Ag Interactions Research Articles

Supramolecular Assembly of Ag(I) Centers: Diverse Topologies Directed by Anionic Interactions.

Ag(I)–Ag(I) interactions in supramolecular structures have been achieved through the use of structural support from the ligand frames. In structures involving simple ligands like pyridine, strong π–π interaction leads to spatial ordering of the individual [Ag(L)2]+ units. In such structures anions also play a crucial role in dictating the final arrangement of the [Ag(L)2]+ synthons. In order to determine whether the anions can solely dictate the arrangement of the [Ag(L)2]+ synthons in the supramolecular structure, four Ag(I) complexes of 4-pyridylcarbinol (PyOH), namely, [Ag(PyOH)2]X (X = NO3– (1), BF4– (2), CF3SO3– (3), and ClO4– (4)) have been synthesized and structurally characterized. Gradual transformation of the extended structures observed in 1–3 eventually merges into a unique linear alignment of the [Ag(PyOH)2]+ units in 4 along the c axis, a feature that results in strong argentophilic interactions. Complex 4 is sensitive to light and is inherently less stable than the other three analogues. The structural variations in this set of extended assemblies are solely dictated by the anions, since π–π interaction between the substituted pyridine ligands is significantly diminished due to disposition of the −CH2OH substituent at the 4 position and H-bonding throughout the structure.

Use of thio and seleno germanones as ligands: silver(I) halide complexes with Ge═E→Ag-I (E = S, Se) moieties and chalcogen-dependent argentophilic interaction.

The potential of thio and seleno germanones [LPhGe═E] (L = aminotroponiminate (ATI) ligand, E = S 3, Se 4) to function as ligands has been demonstrated through the isolation of their silver(I) iodide complexes [{(t-Bu)2ATIGe(E)Ph}2(Ag2I2)] (E = S 5, Se 6) with a planar and discrete Ag2I2 core. Compounds 5 and 6 possess the hitherto unknown Ge═E→Ag-I moieties and the crystallographic data reveals the presence of a strong argentophilic interaction (2.950(1) Å) in complex 6, but is inconclusive in complex 5 (3.470(1) Å). Using theoretical studies, proof for the presence and absence of argentophilic interactions in complexes 6 and 5 was obtained, respectively. Further, it is disclosed that the donor ability of the chalcogen atoms in the Ge═E→Ag-I moieties dictate the Ag···Ag interaction in these complexes.

Design, Synthesis, and Photoluminescence Properties of One-, Two-, and Three-Dimensional Coordination Polymers: Anion-Assisted Argentophillic Interactions as Building Blocks

Five new Ag(I) complexes of the formulae {[Ag2(L1)2(NDS)]3H2O}n (1), {[Ag2(L2)2(NDS)]·2H2O}n (2), {[Ag3(L2)2(IQS)2]·(NO3)·4H2O·2MeOH}n (3), {[Ag2(L3)2(NDS)]·4H2O}n (4), and {[Ag2(L3)2(IQS)]·(NO3)·H2O}n (5) (L1 = 2,5-bis-pyridine-3-ylmethylene-cyclopentanone, L2 = 2,5-bis-pyridine-3-ylmethylene-cyclohexanone, L3 = 2,5-bis-pyridine-4-ylmethylene-cyclopentanone, NDS = naphthalene disulfonate, and IQS = isoquinoline-5-sulfonate) have been synthesized and characterized by elemental analysis, IR, powder X-ray diffraction, and single-crystal X-ray diffraction. Complexes 1–3 were found to have sulfonate supported Ag···Ag interaction, and the sulfonate ions act as linkers to form higher dimensional networks (ladder, two- and three-dimensional networks). The complexes 4 and 5, which contain 4-pyridyl substitution, do not form such Ag···Ag interactions, indicating a clear tendency of 3-pyridyl derivatives to promote such interactions over 4-pyridyl derivatives. This observation was also evidenced by the analysis of Ag(I) complexes in Cambridge Structural Database. Further, complexes 1–5 were found to exhibit solid-state photoluminescence in the green region at room temperature.

