	−0.0684 (3)	0.067 (3)
N12	−0.3145 (7)	0.4226 (3)	−0.1547 (2)	0.058 (2)
C1	0.7894 (12)	0.2768 (6)	0.0656 (4)	0.121 (6)
H1A	0.7730	0.2423	0.0653	0.145*
C2	0.7801 (10)	0.3569 (5)	0.0556 (3)	0.074 (3)
H2A	0.7632	0.3892	0.0466	0.089*
C3	0.8598 (10)	0.2953 (5)	0.0861 (3)	0.074 (3)
H3A	0.9089	0.2779	0.1008	0.089*
C4	0.9094 (9)	0.3869 (5)	0.1031 (4)	0.092 (5)
H4A	0.8772	0.4197	0.0979	0.110*
H4B	0.9032	0.3805	0.1301	0.110*
C5	1.0167 (8)	0.3895 (4)	0.0936 (3)	0.056 (3)
H5A	1.0227	0.3937	0.0664	0.067*
H5B	1.0496	0.3573	0.1002	0.067*
C6	1.0793 (9)	0.4330 (4)	0.1131 (3)	0.064 (3)
H6A	1.1527	0.4317	0.1052	0.077*
H6B	1.0505	0.4657	0.1056	0.077*
C7	0.9932 (8)	0.4506 (4)	0.1772 (3)	0.054 (3)
C8	1.0267 (7)	0.4420 (4)	0.2169 (2)	0.043 (2)
C9	1.1262 (6)	0.4154 (3)	0.2168 (3)	0.035 (2)
C10	1.1502 (8)	0.4083 (4)	0.1762 (3)	0.048 (2)
C11	1.1738 (11)	0.4000 (6)	0.2500	0.057 (4)
H11A	1.2348	0.3803	0.2500	0.068*
C12	0.9779 (11)	0.4573 (4)	0.2500	0.043 (3)
H12A	0.9162	0.4766	0.2500	0.052*
C13	0.4803 (8)	0.3514 (5)	−0.0590 (4)	0.073 (4)
H13A	0.5048	0.3839	−0.0532	0.088*
C14	0.3498 (8)	0.3873 (6)	−0.1023 (4)	0.096 (4)
H14A	0.3802	0.4190	−0.0934	0.115*
H14B	0.3602	0.3853	−0.1295	0.115*
C15	0.2330 (8)	0.3864 (5)	−0.0935 (3)	0.081 (4)
H15A	0.2226	0.3907	−0.0664	0.097*
H15B	0.2037	0.3536	−0.1007	0.097*
C16	0.1762 (9)	0.4285 (4)	−0.1146 (3)	0.062 (3)
H16A	0.1038	0.4294	−0.1057	0.075*
H16B	0.2087	0.4606	−0.1077	0.075*
C17	0.1005 (7)	0.3994 (3)	−0.1778 (3)	0.051 (3)
C18	0.1219 (10)	0.4094 (4)	−0.2164 (3)	0.073 (4)
C19	0.2193 (7)	0.4403 (3)	−0.2168 (2)	0.040 (2)
C20	0.2492 (8)	0.4492 (4)	−0.1775 (3)	0.050 (3)
C21	0.2716 (11)	0.4536 (5)	−0.2500	0.049 (4)
H21A	0.3365	0.4702	−0.2500	0.059*
C22	0.0818 (11)	0.3945 (5)	−0.2500	0.048 (3)
H22A	0.0235	0.3730	−0.2500	0.057*
C23	0.3829 (10)	0.2909 (5)	−0.0862 (3)	0.076 (3)
H23A	0.3330	0.2739	−0.1009	0.091*
C24	0.4605 (11)	0.2711 (5)	−0.0598 (4)	0.109 (5)
H24A	0.4698	0.2367	−0.0546	0.131*
C26	0.2830 (9)	0.1648 (4)	−0.0770 (4)	0.079 (4)
H26A	0.2660	0.1713	−0.1022	0.095*
C27	0.2876 (14)	0.1648 (6)	−0.0168 (3)	0.115 (6)
H27A	0.2714	0.1726	0.0082	0.138*
C28	0.3578 (11)	0.1291 (5)	−0.0278 (3)	0.089 (5)
H28A	0.4002	0.1087	−0.0125	0.107*
C29	0.4100 (11)	0.0969 (6)	−0.0938 (4)	0.119 (6)
H29A	0.3922	0.0614	−0.0895	0.143*
H29B	0.3862	0.1059	−0.1190	0.143*
C30	0.5192 (9)	0.1026 (6)	−0.0918 (3)	0.089 (4)
H30A	0.5413	0.1009	−0.0656	0.107*
H30B	0.5384	0.1359	−0.1016	0.107*
C31	0.5769 (8)	0.0616 (5)	−0.1145 (3)	0.079 (4)
H31A	0.6510	0.0614	−0.1076	0.095*
H31B	0.5476	0.0284	−0.1085	0.095*
C32	0.4932 (8)	0.0447 (4)	−0.1761 (3)	0.052 (3)
C33	0.5247 (8)	0.0566 (4)	−0.2169 (3)	0.052 (3)
C34	0.6060 (7)	0.0885 (5)	−0.2180 (3)	0.061 (3)
C35	0.6400 (9)	0.0995 (5)	−0.1772 (3)	0.074 (4)
C36	0.6568 (13)	0.1029 (6)	−0.2500	0.065 (4)
H36A	0.7201	0.1209	−0.2500	0.078*
C37	0.4749 (12)	0.0402 (5)	−0.2500	0.053 (4)
H37A	0.4143	0.0203	−0.2500	0.063*
C39	−0.0220 (8)	0.3305 (5)	−0.0765 (3)	0.067 (3)
H39A	−0.0005	0.3232	−0.1012	0.081*
C40	−0.1079 (12)	0.3622 (5)	−0.0294 (3)	0.096 (5)
H40A	−0.1556	0.3800	−0.0144	0.115*
C41	−0.0321 (12)	0.3256 (5)	−0.0187 (3)	0.111 (6)
H41A	−0.0199	0.3162	0.0063	0.133*
C42	−0.1454 (8)	0.3988 (4)	−0.0945 (3)	0.060 (3)
H42A	−0.1247	0.3911	−0.1203	0.072*
H42B	−0.1261	0.4338	−0.0890	0.072*
C43	−0.2673 (9)	0.3915 (4)	−0.0897 (3)	0.073 (3)
H43A	−0.2865	0.3572	−0.0974	0.087*
H43B	−0.2858	0.3954	−0.0631	0.087*
C44	−0.3294 (9)	0.4299 (4)	−0.1132 (2)	0.056 (3)
H44A	−0.4039	0.4267	−0.1072	0.067*
H44B	−0.3073	0.4641	−0.1063	0.067*
C45	−0.3947 (11)	0.4034 (5)	−0.1756 (4)	0.074 (3)
C46	−0.3563 (7)	0.4104 (4)	−0.2164 (3)	0.049 (2)
C47	−0.2676 (8)	0.4375 (3)	−0.2172 (3)	0.050 (3)
C48	−0.2411 (10)	0.4484 (4)	−0.1764 (3)	0.057 (3)
C49	−0.2161 (13)	0.4504 (5)	−0.2500	0.060 (4)
H49A	−0.1509	0.4667	−0.2500	0.072*
C50	−0.4153 (3)	0.39209 (17)	−0.2500	0.070 (5)
H50	−0.4772	0.3730	−0.2500	0.084*
Ag1'	0.1233 (3)	0.30774 (17)	0.0017	0.143 (4)	0.181 (2)
Ag2'	0.6152 (3)	0.25378 (17)	−0.0544	0.155 (4)	0.181 (2)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Ag1	0.0446 (5)	0.0581 (5)	0.0571 (5)	−0.0022 (5)	−0.0168 (5)	0.0241 (5)
Ag2	0.0520 (5)	0.0529 (5)	0.0685 (6)	0.0080 (5)	0.0020 (5)	0.0277 (5)
O1	0.067 (5)	0.129 (7)	0.051 (5)	0.038 (5)	0.021 (4)	0.007 (5)
O2	0.078 (5)	0.072 (5)	0.027 (4)	0.004 (4)	−0.010 (4)	−0.013 (3)
O3	0.050 (5)	0.093 (6)	0.070 (5)	0.009 (4)	0.014 (4)	0.023 (4)
