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Separating n‐butene and iso‐butene through adsorption represents a viable and energy‐efficient strategy. However, developing porous adsorbents that can effectively discern the subtle differences between these isomers remains a significant challenge. This study demonstrates that a zinc‐based coordination network (CALF‐20) exhibits a slight pore expansion with increasing temperature, creating nanochannels that preferentially adsorb n‐butene over iso‐butene. This unique temperature‐dependent dynamic behavior enables effective sieving of n‐butene from iso‐butene within the temperature range of 273 to 423 K, a phenomenon not previously observed. Notably, CALF‐20 exhibits the highest n‐butene adsorption capacity (2.62 mmol g−1) and the highest selectivity ratio (14.7) among sieving materials reported to date for n‐butene isomers. Modeling calculations show that dynamic factors play a significant role in achieving such high adsorption separation capabilities. At medium temperatures, the initial separation of n‐butene and iso‐butene is achievable, which may provide a foundation for the future design of adsorbents intended to achieve efficient separation of n‐butene/iso‐butene under comparable temperature conditions. In the future, the intricate structure dynamics and enhanced capacity for molecular recognition will offer a new pathway for developing advanced sieving materials. [ABSTRACT FROM AUTHOR]

The proton conductivity of two coordination networks, [Mg(H2O)2(H3L)]·H2O and [Pb2(HL)]·H2O (H5L = (H2O3PCH2)2-NCH2-C6H4-SO3H), is investigated by AC impedance spectroscopy. Both materials contain the same phosphonato-sulfonate linker molecule, but have clearly different crystal structures, which has a strong effect on proton conductivity. In the Mg-based coordination network, dangling sulfonate groups are part of an extended hydrogen bonding network, facilitating a “proton hopping” with low activation energy; the material shows a moderate proton conductivity. In the Pb-based metal-organic framework, in contrast, no extended hydrogen bonding occurs, as the sulfonate groups coordinate to Pb2+, without forming hydrogen bonds; the proton conductivity is much lower in this material.

Reactions between Co(NCS)2 and 24,24‐[2,5‐bis(cyclohexyloxy)‐1,4‐phenylene]di(13,22 : 26,33‐terpyridine) (1), 24,24‐[2,5‐bis(cyclohexylmethoxy)‐1,4‐phenylene]di(13,22 : 26,33‐terpyridine) (2), and 24,24‐[2,5‐bis(2‐phenylethoxy)‐1,4‐phenylene]di(13,22 : 26,33‐terpyridine) (3) under conditions of crystal growth by layering at room temperature lead to 3‐dimensional nets with either a cds or trinodal self‐penetrating topology depending upon the solvents (MeOH/C6H5Cl, MeOH/1,2‐Cl2C6H5, or MeOH/CHCl3) used in the crystallization experiments. The cds network was found for [Co(NCS)2(1)]n⋅2nC6H4Cl2, [Co(NCS)2(2)]n⋅4nC6H4Cl2, and [Co(NCS)2(3)]n⋅2.5nC6H5Cl, while a trinodal self‐penetrating net was observed in [Co2(NCS)4(2)2]n⋅5.5nCHCl3⋅0.2nMeOH. Preliminary structural data for single crystals from the reactions of Co(NCS)2 and 1 or Co(NCS)2 and 3 from MeOH/CHCl3 solvent combinations also evidenced the assemblies of trinodal self‐penetrating nets. Both net topologies assemble from a combination of planar, 4‐connecting metal and ligand nodes. The role of the solvent in directing the network type is investigated. [ABSTRACT FROM AUTHOR]

The consistent assembly of a (65.8) cds net is observed in reactions of cobalt(II) thiocyanate with 1,4-bis(n-alkyloxy)-2,5-bis(3,2′:6′,3″-terpyridin-4′-yl)benzene ligands in which the n-alkyloxy substituents are n-propyl (ligand 3), n-butyl (4), n-pentyl (5), n-hexyl (6), n-heptyl (7), and n-octyl (8). Crystals were grown by layering a methanol solution of Co(NCS)2 over a 1,2-dichlorobenzene solution of each ligand. The choice of crystallization solvents is critical in directing the assembly of the cds net. Single-crystal structures of [Co(NCS)2(3)]n.3.5nC6H4Cl2, [Co(NCS)2(4)]n.5.5nC6H4Cl2, [Co(NCS)2(5)]n.4nC6H4Cl2, [Co(NCS)2(6)]n.3.8nC6H4Cl2, [Co(NCS)2(7)]n.3.1nC6H4Cl2, and [Co(NCS)2(8)]n.1.6nC6H4Cl2.2nMeOH (C6H4Cl2 = 1,2-dichlorobenzene) are presented and compared. The n-alkyloxy chains exhibit close to extended conformations and are accommodated in cavities in the lattice without perturbation of the coordination framework. [ABSTRACT FROM AUTHOR]