Selective Thermal Elongation of Metal–Metal Distances in the Two-Dimensional Assembly of Ag(I) Ions Templated by Assembled Peptide Ligands

To develop a tunable assembly of metal ions, we demonstrated a two-dimensional Ag(I) array in the crystalline state by using an assembly of dipeptide ligands as a template. The two-dimensional assembly of Ag(I) ions was obtained through the assembly of a Ag(I)-peptide polymer complex, which was held together by hydrogen bonding interactions. At –180 °C, one-dimensional zigzag chains of Ag(I) ions were formed in each layer, which further assembled to form two-dimensional layers. The arrangement of the Ag(I) ions included several Ag–Ag distances that are supported differently by the peptide assembly. Because of this difference, when heated from –180 to 50 °C, the Ag(I) layer displays anisotropic thermal expansion in the arrangements, in which one of the Ag–Ag distances selectively elongated. This expansion is reversible, allowing switching between the zigzag chain assembly and the Ag(I) dimer assembly. Moreover, the resulting crystalline Ag(I) complexes show luminescence at both room temperature and at –196 °C, suggesting the existence of Ag–Ag interactions.

One- and three-dimensional silver(I)-5-sulfosalicylate coordination polymers having ligand-supported and unsupported argentophilic interactions

Four new coordination polymers, namely, {Hemim·[Ag(Hssa)(H2O)]}n (1), {[Ag(ina)2 Ag(Hssa)]·CH3OH·H2O}n (2), {[Ag2(Hssa)(dmp)1.5]·2H2O}n (3) and [Ag2(Hssa)(daoc)]n (4) (Hssa: 5-Sulfosalicylate, emim: 2-ethyl-4-methylimidazole, ina: isonicotinamide, dmp: 2,5-dimethylpyrazine and daoc: 1,8-diaminooctane) were synthesized and characterized by IR spectroscopy, elemental analysis, single crystal X-ray diffraction, powder X-ray diffraction (PXRD) and thermal analysis techniques. Complexes 1 and 2 are one-dimensional (1D) coordination polymers while complexes 3 and 4 are three-dimensional (3D) coordination polymers. Complex 3 consists of three dimensional (3D) 3,3,6-c net with 3,3,6T37 topology. Complex 4 exhibits a 2-fold interpenetrating 3D framework with tfc topology. Complexes 1–4 contain ligand-supported (1–3) and unsupported (4) argentophilic Ag⋯Ag interactions. Photoluminescence spectra of the complexes demonstrate that photoluminescent properties may be attributed to intraligand transition of coordinated Hssa ligand.

Synthesis of silver nanoparticles on surface-functionalized multi-walled carbon nanotubes by ultraviolet initiated photo-reduction method

In this article, we described a new, facile method on fabrication of multi-walled carbon nanotubes (MWNTs) with silver nanoparticles by an ultraviolet initiated method. MWNTs were functionalized with acrylic acid to introduce carboxylic acid groups, and then the Ag nanoparticles were synthesized on the functionalized MWNTs by using of ultraviolet irradiation without adding of any protective or reductive agent. The obtained MWNTs/Ag composites were analyzed with Fourier transform infrared spectrometer (FT-IR) spectroscopy, transmission electron microscope (TEM), X-ray powder diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). It was confirmed that Ag nanoparticles with diameters in a region of 5–10nm were anchored on the surface of MWNTs by an interaction of Ag and oxygen in the carboxyl group.

Influence of Ag+ interaction on 1D droplet array spacing and the repulsive forces between stimuli-responsive nanoemulsion droplets.