O4	0.067 (5)	0.073 (5)	0.051 (5)	−0.019 (4)	−0.001 (4)	0.002 (4)
O5	0.052 (5)	0.093 (6)	0.049 (4)	−0.008 (4)	0.011 (4)	−0.001 (4)
O6	0.112 (8)	0.089 (6)	0.073 (6)	−0.007 (6)	−0.030 (5)	−0.011 (5)
O7	0.083 (6)	0.060 (5)	0.092 (6)	−0.039 (5)	−0.010 (5)	−0.002 (4)
O8	0.048 (5)	0.113 (7)	0.143 (8)	−0.039 (5)	0.009 (5)	0.040 (6)
N1	0.055 (6)	0.060 (6)	0.157 (11)	0.018 (5)	−0.048 (7)	−0.020 (7)
N2	0.056 (6)	0.111 (7)	0.056 (5)	−0.001 (6)	−0.012 (5)	−0.023 (5)
N3	0.048 (5)	0.052 (5)	0.049 (5)	0.005 (4)	−0.007 (4)	−0.008 (4)
N4	0.057 (6)	0.063 (6)	0.046 (5)	0.015 (5)	−0.003 (4)	0.016 (4)
N5	0.049 (5)	0.128 (8)	0.043 (5)	0.002 (5)	0.007 (4)	0.034 (5)
N6	0.052 (5)	0.064 (5)	0.034 (5)	−0.007 (4)	−0.004 (4)	0.010 (4)
N7	0.049 (5)	0.054 (6)	0.091 (7)	0.011 (4)	0.007 (5)	0.007 (5)
N8	0.077 (7)	0.065 (6)	0.061 (6)	0.016 (5)	0.000 (5)	−0.013 (5)
N9	0.045 (5)	0.075 (6)	0.054 (6)	0.009 (5)	−0.009 (4)	−0.015 (5)
N10	0.066 (6)	0.095 (7)	0.053 (6)	0.025 (5)	0.008 (5)	0.039 (5)
N11	0.044 (5)	0.072 (6)	0.083 (7)	0.018 (5)	−0.020 (5)	0.027 (5)
N12	0.057 (6)	0.072 (6)	0.046 (5)	−0.010 (5)	0.002 (4)	0.021 (4)
C1	0.125 (13)	0.097 (11)	0.141 (14)	−0.005 (10)	−0.086 (12)	0.044 (10)
C2	0.078 (9)	0.081 (9)	0.064 (8)	0.027 (7)	−0.002 (7)	−0.019 (7)
C3	0.069 (7)	0.076 (7)	0.077 (7)	0.029 (6)	−0.024 (6)	0.008 (6)
C4	0.051 (7)	0.117 (11)	0.108 (10)	0.013 (7)	−0.015 (7)	−0.072 (9)
C5	0.058 (7)	0.071 (7)	0.038 (6)	−0.001 (6)	0.016 (5)	−0.012 (5)
C6	0.069 (8)	0.089 (9)	0.035 (6)	0.001 (6)	0.008 (5)	0.007 (5)
C7	0.043 (6)	0.068 (7)	0.051 (6)	0.012 (5)	−0.016 (5)	−0.004 (5)
C8	0.039 (6)	0.064 (6)	0.027 (5)	0.008 (5)	0.008 (4)	−0.004 (4)
C9	0.019 (4)	0.035 (5)	0.053 (6)	0.001 (4)	−0.004 (4)	−0.010 (4)
C10	0.044 (6)	0.053 (6)	0.047 (6)	−0.022 (5)	0.004 (5)	−0.003 (5)
C11	0.037 (8)	0.071 (10)	0.062 (10)	0.012 (7)	0.000	0.000
C12	0.061 (9)	0.032 (7)	0.037 (7)	0.005 (6)	0.000	0.000
C13	0.042 (7)	0.075 (8)	0.103 (10)	0.007 (6)	−0.016 (7)	0.034 (7)
C14	0.039 (6)	0.143 (10)	0.105 (8)	0.016 (7)	0.017 (6)	0.069 (8)
C15	0.036 (6)	0.127 (11)	0.079 (8)	−0.014 (7)	−0.015 (6)	0.071 (8)
C16	0.061 (7)	0.089 (8)	0.037 (6)	0.035 (6)	0.009 (5)	0.020 (5)
C17	0.028 (5)	0.034 (5)	0.090 (8)	−0.023 (4)	0.012 (5)	0.003 (5)
C18	0.102 (11)	0.067 (7)	0.049 (7)	−0.027 (7)	0.006 (7)	−0.021 (5)
C19	0.038 (5)	0.047 (6)	0.036 (5)	−0.002 (4)	−0.010 (4)	0.004 (4)
C20	0.053 (7)	0.045 (6)	0.052 (7)	−0.007 (5)	0.017 (5)	−0.003 (5)
C21	0.051 (9)	0.047 (8)	0.050 (9)	−0.002 (7)	0.000	0.000
C22	0.051 (9)	0.047 (8)	0.045 (9)	−0.004 (7)	0.000	0.000
C23	0.078 (8)	0.075 (7)	0.074 (7)	0.013 (6)	−0.030 (6)	−0.004 (6)
C24	0.108 (12)	0.066 (8)	0.152 (14)	0.003 (8)	−0.064 (11)	0.016 (9)
C26	0.056 (8)	0.069 (8)	0.113 (11)	0.026 (6)	−0.018 (7)	−0.031 (8)
C27	0.189 (17)	0.119 (12)	0.036 (7)	0.046 (12)	−0.049 (9)	−0.007 (7)
C28	0.127 (12)	0.101 (10)	0.038 (6)	0.057 (9)	−0.030 (7)	0.002 (6)
C29	0.073 (10)	0.161 (15)	0.122 (12)	0.047 (10)	0.011 (9)	−0.073 (11)
C30	0.048 (8)	0.151 (13)	0.068 (8)	0.000 (8)	−0.020 (6)	−0.045 (8)
C31	0.031 (6)	0.118 (11)	0.089 (10)	0.029 (7)	−0.006 (6)	−0.019 (8)
C32	0.042 (6)	0.052 (6)	0.063 (7)	0.012 (5)	0.004 (6)	−0.014 (5)
C33	0.043 (6)	0.074 (7)	0.038 (6)	0.013 (6)	−0.012 (5)	−0.001 (5)
C34	0.014 (5)	0.087 (8)	0.082 (8)	0.014 (5)	−0.013 (5)	−0.006 (6)
C35	0.053 (7)	0.109 (10)	0.061 (8)	−0.039 (7)	0.003 (6)	−0.027 (7)
C36	0.052 (10)	0.056 (10)	0.088 (13)	−0.027 (8)	0.000	0.000
C37	0.062 (10)	0.055 (9)	0.041 (8)	−0.004 (8)	0.000	0.000
C39	0.059 (7)	0.104 (9)	0.039 (6)	0.021 (7)	0.008 (5)	0.037 (6)
C40	0.149 (13)	0.109 (10)	0.030 (6)	0.075 (10)	−0.009 (7)	0.015 (6)
C41	0.156 (14)	0.118 (11)	0.059 (8)	0.099 (11)	0.042 (9)	0.037 (8)
C42	0.052 (7)	0.076 (7)	0.052 (6)	0.001 (6)	0.002 (5)	0.025 (5)
C43	0.075 (8)	0.079 (8)	0.064 (8)	0.007 (7)	0.005 (6)	0.037 (6)
C44	0.077 (8)	0.067 (7)	0.024 (5)	0.000 (6)	0.009 (5)	0.013 (4)
C45	0.070 (8)	0.069 (7)	0.081 (8)	0.037 (6)	0.019 (6)	0.024 (6)
C46	0.019 (4)	0.063 (5)	0.065 (6)	−0.021 (4)	−0.003 (4)	0.005 (4)
C47	0.059 (7)	0.032 (5)	0.057 (7)	−0.008 (5)	0.011 (5)	0.009 (4)
C48	0.077 (9)	0.055 (7)	0.040 (6)	0.011 (6)	0.017 (6)	0.007 (5)
C49	0.060 (10)	0.039 (8)	0.082 (12)	0.007 (7)	0.000	0.000
C50	0.056 (10)	0.063 (10)	0.090 (13)	−0.027 (9)	0.000	0.000
Ag1'	0.080 (4)	0.205 (8)	0.145 (6)	0.005 (5)	−0.010 (4)	−0.141 (6)
Ag2'	0.084 (4)	0.170 (7)	0.212 (8)	0.041 (5)	−0.024 (5)	−0.148 (6)