The consistent assembly of a (65.8) cds net is observed in reactions of cobalt(II) thiocyanate with 1,4-bis(n-alkyloxy)-2,5-bis(3,2′:6′,3″-terpyridin-4′-yl)benzene ligands in which the n-alkyloxy substituents are n-propyl (ligand 3), n-butyl (4), n-pentyl (5), n-hexyl (6), n-heptyl (7), and n-octyl (8). Crystals were grown by layering a methanol solution of Co(NCS)2 over a 1,2-dichlorobenzene solution of each ligand. The choice of crystallization solvents is critical in directing the assembly of the cds net. Single-crystal structures of [Co(NCS)2(3)]n.3.5nC6H4Cl2, [Co(NCS)2(4)]n.5.5nC6H4Cl2, [Co(NCS)2(5)]n.4nC6H4Cl2, [Co(NCS)2(6)]n.3.8nC6H4Cl2, [Co(NCS)2(7)]n.3.1nC6H4Cl2, and [Co(NCS)2(8)]n.1.6nC6H4Cl2.2nMeOH (C6H4Cl2 = 1,2-dichlorobenzene) are presented and compared. The n-alkyloxy chains exhibit close to extended conformations and are accommodated in cavities in the lattice without perturbation of the coordination framework.

The synthesis and characterization of six new lanthanide networks [Ln(L)(ox)(H2O)] with Ln = Eu3+, Gd3+, Tb3+, Dy3+, Ho3+ and Yb3+ is reported. They were synthesized by solvo-ionothermal reaction of lanthanide nitrate Ln(NO3)3·xH2O with the 1,3-bis(carboxymethyl)imidazolium [HL] ligand and oxalic acid (H2ox) in a water/ethanol solution. The crystal structure of these compounds has been solved on single crystals and the magnetic and luminescent properties have been investigated relying on intrinsic properties of the lanthanide ions. The synthetic strategy has been extended to mixed lanthanide networks leading to four isostructural networks of formula [Tb1−xEux(L)(ox)(H2O)] with x = 0.01, 0.03, 0.05 and 0.10. These materials were assessed as luminescent ratiometric thermometers based on the emission intensities of ligand, Tb3+ and Eu3+. The best sensitivities were obtained using the ratio between the emission intensities of Eu3+ (5D0→7F2 transition) and of the ligand as the thermometric parameter. [Tb0.97Eu0.03(L)(ox)(H2O)] was found to be one of the best thermometers among lanthanide-bearing coordination polymers and metal-organic frameworks, operative in the physiological range with a maximum sensitivity of 1.38%·K−1 at 340 K.

Calcium phosphate-based bone cements have been widely adopted in both orthopedic and dental applications. Phosphoserine (pSer), which has a natural role in biomineralization, has been identified to possess the functionality to react with calcium phosphate phases, such as tetracalcium phosphate (TTCP) and α-tricalcium phosphate (α-TCP), and form a uniquely adhesive cement. This study investigated the chemical composition and phase evolution of a heterogeneous calcium phosphate (56% TTCP and 15% α-TCP) and pSer cement system with respect to pH. The coordination network of calcium phosphoserine monohydrate was discovered as the predominant crystalline phase of this adhesive apatitic cement system. Furthermore, it was determined that pH has a significant effect on the reaction kinetics of the system, whereby a lower pH tends to accelerate the reaction rate and favor products with lower Ca/P ratios. These findings provide a better understanding of the reaction and products of this adhesive organo-ceramic cement, which can be compositionally tuned for broad applications in the orthopedic and dental spaces. The application of self-setting calcium phosphate cements (CPCs) in hard tissue regeneration has been a topic of significant research since their introduction to the field 30 years ago. Traditional CPCs, however, are limited by their suboptimal mechanical properties due to their solely inorganic composition. Recently, it was discovered that monomeric phosphoserine (pSer) is capable of serving as a setting reagent for a subset of CPC systems, resulting in an adhesive organo-ceramic composite. Despite its adhesive functionality and biomedical potential, its reaction chemistry and product composition were not well characterized. The present study identifies a calcium phosphoserine coordination network as the primary crystalline phase of this apatitic cement system and further characterizes compositional tunability of the products with respect to pH. Image, graphical abstract [ABSTRACT FROM AUTHOR]