This paper reports results on the effect of interaction of Ag(+) on 1D droplet array spacing and the repulsive forces between stimuli-responsive nanoemulsion droplets, stabilized with an anionic surfactant--sodium dodecyl sulfate--and a diblock polymer--poly(vinyl alcohol)-vinyl acetate. The repulsive interaction is probed by measuring the in-situ equilibrium force-distance in the presence of Ag(+) using the magnetic chaining technique. At a constant static magnetic field, emulsion droplets form 1D array that diffract visible light. A large blue-shift in the diffracted light is observed in the presence of interacting Ag(+) because of the reduction in the interdroplet spacing within the 1D array. The in-situ equilibrium force-distance measurement results show that the onset of repulsions and magnitude of repulsive forces are strongly influenced by the presence of Ag(+) in ppb levels. This suggests that the Ag(+) ions screen the surface charges through the formation of both Stern and diffuse electric double layer and produces a dramatic blue-shift in surfactant-stabilized emulsion, whereas a dramatic conformational change in the adsorbed polymer layer causes a reduction in the 1D array spacing in the diblock polymer stabilized emulsion. The force-distance results are compared with the predictions of electrical double-layer and repulsive steric forces. The droplet array shows an excellent selectivity to Ag(+) due to the strong interaction of Ag(+) with the stabilizing moieties at the oil-water interface. The possible mechanisms of interaction of Ag(+) with surfactant and polymer are discussed. The dramatic decrease in the 1D array spacing in the presence of Ag(+) may find promising practical applications in the development of optical sensors for selective detection of cations with ultrahigh sensitivity.

XPS and DFT studies of the electronic structures of AgAuS and Ag3AuS2

X-ray photoelectron spectra of core levels and the valence bands were acquired, and the density-of-states (DOS) were calculated using periodic density functional theory (DFT) for synthetic ternary compounds AgAuS and Ag3AuS2, known as minerals petrovskaite uytenbogaardtite, respectively, for the first time. The chemical shift of the Au 4f binding energy as large as 0.65eV relative to bulk elemental gold was found for Ag3AuS2, in contrast to only about 0.3eV for AgAuS. The DFT analysis showed, in particular, that the S 3p states are largely pushed out from the Ag 4d and Au 5d bands affording two sub-bands in the valence region of both substances, but the overlapping of the S 3p and Au 5d states is larger for Ag3AuS2. It was demonstrated that the energy position of Au 4f levels is mainly influenced by Au–Ag interaction, and increasing the number of Ag atoms in the first coordination shell of S–Au–S units on going from AgAuS to Ag3AuS2 results in the positive shift of the Au 4f bands consistent with the experimental data.

Direct observation of the excited state structure of a Ag(I)-Cu(I) complex

Heterodentate coordination complexes have been extensively studied because of their rich electronic and luminescent properties, which are of importance in the design of molecular devices. The short metal-metal contacts found in such complexes determine the nature of the lowest lying emissive states, and must be explored in order to understand their physical properties. Recent advances in time-resolved (TR) synchrotron techniques supported by specific data collection strategies and data processing procedures [1] allow for elucidation of molecular excited state geometries in the solid state. The approach has been so far successfully applied to several high-quality Laue-data sets collected at the 14-ID BioCars beamline at the Advanced Photon Source.[2] In this contribution we present synchrotron TR experiment results obtained for a new solvent-free crystal form of a model complex containing Ag(I) and Cu(I) (Ag2Cu2L4, L = 2-diphenylphosphino-3-methylindole).[3] This system exhibits red solid-state luminescence with a lifetime of about 1 µs. This is one of the shortest-lived excited states we have studied so far with the Laue technique. The relatively short lifetime goes along with significant structural changes observed upon irradiation, such as, the Ag...Ag distance shortening of about 0.2 Å in the excited state. The results clearly show strengthening of the Ag...Ag interactions suggesting a bond formation upon excitation. The photocrystallographic findings are supported by spectroscopic measurements and quantum computations. The results confirm the triplet nature of the emissive state originating mainly from a ligand-to-metal charge transfer. Research funded by the NSF (CHE1213223). BioCARS Sector 14 is supported by NIH, National Center for Research Resources (RR007707). APS is funded by the U.S. DOE, Office of Basic Energy Sciences (W-31-109-ENG-38). KNJ is supported by the Polish Ministry of Science and Higher Education through the "Mobility Plus" program.