Geometric parameters (Å, º)

Ag1—N4	2.053 (8)	C12—H12A	0.9300
Ag1—N1	2.087 (10)	C13—H13A	0.9300
Ag1—Ag1^i	3.0776 (17)	C14—C15	1.512 (14)
Ag2—N10	2.121 (9)	C14—H14A	0.9700
Ag2—N7	2.124 (8)	C14—H14B	0.9700
O1—C10	1.244 (11)	C15—C16	1.514 (13)
O2—C7	1.196 (11)	C15—H15A	0.9700
O3—C17	1.204 (10)	C15—H15B	0.9700
O4—C20	1.230 (11)	C16—H16A	0.9700
O5—C32	1.169 (11)	C16—H16B	0.9700
O6—C35	1.192 (12)	C17—C18	1.413 (15)
O7—C48	1.193 (13)	C18—C22	1.346 (12)
O8—C45	1.243 (14)	C18—C19	1.476 (14)
N1—C2	1.351 (14)	C19—C21	1.391 (11)
N1—C1	1.386 (14)	C19—C20	1.454 (13)
N2—C2	1.310 (13)	C21—C19^iii	1.391 (11)
N2—C3	1.360 (14)	C21—H21A	0.9300
N2—C4	1.495 (14)	C22—C18^iii	1.346 (12)
N3—C10	1.349 (12)	C22—H22A	0.9300
N3—C7	1.428 (12)	C23—C24	1.449 (15)
N3—C6	1.459 (12)	C23—H23A	0.9300
N4—C13	1.322 (12)	C24—H24A	0.9300
N4—C24	1.370 (14)	C26—H26A	0.9300
N5—C13	1.299 (13)	C27—C28	1.348 (17)
N5—C23	1.392 (14)	C27—H27A	0.9300
N5—C14	1.520 (14)	C28—H28A	0.9300
N6—C20	1.382 (11)	C29—C30	1.392 (16)
N6—C17	1.400 (12)	C29—H29A	0.9700
N6—C16	1.440 (11)	C29—H29B	0.9700
N7—C26	1.299 (14)	C30—C31	1.527 (15)
N7—C27	1.375 (14)	C30—H30A	0.9700
N8—C28	1.312 (13)	C30—H30B	0.9700
N8—C26	1.345 (13)	C31—H31A	0.9700
N8—C29	1.518 (14)	C31—H31B	0.9700
N9—C32	1.386 (12)	C32—C33	1.527 (14)
N9—C35	1.431 (14)	C33—C34	1.327 (14)
N9—C31	1.443 (14)	C33—C37	1.393 (12)
N10—C41	1.244 (13)	C34—C36	1.352 (13)
N10—C39	1.336 (11)	C34—C35	1.531 (15)
N11—C39	1.299 (13)	C36—C34^iii	1.352 (13)
N11—C40	1.390 (13)	C36—H36A	0.9300
N11—C42	1.446 (12)	C37—C33^iii	1.393 (12)
N12—C45	1.352 (15)	C37—H37A	0.9300
N12—C48	1.380 (13)	C39—H39A	0.9300
N12—C44	1.488 (12)	C40—C41	1.409 (15)
C1—C3	1.245 (16)	C40—H40A	0.9300
C1—H1A	0.9300	C41—H41A	0.9300
C2—H2A	0.9300	C42—C43	1.564 (14)
C3—H3A	0.9300	C42—H42A	0.9700
C4—C5	1.401 (14)	C42—H42B	0.9700
C4—H4A	0.9700	C43—C44	1.524 (13)
C4—H4B	0.9700	C43—H43A	0.9700
C5—C6	1.549 (14)	C43—H43B	0.9700
C5—H5A	0.9700	C44—H44A	0.9700
C5—H5B	0.9700	C44—H44B	0.9700
C6—H6A	0.9700	C45—C46	1.532 (15)
C6—H6B	0.9700	C46—C47	1.330 (12)
C7—C8	1.480 (13)	C46—C50	1.481 (10)
C8—C12	1.381 (11)	C47—C49	1.370 (12)
C8—C9	1.441 (11)	C47—C48	1.506 (14)
C9—C11	1.377 (11)	C49—C47^iii	1.370 (12)
C9—C10	1.478 (13)	C49—H49A	0.9300
C11—C9^ii	1.377 (11)	C50—C46^iii	1.481 (10)
C11—H11A	0.9300	C50—H50	0.9300
C12—C8^ii	1.381 (11)	Ag1'—Ag1'^i	3.031 (9)
N4—Ag1—N1	176.6 (4)	C22—C18—C19	117.9 (11)
N4—Ag1—Ag1^i	90.7 (2)	C17—C18—C19	105.7 (9)
N1—Ag1—Ag1^i	92.6 (3)	C21—C19—C20	129.6 (9)
N10—Ag2—N7	171.7 (3)	C21—C19—C18	122.8 (9)
C2—N1—C1	102.4 (11)	C20—C19—C18	107.4 (8)
C2—N1—Ag1	123.0 (8)	O4—C20—N6	126.7 (10)
C1—N1—Ag1	134.6 (9)	O4—C20—C19	126.6 (9)
C2—N2—C3	110.0 (10)	N6—C20—C19	106.6 (8)
C2—N2—C4	123.2 (12)	C19^iii—C21—C19	114.9 (13)
C3—N2—C4	126.7 (11)	C19^iii—C21—H21A	122.6
C10—N3—C7	110.2 (8)	C19—C21—H21A	122.6
C10—N3—C6	124.3 (9)	C18—C22—C18^iii	123.2 (15)
C7—N3—C6	124.3 (8)	C18—C22—H22A	118.4
C13—N4—C24	104.0 (9)	C18^iii—C22—H22A	118.4
C13—N4—Ag1	124.0 (8)	N5—C23—C24	99.4 (10)
C24—N4—Ag1	131.6 (7)	N5—C23—H23A	130.3
C13—N5—C23	111.7 (10)	C24—C23—H23A	130.3
C13—N5—C14	119.5 (12)	N4—C24—C23	111.8 (11)
C23—N5—C14	128.7 (11)	N4—C24—H24A	124.1
C20—N6—C17	111.0 (8)	C23—C24—H24A	124.1
C20—N6—C16	121.7 (9)	N7—C26—N8	109.0 (12)
C17—N6—C16	127.2 (9)	N7—C26—H26A	125.5
C26—N7—C27	105.2 (11)	N8—C26—H26A	125.5
C26—N7—Ag2	124.4 (8)	C28—C27—N7	110.5 (11)
C27—N7—Ag2	130.4 (9)	C28—C27—H27A	124.7
C28—N8—C26	111.0 (10)	N7—C27—H27A	124.7