Introducing FeII-crosslinking ligands into a cyanido-bridged FeII–NbIV assembly provides a spin crossover compound, which exhibits a gradual and incomplete spin crossover. The calculation indicates that the spin transition occurs sparsely, rather than forming low spin site domains. [Display omitted] • A three-dimensional cyanido-bridged Fe-Nb assembly is synthesized. • The three-dimensional coordination network contains both cyanido- and dipyridyldisulfide-bridges. • This compound shows a gradual and incomplete spin crossover. • The calculation suggests the spin transition occurs sparsely. A cyanido-bridged FeII-NbIV spin-crossover complex, [FeII(dpds) 2 ] 2 [NbIV(CN) 8 ]·6H 2 O (dpds = 4,4′-dipyridyldisulfide), is synthesized with a three-dimensional coordination network. The network has cyanido bridges to connect the FeII and NbIV sites and dpds as an additional ligand to crosslink the FeII sites. [FeII(dpds) 2 ] 2 [NbIV(CN) 8 ]·6H 2 O exhibits a gradual and incomplete spin crossover in which 22% of the high-spin FeII sites change to low-spin FeII sites as the temperature decreases. The calculation indicates that the spin transition occurs sparsely, rather than forming low spin site domains. [ABSTRACT FROM AUTHOR]

We overview the coordination chemistry of ditopic and tetratopic ligands with 4,2':6',4''-terpyridine metal-binding domains and illustrate the adaptability of these divergent ligands as building blocks in 2D- and 3D-coordination networks. The ditopic ligands we discuss are limited to roles as linkers in coordination assemblies, while the tetratopic ligands have the potential to be 4-connecting nodes. Both di- and tetratopic ligands are equipped with functionalities, typically alkyloxy chains, the nature of which has a profound effect upon the coordination assembly. Combinations of 4-connecting ligand nodes with metal-linkers lead to both 2D- and 3D-networks, while combinations of 4-connecting metal and ligand nodes give 3D-architectures. We also demonstrate constraint of the coordination assembly to 2-dimensions by depositing ditopic 4,2':6',4"-terpyridine ligands onto Au(111) or Cu(111) platforms with Cu adatoms in the former case; highly ordered ladder assemblies result which are independent of solvent molecules or anions.

The use of divergent 4,2′:6′,4″- and 3,2′:6′,3″-terpyridine ligands as linkers and/or nodes in extended coordination assemblies has gained in popularity over the last decade. However, there is also a range of coordination polymers which feature 2,2′:6′,2″-terpyridine metal-binding domains. Of the remaining 45 isomers of terpyridine, few have been utilized in extended coordination arrays. Here, we provide an overview of coordination polymers and networks containing isomers of terpyridine and either zinc(II) and cadmium(II). Although the motivation for investigations of many of these systems is their luminescent behavior, we have chosen to focus mainly on structural details, and we assess to what extent assemblies are reproducible. We also consider cases where there is structural evidence for competitive product formation. A point that emerges is the lack of systematic investigations.

