Potassium-promoted anionic selectivity of lanthanide bis(tetra-15-crown-phthalocyaninate) complexes

The interaction between neutral, lanthanide bis(tetra-15-crown-5-phthalocyaninate) complexes Ln[(15C5)₄Pc]₂⁰, (Ln = La, Tb, and Tm) and potassium bromide, picrate, or tetraphenylborate in chloro-form-acetonitrile solutions is studied using the spectrophotometric titration. The architecture of the supramolecular aggregates formed is shown to depend on the size of the lanthanide ion introduced into crown-phthalocyaninate and the nature of potassium salt anion.     

Supramolecular assembly of sandwich-type heteroleptic lanthanum (porphyrinato)(phthalocyaninates)

Concentration and cation-induced supramolecular assembly of heteroleptic double- and triple-decker [An₄P]La[(15C5)₄Pc] and [An₄P]La[(15C5)₄Pc]La[An₄P] lanthanum complexes (An₄P²⁻ = 5,10,15,20-tetra-(4-methoxyphenyl)-porphyrinate dianion and(15C5)₄Pc²⁻ = tetra-(15-crown-5)-phthalocyaninate dianion) is studied. Double-decker [An₄P]La[(15C5)₄Pc] complex is shown to be susceptible to effective concentration-driven assembly determined by the deviation from the Beer-Lambert-Bouguer law up to a concentration of 10⁻⁶ M. Triple-decker [An₄P]La[(15C5)₄Pc]La[An₄P] complex is not inclined to the concentration-driven assembly up to a concentration of 10⁻⁴ M. The interaction between the receptors and sodium or potassium salt is determined by the receptor structure and independent of the salt anion. When interacting with potassium salts, the double-decker complex can form a supramolecular cofacial dimer. In the case of the triple-decker complex, the crown-phthalocyanine deck of the molecule is sterically blocked, and supramolecular aggregates do not form. Sodium cations can be encapsulated in the crown ether rings of both receptors.     

New Hybrid Materials Based on Nanostructured Aluminum Oxyhydroxide and Terbium(III) Bis(Tetra-15-Crown-5-Phthalocyaninate)

A new method was developed for preparation of hybrid functional nanostructures through interaction between terbium complex with tetra-15-crown-5-phthalocyanine Tb[(15C₅)₄Pc]₂ and the surface of highly porous nanostructured aluminum oxyhydroxids (NAOs). It was shown that immobilization of phthalocyaninate on an NAO surface may be reversible upon a sorption from the solution in chloroform, and irreversable, when the adsorption occurred on the NAO surface that was chemically modified using methyltrimethoxysilane and annealed at the temperature ranging from 500 to 1100°С (NAOM). Nanostructure and chemical properties of the obtained hybrid nanomaterials were studied with the use of different methods: scanning electron microscopy, XRD, IR and diffuse reflectance spectroscopy. The sensor properties of the obtained Tb[(15C₅)₄Pc]₂//NAO and Tb[(15C₅)₄Pc]₂//NAOM hybrid nanostructures were studied when they interacted with ammonia and iodine vapors. It was shown that the phthalocyaninate complex on the NAO surface was liable to reduction, while the phthalocyaninate complex on the modified NAOM surface was liable to oxidation.     

Photorefractive and nonlinear optical properties of indium(III) tetra(15-crown-5)phthalocyaninate-based composites