C28—N8—C29	129.7 (11)	N8—C28—C27	104.2 (10)
C26—N8—C29	119.3 (11)	N8—C28—H28A	127.9
C32—N9—C35	113.1 (9)	C27—C28—H28A	127.9
C32—N9—C31	120.5 (10)	C30—C29—N8	112.5 (12)
C35—N9—C31	125.2 (9)	C30—C29—H29A	109.1
C41—N10—C39	104.9 (10)	N8—C29—H29A	109.1
C41—N10—Ag2	133.8 (8)	C30—C29—H29B	109.1
C39—N10—Ag2	121.1 (8)	N8—C29—H29B	109.1
C39—N11—C40	106.3 (8)	H29A—C29—H29B	107.8
C39—N11—C42	127.3 (10)	C29—C30—C31	111.9 (11)
C40—N11—C42	126.4 (10)	C29—C30—H30A	109.2
C45—N12—C48	112.8 (9)	C31—C30—H30A	109.2
C45—N12—C44	119.2 (9)	C29—C30—H30B	109.2
C48—N12—C44	124.6 (9)	C31—C30—H30B	109.2
C3—C1—N1	113.7 (13)	H30A—C30—H30B	107.9
C3—C1—H1A	123.1	N9—C31—C30	110.3 (10)
N1—C1—H1A	123.1	N9—C31—H31A	109.6
N2—C2—N1	108.4 (11)	C30—C31—H31A	109.6
N2—C2—H2A	125.8	N9—C31—H31B	109.6
N1—C2—H2A	125.8	C30—C31—H31B	109.6
C1—C3—N2	104.8 (11)	H31A—C31—H31B	108.1
C1—C3—H3A	127.6	O5—C32—N9	127.1 (11)
N2—C3—H3A	127.6	O5—C32—C33	129.2 (10)
C5—C4—N2	114.5 (9)	N9—C32—C33	103.7 (9)
C5—C4—H4A	108.6	C34—C33—C37	121.4 (11)
N2—C4—H4A	108.6	C34—C33—C32	111.0 (9)
C5—C4—H4B	108.6	C37—C33—C32	127.5 (10)
N2—C4—H4B	108.6	C33—C34—C36	124.7 (11)
H4A—C4—H4B	107.6	C33—C34—C35	108.1 (10)
C4—C5—C6	115.3 (9)	C36—C34—C35	126.7 (10)
C4—C5—H5A	108.4	O6—C35—N9	122.8 (12)
C6—C5—H5A	108.4	O6—C35—C34	131.2 (11)
C4—C5—H5B	108.4	N9—C35—C34	104.0 (9)
C6—C5—H5B	108.4	C34^iii—C36—C34	113.0 (14)
H5A—C5—H5B	107.5	C34^iii—C36—H36A	123.5
N3—C6—C5	109.5 (8)	C34—C36—H36A	123.5
N3—C6—H6A	109.8	C33—C37—C33^iii	113.7 (14)
C5—C6—H6A	109.8	C33—C37—H37A	123.2
N3—C6—H6B	109.8	C33^iii—C37—H37A	123.2
C5—C6—H6B	109.8	N11—C39—N10	113.3 (10)
H6A—C6—H6B	108.2	N11—C39—H39A	123.3
O2—C7—N3	123.6 (9)	N10—C39—H39A	123.3
O2—C7—C8	130.3 (10)	N11—C40—C41	101.7 (10)
N3—C7—C8	105.7 (8)	N11—C40—H40A	129.1
C12—C8—C9	122.3 (9)	C41—C40—H40A	129.1
C12—C8—C7	128.9 (9)	N10—C41—C40	113.6 (11)
C9—C8—C7	108.8 (8)	N10—C41—H41A	123.2
C11—C9—C8	121.6 (9)	C40—C41—H41A	123.2
C11—C9—C10	134.3 (9)	N11—C42—C43	108.1 (8)
C8—C9—C10	104.0 (8)	N11—C42—H42A	110.1
O1—C10—N3	124.2 (9)	C43—C42—H42A	110.1
O1—C10—C9	124.4 (9)	N11—C42—H42B	110.1
N3—C10—C9	111.2 (9)	C43—C42—H42B	110.1
C9—C11—C9^ii	116.4 (13)	H42A—C42—H42B	108.4
C9—C11—H11A	121.8	C44—C43—C42	111.6 (8)
C9^ii—C11—H11A	121.8	C44—C43—H43A	109.3
C8^ii—C12—C8	115.5 (12)	C42—C43—H43A	109.3
C8^ii—C12—H12A	122.3	C44—C43—H43B	109.3
C8—C12—H12A	122.3	C42—C43—H43B	109.3
N5—C13—N4	113.1 (11)	H43A—C43—H43B	108.0
N5—C13—H13A	123.4	N12—C44—C43	112.7 (9)
N4—C13—H13A	123.4	N12—C44—H44A	109.1
C15—C14—N5	110.3 (9)	C43—C44—H44A	109.1
C15—C14—H14A	109.6	N12—C44—H44B	109.1
N5—C14—H14A	109.6	C43—C44—H44B	109.1
C15—C14—H14B	109.6	H44A—C44—H44B	107.8
N5—C14—H14B	109.6	O8—C45—N12	128.3 (12)
H14A—C14—H14B	108.1	O8—C45—C46	127.0 (13)
C14—C15—C16	110.7 (9)	N12—C45—C46	103.2 (10)
C14—C15—H15A	109.5	C47—C46—C50	125.6 (9)
C16—C15—H15A	109.5	C47—C46—C45	110.7 (10)
C14—C15—H15B	109.5	C50—C46—C45	123.6 (8)
C16—C15—H15B	109.5	C46—C47—C49	123.6 (11)
H15A—C15—H15B	108.1	C46—C47—C48	105.6 (9)
N6—C16—C15	117.2 (9)	C49—C47—C48	130.9 (10)
N6—C16—H16A	108.0	O7—C48—N12	126.9 (10)
C15—C16—H16A	108.0	O7—C48—C47	126.4 (10)
N6—C16—H16B	108.0	N12—C48—C47	106.7 (10)
C15—C16—H16B	108.0	C47^iii—C49—C47	115.1 (15)
H16A—C16—H16B	107.2	C47^iii—C49—H49A	122.4
O3—C17—N6	123.0 (10)	C47—C49—H49A	122.4
O3—C17—C18	126.7 (11)	C46—C50—C46^iii	106.3 (8)
N6—C17—C18	109.1 (8)	C46—C50—H50	126.9
C22—C18—C17	136.1 (11)	C46^iii—C50—H50	126.9