The polyaniline (PANI) was assembled onto unsaturated sites of Cu-based metal–organic frameworks (Cu-MOF) via coordination-driven to form a coordination network nanoparticle, Cu-BDC-F@PANI. The Cu-BDC-F@PANI crosslinked with PVDF to fabricate Cu-BDC-F@PANI/PVDF facilitated transport hybrid membranes (FTHMs). With the fabulous microenvironment and numerous activated N-Cu(II) sites, the highly performances of Cu-BDC-F@PANI/PVDF membranes yield excellent permeance and favorable selectivity for CO 2. [Display omitted] • The Cu-BDC-F@PANI/PVDF FTHMs was synthesized by coordination-driven strategy. • Molecular dynamic simulations were performed to verify the filler-matrix compatibility. • Cu-BDC-F@PANI/PVDF with even distribution filler exhibits high permeance and selectivity for CO 2. • The membrane shows robust decomposition temperature and lasting sustainability. MOFs-based facilitated transport hybrid membranes (FTHMs) have shown their great potential in CO 2 -selective gas separation. However, rational membrane fabrication by distributing evenly and introducing functional groups in MOFs-based facilitated transport hybrid membrane is crucial but challenging. We herein report a facile coordination-driven approach to realize the integration of polyaniline (PANI) grafted Cu-MOFs onto a polymeric matrix through Cu(II)-N coordination interaction. The resulting facilitated membrane exhibited synergetic channels to process CO 2 -facilitated transport due to the CO 2 -philic nature of PANI and MOFs with low-density pore blockage observed. The even distribution of well-dispersed MOFs nanoparticles upon PANI is realized through coordination interaction between the metal center and amino and imine groups in PANI. Moreover, PANI is highly compatible with the polymeric matrix by forming hydrogen bonds, as verified by experimental characterization and molecular dynamics (MD) simulations. The resulting FTHMs exhibit a simultaneous enhancement of individual-gas permeance (676.6 GPU) and CO 2 /N 2 ideal selectivity (28.3), as well as enhanced decomposition temperature up to 474 °C and lasting sustainability over 72 days (1728 h). The coordination-driven membrane fabrication paves a new and promising way for designing stable, uniform, and longevity FTHMs, thus offering a potential facile route to fabricate high-performance FTHMs for CO 2 /N 2 separation. [ABSTRACT FROM AUTHOR]

Recent IUPAC (The International Union for Pure and Applied Chemistry) recommendations on the terminology of metal-organic frameworks are reviewed and the background to a proposed topology classification is discussed. The various numerical designators such as point symbols, vertex symbols and transitivity are also explained and their importance elucidated.

Pyridin-2-ylmethanols (hmp) and 1, 3-propanediols have been proven to be successful ligands for constructing high-spin manganese clusters. In this work, both ligands are merged into one framework, resulting in a new tridentate ligand 4-chloro-2-(hydroxy(pyridin-2-yl)methyl)phenol. Its initial attempt in Mn coordination chemistry harvested a Mn III dimer [Mn III 2 (L) 2 (AcAc) 2 ] and a 2-D honeycomb network based on star-shaped [Mn II Mn III 3 ] tetramer {[Mn II Mn III 3 (Na) 1.5 (L) 6 ](OH) 0.5 ·(MeOH) 1.5 } n . The two clusters were characterized by single crystal X-ray diffraction, IR spectra, elemental analysis, and magnetic measurements. Magnetic studies revealed dominant ferromagnetic interactions within the Mn III dimer and star-shaped [Mn II Mn III 3 ] tetramer unit. [ABSTRACT FROM AUTHOR]

Ditopic, 4,2′:6′,4′′-terpyridine (4,2′:6′,4′′-tpy) and 3,2′:6′,3′′-terpyridine (3,2′:6′,3′′-tpy) present a divergent N,N′-donor set (the central N atom typically being non-coordinated) and are ideal building blocks for the assembly of coordination polymers and networks. The step from ditopic to tetratopic ligands which contain two interconnected 4,2′:6′,4′′-tpy or 3,2′:6′,3′′-tpy metal-binding domains renders the ligand capable of acting as a 4-connecting node and is a successful route to increasing the dimensionality of the assembly. In this short overview, we illustrate the recent development of the use of bis(4,2′:6′,4′′-tpy) and bis(3,2′:6′,3′′-tpy) ligands and compare strategies using either ditopic or tetratopic ligands. [ABSTRACT FROM AUTHOR]

A series of new group 2 coordination polymers, MgL ={MgL(H2O)(DMF)0.75}∞, CaL = {CaL(DMF)2}∞, SrL = {SrL(H2O)0.5}∞ and BaL = {BaL(H2O)0.5}∞, were synthesized using a flexible benzimidazolone diacetic acid linker (H2L) in which the two carboxylic acid binding sites are connected to a planar core via {–CH2–} spacers that can freely rotate in solution. In a ‘curiosity-led' diversion from group 2 metals, the first row transition metal salts Mn2+, Cu2+ and Zn2+ were also reacted with L to yield crystals of MnL = {MnL(DMF)(H2O)3.33}∞, Cu3L2 = {Cu3L2(DMF)2(CHO2)2}∞ and ZnL = {ZnL(DMF)}∞. Crystal structures were obtained for all seven materials. All structures form as two-dimensional sheets and contain six-coordinate centres, with the exception of ZnL, which displays tetrahedrally coordinated metal centres, and Cu3L2, which contains square planar coordinated metal centres and Cu paddle-wheels. In each structure, the linker adopts one of two distinct conformations, with the carboxylate groups either cis or trans with respect to the planar core. All materials were also characterized by powder X-ray diffraction and thermogravimetric analysis.