Fate of engineered nanomaterials in surface water: Factors affecting interactions of Ag and CeO2 nanoparticles with (re)suspended sediments

Engineered nanoparticles (NPs) are increasingly being utilized in numerous commercial applications, thereby augmenting the likelihood that they will find their way into aquatic or terrestrial environments, where their fate and behaviour still are not yet fully understood. The main objective of this study was to examine the fate of Ag and CeO2 NPs in sediment suspensions. Particularly, the association of these nanoparticles and their corresponding ions with sediment constituents was studied. Four different intertidal sediments were sampled along the river Scheldt (Belgium), dried, ground, and thoroughly characterized, before being re-suspended with Milli-Q water. The suspensions were spiked with nanoparticles or ions, continuously shaken for 24h, and subjected to gravitational settling or centrifugation, where after the remaining silver or cerium concentration in the supernatants were determined via ICP-OES. It was shown that centrifugation speed significantly affects the amount of suspended material and the TOC content in the liquid phase. In the absence of sediment, Ag and CeO2 NPs as well as their corresponding ions were unaffected by centrifugation speed over a 24-h time period, whereas significant differences were observed in the presence of sediment, indicating that sediment properties influence the partitioning behaviour of the nanoparticles. The amount of silver or cerium remaining in suspension was positively correlated with the TOC and suspended matter content, suggesting interactions of the nanoparticles with sediment colloidal matter. Remarkably, Ag and CeO2 NPs appear to bind less strongly to sediment constituents in comparison to their ionic counterparts, rendering the nanoparticles more mobile.

Syntheses, structures and luminescence of silver(I) sulfonate complexes with nitrogen-containing ligands

In this paper, three new Ag(I) coordination compounds, namely, AgL(3-iso)2 (1), [Ag4L4(bipy)4]·bipy·CH3CN·6H2O (2) and [Ag10L8(hmt)10(H2O)4]·(L)2·15H2O (3) (where 3-iso=3-methylisoquinoline, bipy=4,4′-bipyridine, hmt=hexamethylenetetramine and L=4-chloro-benzenesulfonate anion), have been synthesized by varying the nitrogen-containing secondary ligands. In compound 1, Ag(I) atoms are coordinated by 3-iso ligands and L anion to generate a discrete molecular structure. For compound 2, when the 3-iso ligand was replaced by bipy, Ag(I) atoms of 2 are linked by bipy ligands to generate a 1D polymeric chain, which are further expanded to a double chain through Ag⋯Ag interaction. In 3, the hmt ligands connect Ag(I) atoms to give a undulate 2D layer. These results indicate that the nitrogen-containing secondary ligands play important roles in the structural formation of the Ag(I) complexes. Moreover, the luminescent properties, elemental analyses and IR spectroscopy of these compounds were also studied.

A DFT investigation of the interactions of Pd, Ag, Sn, and Cs with silicon carbide

With a view to understand the diffusion of radionuclides through the silicon carbide layers in tristructural isotropic coated fuel particles, density functional theory calculations are applied to assess the interaction of palladium, silver, tin, and caesium with silicon carbide. The silicon carbide molecule (Si2C2), crystalline cubic silicon carbide (β‐SiC), and the (120) ∑5 grain boundary of β‐SiC are investigated to elucidate the differences in the interactions of silicon carbide with these elements. The main stabilizing forces in the PdSi2C2 complex were found to be donor‐acceptor charge transfer (covalent) interactions, the Ag and Sn complexes involve significant contributions from both electrostatic and covalent interactions, while the Cs atom is bonded dominantly by electrostatic forces. For the unconstrained MSi2C2 model, the following energetic ordering was obtained: Pd > Sn > Cs > Ag. The steric constraints in the bulk SiC and on the grain boundary change the order of binding energies to Pd > Ag > Sn > Cs in the interstitials and Pd > Sn > Ag > Cs in vacancies and at the grain boundary. By comparing the incorporation energies in the solid phases, it is possible to group these elements by similarities in the patterns of incorporation energies. Silver and palladium form a group with carbon, tin is grouped with silicon, and caesium is on its own. © 2014 European Commission. International Journal of Quantum Chemistry published by Wiley Periodicals, Inc.