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

(B_Ibam)

Crystal data

C24H20AgF3N6O11	Z = 8
Mr = 733.33	F(000) = 2944
Orthorhombic, Ibam	Dx = 1.645 Mg m^−3
Hall symbol: -I 2 2c	Mo Kα radiation, λ = 0.71073 Å
a = 6.4005 (6) Å	µ = 0.77 mm^−1
b = 26.426 (3) Å	T = 293 K
c = 35.016 (3) Å	Plate, colorless
V = 5922.5 (10) Å^3	0.33 × 0.15 × 0.05 mm

Data collection

Bruker SMART-1000 CCD diffractometer	2801 independent reflections
Radiation source: fine-focus sealed tube	1812 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.050
ω scans	θmax = 25.5°, θmin = 1.9°
Absorption correction: multi-scan SADABS (Bruker, 1998)	h = −7→7
Tmin = 0.866, Tmax = 0.953	k = −32→31
14814 measured reflections	l = −42→33

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F^2 > 2σ(F^2)] = 0.091	H atoms treated by a mixture of independent and constrained refinement
wR(F^2) = 0.199	w = 1/[σ^2(Fo^2) + (0.0151P)^2 + 93.6532P] where P = (Fo^2 + 2Fc^2)/3
S = 1.12	(Δ/σ)max = 0.001
2801 reflections	Δρmax = 0.79 e Å^−3
377 parameters	Δρmin = −0.51 e Å^−3
270 restraints	Extinction correction: GEOM
Primary atom site location: structure-invariant direct methods

Special details

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.