The design of redox-active metal-organic frameworks and coordination networks (CNs), which exhibit metal- and/or ligand-centered redox activity, has recently received increased attention. In this study, the redox-active metalloligand (RML) [Me4N]3 fac-[CrIII(mp)3] ( 1) (mp=2-mercaptophenolato) was synthesized and characterized by single-crystal X-ray diffraction analysis, and its reversible ligand-centered one-electron oxidation was examined by cyclic voltammetry and spectroelectrochemical measurements. Since complex 1 contains O/S coordination sites in three directions, complexation with K+ ions led to the formation of the two-dimensional honeycomb sheet-structured [K3 fac-{CrIII(mp)3}(H2O)6] n ( 2⋅6 H2O), which is the first example of a redox-active CN constructed from a RML with o-disubstituted benzene ligands. Herein, we unambiguously demonstrate the ligand-centered redox activity of the RML within the CN 2⋅6 H2O in the solid state. [ABSTRACT FROM AUTHOR]

A comparative investigation of the coordination assemblies formed between Co(NCS)2 and two monotopic 4,2':6',4"-terpyridine (4,2':6',4"-tpy) ligands or two related ditopic ligands is reported. Crystals were grown by layering MeOH solutions of Co(NCS)2 over a CHCl3 or 1,2-C6H4Cl2 solution of the respective ligand at room temperature. With 4'-(2-methylpyrimidin-5-yl)-4,2':6',4"-terpyridine (6), the 1D-coordination polymer {[Co2(NCS)4(MeOH)4(6)2]2MeOH8H2O}n assembles with 6 coordinating only through the outer N-donors of the 4,2':6',4"-tpy unit; coordination by the MeOH solvent blocks two cobalt coordination sites preventing propagation in a higher-dimensional network. A combination of Co(NCS)2 and 1-(4,2':6',4"-terpyridin-4'-yl)ferrocene (7) leads to {[Co(NCS)2(7)2]4CHCl3}n which contains a (4,4) net; the 2D-sheets associate through α-stacking interactions between ferrocenyl and pyridyl units. A 3D-framework is achieved through use of the ditopic ligand 1,4-bis(npropoxy)-2,5-bis(4,2':6',4"-terpyridin-4'-yl)benzene (8) which acts as a 4-connecting node in {[Co(NCS)2(8)2]²C6H4Cl2}n; the combination of metal and ligand planar 4-connecting nodes results in a {65.8} cds net. For a comparison with the coordinating abilities of the previously reported 1,4-bis(noctoxy)-2,5-bis(4,2':6',4"-terpyridin-4'-yl)benzene (3), a more flexible analogue 9 was prepared. {[Co(NCS)2(9)]²CHCl3}n contains a (4,4) net defined by both metal and ligand planar 4-connecting nodes. The noctoxy tails of 9 protrude from each side of the (4,4) net and thread through adjacent sheets; the arene-attached noctoxy chains associate through a combination of van der Waals and C-H...π interactions. [ABSTRACT FROM AUTHOR]

A flexible thioether ligand, 1,3-bis(methylthiomethyl)benzene (L) has been employed to prepare supramolecular assemblies with silver salts of various anions such as NO 3 − , BF 4 − , PF 6 − and SbF 6 − . X-ray structural analysis reveals that even though the same metal ion (Ag + ) and ligand (L) were used to react under the same conditions, anions have played a critical role in driving the variation of metal–ligand binding modes as well as network topologies of the resultant coordination polymers. The reaction of L with silver nitrate resulted in a 2-D coordination network 1 , composed of metallomacrocycles bridged with NO 3 − ions. A 3-D framework 2 was observed when silver tetrafluoroborate was used. Although BF 4 − ions were not involved in coordinating with metal centers, the participation of water molecules led to a different metal–ligand binding mode and hence the formation of a network with higher dimension. The large, non-coordinating anion PF 6 − was found to be responsible for the assembly of a 2-D grid-like network 3 , in which interesting 4+4 metallocycles occupied with PF 6 − ions were disclosed. However, the presence of a larger anion analog, SbF 6 − simplified the network structure to form a 1-D helical chain ( 4 ) through the coordination of solvent molecules (CH 3 CN) with silver(I) centers. [ABSTRACT FROM AUTHOR]