Bimetallic AgCu/SBA-15 System: The Effect of Metal Loading and Treatment of Catalyst on Surface Properties

Monometallic (Ag, Cu) and bimetallic (Ag + Cu) catalysts were prepared by metal loading (Ag:Cu = 0.3 and 1.8) on 3-aminopropyl-trimethoxysilane-grafted SBA-15 and calcination at 773 K and either reduction by NaBH4 before calcination or activation in inert gas after calcination. The catalysts treated in this way were fully characterized. Cu/SBA-15 samples contained CuO and oligonuclear [Cuδ+···Oδ−···Cuδ+]n clusters irrespective of the catalyst treatment. Silver–SBA-15 contained cationic silver in the form of Ag2O which was transformed to metallic Au0 by the reduction with NaBH4 and was not reoxidized during calcination. In bimetallic catalysts, different species were identified depending mainly on the Ag:Cu atomic ratio and the post modification treatment. When the excess of copper was applied the core (Ag2O)–shell (CuO) structure of the bimetallic phase was formed. If the reduction with NaBH4 was used prior to calcination, the same core–shell structure was present but with higher dispersion of CuO, manifested as a higher basicity of the catalysts revealed as a higher selectivity to acetone in 2-propanol dehydrogenation and to CO2 in methanol oxidation. The use of silver in excess led to the presence of both cationic silver and copper species in calcined AgCu(1)/S(C) material. In the sample reduced with NaBH4 and then calcined (AgCu(1)/S(RC)), metallic copper was partially surrounded by metallic silver. In bimetallic samples Cu–Ag interaction led to the electron transfer from copper to silver species enhancing their redox properties and causing the superior activity in the low-temperature total oxidation of methanol to CO2.

Adsorption Properties of Two-Dimensional NaCl: A Density Functional Theory Study of the Interaction of Co, Ag, and Au Atoms with NaCl/Au(111) Ultrathin Films

Recent experiments have shown that Co atoms deposited on NaCl/Au(111) ultrathin films give rise to spontaneous substitutional doping of the NaCl layer (Li et al. Phys. Rev. Lett. 2014, 112, 026102 ). In this work, the interaction of Co atoms deposited on NaCl/Au(111) films is investigated by means of density functional theory calculations. Co atoms have been adsorbed on various sites of the surface of unsupported and supported two- and three-layer NaCl films; incorporation of the Co atoms in interstitial positions or replacement of Na and Cl lattice ions has also been investigated. The Co adsorption properties are compared with those of Ag and Au atoms. We found that all metal atoms interact strongly with NaCl/Au(111) films, giving rise to large structural distortions of the insulating layer. Co, Ag, or Au incorporation in interstitial positions between the first and second NaCl layers is thermodynamically preferred over adsorption on surface sites. The results show the reactivity of NaCl with Co is highe...

Three coordination polymers of transition metals built using HPPC ligand: Crystal structures and novel topology

A new pyrazole-carboxylate type ligand, 3-(pyridin-3-yl)-1H-pyrazole-5-carboxylic acid (HPPC) was prepared from 3-acetylpyridine, diethyl oxalate and hydrazine hydrate. By employing this ligand, three new coordination complexes were prepared under solvothermal conditions: {[Ni(PPC)2]·3H2O}n (1), [Ag(PPC)]n (2) and [Cd(PPC)Cl]n (3). Single-crystal X-ray diffraction analyses reveal that 1–3 exhibit three different structural types. Complex 1 displays a 4-connected net with the Schläfli symbol (44·62) topology, several types of hydrogen bonds connect the 2-D layer to a 3-D structure. Complex 2 is built from [Ag(N2O)] clusters and PPC ligand as 3-connected linker with Schläfli symbol {36·46·53} without consideration of Ag⋯Ag interaction. The 2-D networks are also linked to form 3 D framework via Ag⋯Ag interaction. Complex 3 can be regarded as a (3, 3)-connected net with the Schläfli symbol {333·433}, which consists of [Cd(N2O2)] clusters and PPC ligand as 3-connected bridge. The layers are further linked by the cholride atoms to generate a 3-D network.