Refinement. Refinement of F² against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F², conventional R-factors R are based on F, with F set to zero for negative F². The threshold expression of F² > σ(F²) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F² are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

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

	x	y	z	Uiso*/Ueq	Occ. (<1)
O1	2.1882 (9)	0.3659 (2)	0.08630 (17)	0.0828 (18)
O2	1.5864 (8)	0.2748 (2)	0.08524 (14)	0.0650 (15)
C33	1.6975 (16)	0.2941 (4)	0.0000	0.050 (2)
H33A	1.5753	0.2751	0.0000	0.060*
C32	2.0729 (16)	0.3510 (4)	0.0000	0.054 (3)
H32A	2.1952	0.3700	0.0000	0.065*
C31	1.7344 (12)	0.2986 (3)	0.0734 (2)	0.0518 (18)
C30	1.7912 (10)	0.3087 (3)	0.03310 (18)	0.0451 (16)
C29	1.9786 (12)	0.3363 (3)	0.0332 (2)	0.0537 (18)
C28	2.0397 (11)	0.3453 (3)	0.0736 (2)	0.057 (2)
N3	1.8795 (9)	0.3229 (2)	0.09591 (16)	0.0545 (15)
C26	1.8925 (13)	0.3174 (3)	0.1370 (2)	0.071 (2)
H26A	2.0383	0.3171	0.1445	0.085*
H26B	1.8320	0.2851	0.1443	0.085*
N11	1.2212 (11)	0.4404 (3)	0.2044 (2)	0.0650 (18)
C25	1.7804 (14)	0.3595 (4)	0.1584 (2)	0.075 (3)
Ag1	1.0000	0.44162 (6)	0.2500	0.0612 (5)	0.50
N12	1.440 (3)	0.4066 (8)	0.1673 (5)	0.060 (4)	0.50
C11	1.294 (4)	0.3968 (10)	0.1933 (6)	0.064 (6)	0.50
H11A	1.2525	0.3651	0.2019	0.077*	0.50
C12	1.336 (3)	0.4765 (7)	0.1891 (5)	0.089 (6)	0.50
H12A	1.3242	0.5109	0.1944	0.106*	0.50
C13	1.468 (3)	0.4561 (7)	0.1653 (6)	0.083 (6)	0.50
H13A	1.5635	0.4731	0.1498	0.099*	0.50
C14	1.555 (3)	0.3684 (7)	0.1446 (5)	0.060 (5)	0.50
H14A	1.5585	0.3793	0.1181	0.072*	0.50
H14B	1.4793	0.3366	0.1456	0.072*	0.50
Ag2	1.0000	0.5000	0.19795 (5)	0.0650 (5)	0.50
N22	1.438 (3)	0.3819 (7)	0.1829 (6)	0.059 (4)	0.50
C21	1.295 (4)	0.4165 (9)	0.1732 (7)	0.064 (5)	0.50
H21A	1.2517	0.4230	0.1483	0.076*	0.50
C22	1.304 (3)	0.4188 (7)	0.2329 (5)	0.089 (7)	0.50
H22A	1.2781	0.4273	0.2582	0.107*	0.50
C23	1.438 (4)	0.3813 (8)	0.2213 (5)	0.109 (9)	0.50
H23A	1.5137	0.3596	0.2369	0.131*	0.50
C24	1.546 (3)	0.3461 (7)	0.1586 (5)	0.053 (4)	0.50
H24A	1.4902	0.3478	0.1328	0.063*	0.50
H24B	1.5258	0.3119	0.1681	0.063*	0.50
H25B	1.829 (11)	0.3919 (15)	0.1485 (19)	0.063*
H25A	1.803 (12)	0.348 (2)	0.1844 (10)	0.063*
O3	0.938 (5)	0.4873 (10)	0.1226 (7)	0.192 (11)	0.50
O4	1.173 (5)	0.5305 (14)	0.0999 (10)	0.244 (13)	0.50
C34	0.960 (6)	0.515 (2)	0.0864 (14)	0.263 (19)	0.50
C35	0.730 (7)	0.5092 (14)	0.0704 (15)	0.250 (16)	0.50
F1	0.918 (3)	0.5284 (6)	0.0416 (4)	0.279 (8)	0.80
F2	0.609 (10)	0.456 (2)	0.060 (2)	0.205 (15)	0.20
F3	0.797 (7)	0.4518 (12)	0.0571 (12)	0.193 (12)	0.30
F4	0.594 (14)	0.511 (4)	0.0304 (17)	0.38 (5)	0.20
O1W	1.065 (6)	0.3176 (12)	0.2449 (15)	0.158 (11)	0.30
O2W	0.661 (6)	0.4380 (12)	0.0834 (11)	0.134 (10)	0.30
O3W	1.100 (12)	0.261 (3)	0.256 (3)	0.170 (13)	0.20
O4W	1.239 (16)	0.226 (3)	0.236 (3)	0.170 (14)	0.20
O5W	1.233 (13)	0.259 (3)	0.2172 (19)	0.170 (12)	0.25
O6W	0.567 (7)	0.4237 (17)	0.0398 (13)	0.172 (14)	0.25
O7W	0.588 (6)	0.4325 (13)	0.0000	0.191 (12)	0.50
O8W	1.107 (10)	0.2879 (19)	0.2263 (18)	0.169 (12)	0.25
O9W	1.35 (2)	0.262 (5)	0.239 (4)	0.167 (13)	0.15
O10W	1.366 (13)	0.271 (2)	0.213 (2)	0.162 (14)	0.20
O11W	1.134 (17)	0.224 (4)	0.224 (3)	0.172 (15)	0.15