Recent research has examined how the concept of institutional capacity relates to the ability of organisations to deliver industrial symbiosis, and in particular how that ability itself can develop over time. One approach to developing industrial symbiosis has been to build a network of local bodies to work together to this end. Terming such a body an industrial symbiosis coordination network, this study innovatively applies institutional capacity building theory in the context of a Chinese eco-industrial park. It examines how the coordination network developed the expertise to encourage local companies to engage in industrial symbiosis. This research consisted of a qualitative study, including participant observation, semi-structured interviews and document analysis to analyse the development of an industrial symbiosis coordination network in Tianjin Binhai New Area. It is found that the network increased institutional capacity for local IS development by promoting relational links across organisational divisions and governance levels, and by increasing various types of knowledge for coordinating IS. The concept of institutional capacity building is shown to have cross-cultural applicability. Reflections on this study indicate that local government can play a vital role in building and maintaining an IS coordination network in the Chinese context, but that other bodies are also needed to mobilise institutional capacity for IS development. [ABSTRACT FROM AUTHOR]

Catassembly is a new concept in molecular assembly that is analogous to catalysis in chemical synthesis. However, for most molecular-assembled processes, the catassembler contributions are rather inconspicuous due to the low activation barriers. As a result, few systems dealing with the catassembly are available until now. In this paper, we report that naphthalene diimide coordination networks are formed under the catassembly of lone-pair-bearing catassemblers (e.g., N, N-dimethylacetamide, N-methylpyrrolidin-2-one). During such molecular assembly, a stable transition state between the electron-deficient naphthalene diimide tectons and catassemblers via the less common lone pair-π interactions was observed, which is supposed to play the key role in the enhancement of coordination abilities of organic tectons and thus formation of the final coordination networks. [ABSTRACT FROM AUTHOR]

A series of isomorphic lanthanide coordination polymers [Ln(III)(MBP)(NO)(Br)·2CHO] [Ln=Eu, Tb, Er, Yb, and Gd; MBP= N,N′-methylene-bis(pyridin-4-one)] featuring polycatenated sql cationic network and incorporated bromide counter ion were prepared. Their visible and near-infrared (NIR) luminescence properties were characterized by steady-state excitation and emission spectra, as well as luminescence lifetimes and quantum yields. The D dodecahedron coordination geometry causes visible light excitations and strongly monochromatic emissions. The external heavy-atom environment induces remarkable enhancement on the NIR emissions. The sensitization processes are revealed by analyzing the electronic properties of MBP ligand. [ABSTRACT FROM AUTHOR]

A series of coordination networks constructed from divalent metal ions, N,N ′-di(3-pyridyl)adipoamide ( L ) and phenylenediacetate ligands, including [Co( L ) 0.5 (1,2-pda)(H 2 O)] n (1,2-H 2 pda = 1,2-phenylenediacetic acid), 1 , [Co( L )(1,4-pda)] n (1,4-H 2 pda = 1,4-phenylenediacetic acid), 2 , [Ni 2 ( L ) 2 (1,2-pda) 2 (H 2 O) 2 ·4.5H 2 O] n , 3 , [Ni( L )(1,4-pda)(H 2 O) 0.5 ·2.5H 2 O] n , 4 , [Zn( L ) 0.5 (1,2-pda)] n , 5 , [CdBr( L )(1,2-pda) 0.5 ] n , 6 , and [CdI( L )(1,2-pda) 0.5 ] n , 7 , have been synthesized by hydrothermal reactions and structurally characterized by single crystal X-ray diffraction. Complexes 1 , 2 and 5 adopt the (4 2 ,6 3 ,8)(4 2 ,6)-3,4L83, (4 2 ,6 7 ,8)(4 2 ,6)-3,5L2 and (4 2 ,6 3 ,8)(4 2 ,6)-3,4L83 topologies, respectively, while 3 and 4 show the (4 8 ,6 7 )-6T2 and (4 8 ,6 7 )- sqc26 topologies, respectively, and both 6 and 7 display the (4 12 ,6 3 )- pcu topology. The L ligands in 3 adopt three different conformations, while the pda 2− ligands in 5 adopts the rare cis -conformation and those in the other complexes exhibit the trans -conformation. Moreover, the pda 2− ligands in complexes 1 , 2 and 5 display the μ 3 bonding mode to afford the 2D layer structures, in contrast to those in the other complexes that show the μ 4 and/or μ 2 bonding modes to form the 3D frameworks. The conformations of the L ligands are subject to the changes of metal ions and pda 2− ligands, resulting in various types of structure for 1 – 7 . Temperature-dependent PXRD patterns of complexes 1 , 3 and 4 indicate that their structural transformations upon removal of the water molecules are irreversible. The emission spectra of 6 and 7 reveal that the lower electronegativity of the iodide relative to the bromide has a significant effect on the bathochromic shift. [ABSTRACT FROM AUTHOR]