Improvement of transparent silver thin film anodes for organic solar cells with a decreased percolation threshold of silver

Organic solar cells (OSCs) using thermally evaporated Ag thin films as the transparent anode are investigated with poly(3-hexylthiophene) (P3HT) and [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) films as the active layer. The optimal power conversion efficiency (PCE) of 2.57% is obtained for the device with the 11nm thick Ag layer, namely the percolation threshold of Ag. Then an interlayer of MoO3 between the Ag anode and glass substrate is introduced. Two different thicknesses of MoO3 (2nm or 10nm) are chosen here, corresponding to the unclosed or closed MoO3 layer, respectively. It is observed that the introduction of the MoO3 interlayer can effectively improve the wetting of Ag on the substrate and reduce the percolation threshold of Ag. When the MoO3 thickness is 10nm, since the surface energy of Ag (γ=1.25Jm−2) is higher than that of MoO3 (γ=0.06Jm−2), the Ag–Ag interactions are stronger than the Ag-substrate interactions, weakening the surface-modifying effect. In contrast, since the 2nm thick unclosed MoO3 layer may create preferred nucleation sites on the substrate to enhance the lateral growth of Ag film effectively, a very low sheet resistance of 9.32 Ω/□ and a relatively high transmittance are obtained for MoO3 (2 nm)/Ag (9 nm) anode. The PCE of corresponding OSCs can be improved to 2.71%, comparable to that of ITO-based reference OSCs (PCE of 2.85%). From our results, it is concluded that the performance of the Ag thin film electrode can be improved by decreasing the percolation threshold of Ag with a MoO3 interlayer (especially when the MoO3 layer is thin). It may be instructive for the further research of metal thin film electrodes.

Novel networks of silver(I) cations assembled with 2,3-pyridinedicarboxylic acid: From 2D sheet to 3D network

Two novel [Ag2pyd]n (1) and [Ag4(apyz)3 (pyd)2·3H2O]n (2) supramolecular frameworks constructed by H2pyd (2,3-pyridinedicarboxylic acid) were synthesized and characterized by X-ray single crystal diffraction, elemental analyses and IR spectra. The pyd building block was extended into well-ordered supramolecular frameworks by AgO and Ag···Ag interaction. Ligand-supported weak argentophilic interactions are observed in compounds 1 and 2, but novel 1D Ag···Ag silver-wire structure is only in 1. The linkers of pyd and apyz (aminopyrazine) play an important role in the self-assembly process. The combination of pyd ligands and Ag ions generate a 2D layer structure in complex 1 and pyd ligands adopt different coordination modes to connect Ag atoms to form 3D supramolecular framework in complex 2. Comparing the experimental results, it is clear that the apyz ligand plays a crucial role in the formation of the resulting structures. The results are reported in this article.

Synthesis and characterization of silver(I) pyrazolylmethylpyridine complexes and their implementation as metallic silver thin film precursors.