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.053 (4)	0.111 (5)	0.084 (4)	−0.016 (3)	−0.016 (3)	−0.020 (4)
O2	0.063 (3)	0.077 (4)	0.055 (3)	−0.016 (3)	0.006 (3)	−0.007 (3)
C33	0.048 (6)	0.052 (6)	0.050 (6)	−0.007 (5)	0.000	0.000
C32	0.040 (6)	0.055 (6)	0.067 (7)	−0.006 (5)	0.000	0.000
C31	0.050 (4)	0.054 (4)	0.051 (4)	0.003 (4)	0.002 (4)	−0.008 (3)
C30	0.039 (4)	0.051 (4)	0.045 (4)	−0.002 (3)	0.002 (3)	−0.003 (3)
C29	0.050 (4)	0.055 (4)	0.056 (4)	0.001 (4)	−0.004 (4)	−0.007 (3)
C28	0.033 (4)	0.067 (5)	0.070 (5)	0.006 (4)	−0.002 (4)	−0.015 (4)
N3	0.048 (3)	0.069 (4)	0.047 (3)	0.002 (3)	−0.003 (3)	−0.017 (3)
C26	0.055 (5)	0.107 (7)	0.051 (5)	0.019 (5)	−0.009 (4)	−0.018 (5)
N11	0.059 (4)	0.068 (4)	0.069 (4)	0.009 (4)	0.011 (4)	−0.014 (4)
C25	0.052 (5)	0.113 (8)	0.059 (5)	0.003 (5)	−0.007 (4)	−0.034 (6)
Ag1	0.0472 (9)	0.0656 (10)	0.0706 (11)	0.000	0.0203 (9)	0.000
N12	0.040 (9)	0.072 (10)	0.067 (9)	0.004 (8)	−0.004 (7)	−0.016 (8)
C11	0.051 (13)	0.081 (15)	0.061 (14)	−0.020 (12)	0.003 (12)	−0.015 (12)
C12	0.084 (13)	0.067 (11)	0.115 (15)	−0.010 (10)	0.067 (12)	−0.013 (11)
C13	0.066 (12)	0.070 (11)	0.111 (15)	−0.011 (10)	0.036 (11)	−0.014 (10)
C14	0.044 (7)	0.075 (10)	0.061 (10)	0.001 (8)	−0.004 (8)	−0.032 (8)
Ag2	0.0611 (10)	0.0599 (10)	0.0738 (11)	0.0046 (10)	0.000	0.000
N22	0.050 (11)	0.067 (11)	0.061 (11)	0.009 (9)	−0.009 (8)	−0.020 (8)
C21	0.043 (12)	0.094 (16)	0.054 (12)	0.018 (11)	−0.013 (10)	−0.021 (11)
C22	0.142 (19)	0.081 (12)	0.045 (9)	0.053 (13)	0.009 (11)	−0.010 (9)
C23	0.17 (2)	0.120 (16)	0.041 (9)	0.081 (17)	0.006 (12)	−0.007 (10)
C24	0.043 (8)	0.066 (10)	0.049 (9)	0.010 (8)	−0.009 (7)	−0.018 (7)
O3	0.19 (2)	0.170 (18)	0.212 (15)	0.009 (14)	−0.029 (13)	−0.057 (12)
O4	0.241 (18)	0.25 (2)	0.23 (2)	−0.002 (16)	−0.021 (15)	−0.028 (17)
C34	0.25 (2)	0.26 (3)	0.28 (2)	−0.003 (19)	−0.018 (19)	0.011 (18)
C35	0.24 (2)	0.26 (2)	0.25 (2)	−0.019 (19)	−0.023 (17)	0.015 (19)
F1	0.346 (18)	0.289 (15)	0.201 (11)	0.038 (13)	0.010 (13)	−0.010 (11)
F2	0.20 (2)	0.200 (19)	0.21 (2)	0.005 (16)	0.000 (16)	−0.022 (15)
F3	0.189 (19)	0.186 (17)	0.203 (17)	0.005 (15)	0.002 (15)	−0.034 (14)
F4	0.37 (6)	0.38 (6)	0.38 (6)	−0.01 (2)	0.00 (2)	0.01 (2)
O1W	0.15 (2)	0.163 (14)	0.161 (19)	−0.010 (14)	0.010 (16)	0.013 (14)
O2W	0.132 (18)	0.122 (17)	0.149 (15)	0.010 (15)	0.014 (15)	0.016 (14)
O3W	0.17 (2)	0.165 (17)	0.175 (18)	0.000 (17)	0.001 (16)	0.003 (12)
O4W	0.17 (2)	0.170 (16)	0.17 (2)	0.000 (11)	0.002 (14)	0.001 (13)
O5W	0.173 (17)	0.168 (17)	0.171 (17)	−0.001 (11)	−0.003 (11)	−0.002 (13)
O6W	0.16 (2)	0.17 (2)	0.181 (17)	−0.001 (18)	−0.011 (17)	−0.022 (17)
O7W	0.18 (2)	0.20 (2)	0.188 (15)	0.023 (16)	0.000	0.000
O8W	0.165 (16)	0.169 (15)	0.173 (19)	−0.003 (15)	−0.001 (15)	0.003 (13)
O9W	0.171 (15)	0.17 (2)	0.17 (2)	0.003 (12)	0.000 (13)	−0.001 (18)
O10W	0.173 (17)	0.15 (2)	0.16 (2)	0.004 (14)	0.001 (16)	−0.010 (16)
O11W	0.17 (2)	0.168 (15)	0.17 (2)	−0.001 (15)	−0.001 (16)	0.001 (15)

Geometric parameters (Å, º)