The mononuclear complexes [Ru(L oPh ) 2 ](PF 6 ) 2 and fac -[Ru(L 3-Py ) 3 ](PF 6 ) 2 have been prepared which contain different types of pendant binding site. In [Ru(L oPh ) 2 ](PF 6 ) 2 , one ligand acts as a tetradentate chelate but the other is only bidentate such that there is one bidentate pyrazolyl-pyridine site pendant from the Ru(II) complex core. In fac -[Ru(L 3-Py ) 3 ](PF 6 ) 2 in contrast there are three monodentate 3-pyridyl units pendant from the same face of the Ru(II) core. Two [Ru(L oPh ) 2 ](PF 6 ) 2 units assemble around an Ag(I) ion to give trinuclear [{Ru(L oPh ) 2 } 2 Ag](PF 6 ) 5 in which the Ag(I) ion is four coordinate. In the solid state three of these associate into a triangular trimeric array via π-stacking and CH⋯F hydrogen-bonding interactions to give an assembly which contains two cup-shaped cavities either side of a central Ag 3 face and pointing in opposite directions; these cavities contain H-bonded hexafluorophosphate anions. In MeCN solution at high concentrations (11 mM), according to 1 H NMR DOSY measurements the trinuclear complex [{Ru(L oPh ) 2 } 2 Ag](PF 6 ) 5 remains intact but there is no evidence for further aggregation into the trimer. Two fac -[Ru(L 3-Py ) 3 ](PF 6 ) 2 units combine with two {Ag(NCMe)} + units and an additional Ag(I) ion to give a complex coordination network [{Ru(L 3-Py ) 3 } 2 {Ag(MeCN) 2 } 2 Ag](PF 6 ) 7 . In this structure two fac -[Ru(L 3-Py ) 3 ](PF 6 ) 2 and two {Ag(NCMe)} + units form tetranuclear Ru 2 Ag 2 rings via Ag–N(pyridyl) interactions; these rings are crosslinked into a one-dimensional chain by additional Ag–N(pyridyl) interactions. Argentophilic Ag⋯Ag interactions then connect the resulting chains into two-dimensional sheets. Both mixed-metal networks are based on initial formation of kinetically inert Ru(II) complexes which then associate in a separate step with Ag(I) ions, via pendant N-donor binding sites. However [{Ru(L oPh ) 2 } 2 Ag](PF 6 ) 5 exploits π–π stacking and hydrogen-bonding interactions to form in the solid state a trimeric assembly which encapsulates anions; in contrast [{Ru(L 3-Py ) 3 } 2 {Ag(MeCN) 2 } 2 Ag](PF 6 ) 7 exploits argentophilic interactions to complete formation of the network. [ABSTRACT FROM AUTHOR]

A series of 2-dimensional (4,4) nets formed in reactions of Co(NCS) 2 with divergent 4′-functionalized-4,2′:6′,4″-terpyridine ligands is reported, and the effects of the 4′-substituent R (ligand 1 , R = t Bu; 5 , R = MeO; 6 , R = EtO; 7 , R = n PrO) on the packing of the nets are described. The 2D-coordination networks in [{Co(NCS) 2 ( 6 ) 2 }·4CHCl 3 ] n and [{Co(NCS) 2 ( 7 ) 2 }·4CHCl 3 ] n are essentially isostructural. On going to [{Co 2 (NCS) 4 ( 5 ) 4 }·2CHCl 3 ·1.5MeOH] n , modification of both the geometry of the rhombuses that comprise the network, and the packing occurs. All three structures feature head-to-tail π-stacking of 4′-(4-alkoxyphenyl) units, but with variation in their relative orientations. In contrast, [{Co(NCS) 2 ( 1 ) 2 }·0.5H 2 O] n comprises double layers of (4,4) nets with hydrophobic coatings of tert -butyl groups, leading to alternating wide and close spacings between adjacent nets. [ABSTRACT FROM AUTHOR]