A series of light- and air-stable silver(I) pyrazolylmethylpyridine complexes [Ag(L(R))]n(BF4)n (L = pyrazolylmethylpyridine; R = H, 1; R = Me, 2; R = i-Pr, 3) and [Ag(L(R))(NO3)]2 (L = pyrazolylmethylpyridine; R = H, 4; R = Me, 5; R = i-Pr, 6) has been synthesized and structurally and spectroscopically characterized. In all of the molecular structures, the pyrazolylmethylpyridine ligands bridge two metal centers, thus giving rise to dinuclear (2, 4, 5, and 6) or polynuclear structures (1 and 3). The role played by the counteranions is also of relevance, because dimeric structures are invariably obtained with NO3(-) (4, 5, and 6), whereas the less-coordinating BF4(-) counteranion affords polymeric structures (1 and 3). Also, through atoms-in-molecules (AIM) analysis of the electron density, an argentophilic Ag···Ag interaction is found in complexes 2 and 4. Thermogravimetric analysis (TGA) shows that the thermolytic properties of the present complexes can be significantly modified by altering the ligand structure and counteranion. These complexes were further investigated as thin silver film precursors by spin-coating solutions, followed by annealing at 310 °C on 52100 steel substrates. The resulting polycrystalline cubic-phase Ag films of ∼55 nm thickness exhibit low levels of extraneous element contamination by X-ray photoelectron spectroscopy (XPS). Atomic force microscopy (AFM) and scanning electron microscopy (SEM) indicate that film growth proceeds primarily via an island growth (Volmer-Weber) mechanism. Complex 4 was also evaluated as a lubricant additive in ball-on-disk tribological tests. The results of the friction evaluation and wear measurements indicate a significant reduction in wear (∼ 88%) at optimized Ag complex concentrations with little change in friction. The enhanced wear performance is attributed to facile shearing of Ag metal in the contact region, resulting from thermolysis of the silver complexes, and is confirmed by energy-dispersive X-ray analysis of the resulting wear scars.

Silver(I)/Bipyrazole/Dicarboxylate Interpenetrated Coordination Networks: Spontaneous Chiral Resolution, Modulation of Topologies, Water Clusters, and Photoluminescences

Seven novel silver(I) coordination networks with mixed flexible 3,3′,5,5′-tetramethyl-4,4′-bipyrazole (bpz) and C3–C9 aliphatic dicarboxylic acids, [Ag2(bpz)4(mal)·7H2O]n (1L and 1R), [Ag2(bpz)3(suc)]n (2), [Ag4(bpz)5(glu)2]n (3), [Ag4(bpz)5(adip)2]n (4), [Ag4(bpz)7(pim)2·12H2O]n (5), [Ag2(bpz)4(sub)·7H2O]n (6), and [Ag2(bpz)3(aze)·3.5H2O]n (7) (H2mal = malonic acid, H2suc = succinic acid, H2glu = glutaric acid, H2adip = adipic acid, H2pim = pimelic acid, H2sub = suberic acid, H2aze = azelaic acid), have been synthesized and structurally characterized by single-crystal X-ray diffraction analyses and further characterized by infrared spectra (IR), elemental analyses, powder X-ray diffraction (PXRD), and thermogravimetric analyses (TGA). Single crystal X-ray diffraction analysis reveals that 1 crystallized into a pair of enantiomerically pure 3D 3-fold interpenetrated chiral SrSi2 networks (point symbol {103}) through spontaneous resolution in the absence of any chiral source. Complex 2 is a 3D 2-fold interpenetrated 3-connected uninodal dia-f network (point symbol {4·142}) without consideration of Ag···Ag interaction. Complexes 3 and 4 are similar 2D + 2D → 2D 63-hcb layer featuring 3-fold parallel interpenetration. Complex 5 is a 3D 3-fold interpenetrated 3,4-connected 3,4T1 network (point symbol {4·6·8}{4·62·83}). Complexes 6 and 7 are similar 2D + 2D → 2D fes layers (point symbol {4·82}) featuring 3-fold parallel interpenetration. In 1–7, structural diversity ranging from 2D hcb and fes layers to 3D chiral SrSi2, achiral dia-f, and 3,4T1 networks is modulated by dicarboxylates with alkyl chains of different lengths. Interestingly, a well-resolved octanuclear water cluster built from a chairlike (H2O)6 cluster and two water molecules dangling on two corners of it and a unusual seesaw-like pentanuclear water cluster is observed in the voids of 5 and 7, respectively. Furthermore, the solid-state photoluminescence properties of the 1–7 were investigated at 298 and 77 K.

Interaction of Ag(5s) and Ag(5p) with noble gas atoms

We investigate the interaction of ground and excited states of silver atom with all the noble gases, including helium. Born-Oppenheimer potential energy curves are calculated with quantum chemical techniques and spin-orbit effects in the excited states are included. We compare with experimentally available spectroscopic data, as well as previous calculations. The assignment of vibrational levels in the one experiment we compare with, may have to shift up by one unit.