O1—C28	1.183 (8)	C14—H14A	0.9700
O2—C31	1.209 (8)	C14—H14B	0.9700
C33—C30	1.361 (8)	Ag2—N11^iii	2.130 (7)
C33—C30^i	1.361 (8)	Ag2—Ag2^ii	3.645 (4)
C33—H33A	0.9300	N22—C21	1.34 (3)
C32—C29^i	1.365 (9)	N22—C23	1.34 (2)
C32—C29	1.365 (9)	N22—C24	1.45 (2)
C32—H32A	0.9300	C21—H21A	0.9300
C31—N3	1.377 (9)	C22—C23	1.37 (2)
C31—C30	1.483 (9)	C22—H22A	0.9300
C30—C29	1.404 (10)	C23—H23A	0.9300
C29—C28	1.487 (10)	C24—H24A	0.9700
C28—N3	1.419 (9)	C24—H24B	0.9700
N3—C26	1.449 (9)	O3—O3^iii	1.04 (5)
C26—C25	1.522 (11)	O3—O4^iii	1.17 (4)
C26—H26A	0.9700	O3—C34^iii	1.43 (5)
C26—H26B	0.9700	O3—C34	1.47 (3)
N11—C22	1.265 (18)	O4—O3^iii	1.17 (4)
N11—C11	1.30 (3)	O4—C34	1.50 (3)
N11—C12	1.318 (17)	O4—C34^iii	1.55 (6)
N11—C21	1.35 (2)	O4—F3^iii	1.58 (5)
N11—Ag2	2.130 (7)	O4—C35^iii	1.60 (5)
N11—Ag1	2.134 (7)	C34—C34^iii	0.94 (11)
C25—C14	1.54 (2)	C34—O3^iii	1.43 (5)
C25—C24	1.54 (2)	C34—O4^iii	1.55 (6)
C25—H25B	0.98 (2)	C34—C35	1.58 (2)
C25—H25A	0.97 (2)	C34—F1	1.63 (5)
Ag1—N11^ii	2.134 (7)	C35—O4^iii	1.60 (5)
Ag1—Ag1^iii	3.086 (3)	C35—F3	1.64 (3)
N12—C13	1.32 (2)	C35—F1	1.65 (3)
N12—C11	1.33 (3)	C35—F4	1.65 (3)
N12—C14	1.48 (3)	C35—F2	1.65 (3)
C11—H11A	0.9300	F2—F3	1.22 (7)
C12—C13	1.31 (2)	F3—O4^iii	1.58 (5)
C12—H12A	0.9300	F4—F4^iv	1.35 (18)
C13—H13A	0.9300
C30—C33—C30^i	116.8 (9)	C21—N22—C23	105 (2)
C30—C33—H33A	121.6	C21—N22—C24	128 (2)
C30^i—C33—H33A	121.6	C23—N22—C24	125.6 (17)
C29^i—C32—C29	116.6 (10)	N22—C21—N11	111 (2)
C29^i—C32—H32A	121.7	N22—C21—H21A	124.7
C29—C32—H32A	121.7	N11—C21—H21A	124.7
O2—C31—N3	125.1 (7)	N11—C22—C23	110.7 (14)
O2—C31—C30	127.7 (7)	N11—C22—H22A	124.7
N3—C31—C30	107.2 (6)	C23—C22—H22A	124.7
C33—C30—C29	121.7 (7)	N22—C23—C22	106.9 (17)
C33—C30—C31	130.7 (7)	N22—C23—H23A	126.6
C29—C30—C31	107.5 (6)	C22—C23—H23A	126.6
C32—C29—C30	121.6 (7)	N22—C24—C25	108.2 (14)
C32—C29—C28	130.4 (7)	N22—C24—H24A	110.1
C30—C29—C28	108.0 (6)	C25—C24—H24A	110.1
O1—C28—N3	124.4 (7)	N22—C24—H24B	110.1
O1—C28—C29	130.0 (8)	C25—C24—H24B	110.1
N3—C28—C29	105.5 (6)	H24A—C24—H24B	108.4
C31—N3—C28	111.5 (6)	O3^iii—O3—O4^iii	137 (2)
C31—N3—C26	124.0 (7)	O3^iii—O3—C34^iii	71 (2)
C28—N3—C26	123.2 (6)	O4^iii—O3—C34^iii	69.7 (14)
N3—C26—C25	112.9 (7)	O3^iii—O3—C34	67 (2)
N3—C26—H26A	109.0	O4^iii—O3—C34	71 (3)
C25—C26—H26A	109.0	C34^iii—O3—C34	38 (5)
N3—C26—H26B	109.0	O3^iii—O4—C34	63 (2)
C25—C26—H26B	109.0	O3^iii—O4—C34^iii	64 (3)
H26A—C26—H26B	107.8	C34—O4—C34^iii	36 (4)
C22—N11—C11	71.7 (14)	O3^iii—O4—F3^iii	147 (4)
C22—N11—C12	114.4 (15)	C34—O4—F3^iii	84 (3)
C11—N11—C12	108.6 (13)	C34^iii—O4—F3^iii	90 (3)
C22—N11—C21	106.4 (13)	O3^iii—O4—C35^iii	114 (4)
C11—N11—C21	38.6 (10)	C34—O4—C35^iii	88 (3)
C12—N11—C21	79.4 (15)	C34^iii—O4—C35^iii	60.4 (17)
C22—N11—Ag2	134.1 (9)	F3^iii—O4—C35^iii	62 (2)
C11—N11—Ag2	149.4 (13)	C34^iii—C34—O3^iii	74 (3)
C12—N11—Ag2	77.9 (9)	C34^iii—C34—O3	68 (3)
C21—N11—Ag2	119.5 (10)	O3^iii—C34—O3	42 (3)
C22—N11—Ag1	72.3 (10)	C34^iii—C34—O4	75 (5)
C11—N11—Ag1	118.4 (11)	O3^iii—C34—O4	47 (2)
C12—N11—Ag1	131.5 (8)	O3—C34—O4	87 (4)
C21—N11—Ag1	147.8 (14)	C34^iii—C34—O4^iii	69 (4)
Ag2—N11—Ag1	68.1 (2)	O3^iii—C34—O4^iii	87 (3)
C26—C25—C14	113.5 (9)	O3—C34—O4^iii	45.4 (18)
C26—C25—C24	106.9 (9)	O4—C34—O4^iii	128 (4)
C14—C25—C24	28.9 (8)	C34^iii—C34—C35	115 (6)
C26—C25—H25B	108 (5)	O3^iii—C34—C35	137 (4)
C14—C25—H25B	93 (5)	O3—C34—C35	100 (3)
C24—C25—H25B	121 (5)	O4—C34—C35	170 (5)
C26—C25—H25A	99 (4)	O4^iii—C34—C35	61 (3)
C14—C25—H25A	119 (5)	C34^iii—C34—F1	106 (2)
C24—C25—H25A	94 (5)	O3^iii—C34—F1	160 (3)
H25B—C25—H25A	125 (7)	O3—C34—F1	157 (3)
N11—Ag1—N11^ii	178.2 (4)	O4—C34—F1	113 (3)
N11—Ag1—Ag1^iii	90.88 (19)	O4^iii—C34—F1	112 (4)
N11^ii—Ag1—Ag1^iii	90.88 (19)	C35—C34—F1	62 (2)
C13—N12—C11	109 (2)	C34—C35—O4^iii	58 (3)
C13—N12—C14	125.3 (17)	C34—C35—F3	87 (4)
C11—N12—C14	126 (2)	O4^iii—C35—F3	58 (2)
N11—C11—N12	107 (2)	C34—C35—F1	61 (2)
N11—C11—H11A	126.7	O4^iii—C35—F1	109 (3)
N12—C11—H11A	126.7	F3—C35—F1	86 (3)
C13—C12—N11	108.7 (15)	C34—C35—F4	142 (5)
C13—C12—H12A	125.6	O4^iii—C35—F4	141 (5)
N11—C12—H12A	125.6	F3—C35—F4	86 (5)
C12—C13—N12	106.6 (17)	F1—C35—F4	82 (4)
C12—C13—H13A	126.7	C34—C35—F2	127 (5)
N12—C13—H13A	126.7	O4^iii—C35—F2	76 (3)
N12—C14—C25	113.5 (13)	F3—C35—F2	43 (3)
N12—C14—H14A	108.9	F1—C35—F2	118 (5)
C25—C14—H14A	108.9	F4—C35—F2	66 (5)
N12—C14—H14B	108.9	C34—F1—C35	57.7 (11)
C25—C14—H14B	108.9	F3—F2—C35	67.9 (16)
H14A—C14—H14B	107.7	F2—F3—O4^iii	91 (5)
N11—Ag2—N11^iii	167.8 (4)	F2—F3—C35	68.7 (16)
N11—Ag2—Ag2^ii	83.90 (19)	O4^iii—F3—C35	59 (2)
N11^iii—Ag2—Ag2^ii	83.90 (19)	F4^iv—F4—C35	117 (5)

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