Photoelectric, nonlinear optical, and photorefractive properties of hybrid composite materials based on polyvinylcarbazole (PVK) and indium(III) 2,3,9,10,16,17,23,24-tetra(15-crown-5)phthalocyaninate [(15C5)₄Pc]In(OH) are studied in detail. Field dependence of the quantum efficiency in a 7.8 μm-thick layer containing 5 at % [(15C5)₄Pc]In(OH) is measured. The best approximation of the quantum efficiency with Onsager’s equation corresponds to a quantum yield of thermalized electron-hole pairs φ₀ = 0.01 at initial separation r ₀ = 9.8 Å. Z-scan measurements in a nanosecond range showed that the electric susceptibility of [(15C5)₄Pc]In(OH) solution in tetrachloroethane (TCE) with a concentration of 7 × 10^?4 mol/L is χ⁽³⁾ = 1.34 × 10^?9 esu. The maximum coupling gain coefficient found for the material composed of PVK and 5 wt % [(15C5)₄Pc]In(OH) at an electric-field intensity of 200 V/μm is Γ = 80 cm^?1, and the difference between the coupling gain and absorption coefficients is Γ ? α = 70 cm^?1. The dependence of the coupling gain coefficient on the intensity ratio of interfering beams 1 and 2 (β = I ₁(0)/I ₂(0)) in a composite containing 3 wt % [(15C5)₄Pc]In(OH) is measured. An increase in β was attained by decreasing intensity of the signal beam I ₂(0) at constant intensity of the pump beam I ₁(0) = 0.15 W/cm² and E ₀ = 214 V/μm. Within the initial segment of the curve, the coupling gain coefficient increases from 30 to 60 cm^?1; then, the coefficient drops almost to the initial value. The data obtained show that the composite materials studied can be used in practice for correcting faded images. The combined analysis of the results obtained and similar data for gallium and ruthenium tetra-15-crown-5-phthalocyaninate complexes revealed the regularities in the change of the quantum yield of thermalized electron-hole pairs and the photorefractive coupling gain coefficient in a series of complexing metals: gallium(III), ruthenium(II), and indium(III). An increase in the molecular weight of the central metal atom is found to result in a substantial decrease in Γ and φ₀ due to the increase in the spin-orbit coupling constant.     

Solubilization of Crown-Substituted Magnesium Phthalocyaninates in Solutions of Salts of Bile Acids

Crown-containing Pc Mg[(B15C5O)₈Pc], Mg[(B15C5O)₄Pc], and Mg[(15C5)₄Pc] are in the monomolecular state in solutions of synthetic anionic surfactants: sodium dodecylsulfate and sodium dodecylbenzenesulfonate. In micellar solutions of bile-acid salts, molecular organization of crown-substituted Pc with different methods of introduction of crown groups into the macrocycle and their different numbers changes their state from predominantly monomeric for Mg[(B15C5O)₈Pc] in the presence of NaCl to the aggregated one in the case of Mg[(15C₅)₄Pc)]. Magnesium phthalocyaninate with annulated (15-crown-5)-fragments, Mg[(15C₅)₄Pc], is characterized by the highest sensitivity to the structure of the micelle-forming biocompatible surfactant.     

Magnesium Octa[(4'-Benzo-15-Crown-5)-Oxy]Phthalocyaninate in Low-Molecular Hydrogels: Spectral Properties and Release under Stimulation

This work is dedicated to low-molecular hydrogels based on biodegradable sodium deoxycholate (SDC) and lysine hydrochloride (lys × HCl) with magnesium octa-[(4'-benzo-15-crown-5)-oxy]phthalocyaninate (Mgcr₈Pc) as the active component, namely, their synthesis, spectral properties of gel-solubilized Mgcr₈Pc, its release from the gel etc. Addition of Mgcr₈Pc occurs both via the mixing of the components and via its diffusion from the aqueous solution into the phase of the formed SDC/lys × HCl gel. Mgcr₈Pc-containing hydrogels are thermoreversible. The state of Mgcr₈Pc in the SDC/lys × HCl/NaCl gel at the room temperature and in the melt is studied using spectral methods. Gel melting releases Mgcr₈Pc in the form of a micelle-bound monomer. The presence of the Mgcr₈Pc monomer phase in the phthalocyanine-carrying supramolecular hydrogel causes fluorescent activity of the latter.     

Magnesium octa[(4′-benzo-15-crown-5)oxy]phthalocyaninate in water micellar solutions of sodium deoxycholate

Aggregation of magnesium octa-[(4′-benzo-15-crown-5)oxy]phthalocyaninate (Mgcr₈Pc) in solutions of biocompatible anionic surfactant, sodium deoxycholate (SDC), was studied. It was shown using the electron absorption spectra that formation of Mgcr₈Pc monomers in micellar solutions of SDC is affected by both increased surfactant concentration and by changes in the ionic strength of solution after sodium chloride is added. The effect of the chemical structure of biocompatible anionic surfactant on monomerization of crown-containing phthalocyanines was identified; this fact opens new possibilities for using this family of compounds for fluorescent diagnosis and photodynamic therapy.     

The effect of aggregate state of octa-(benzo-15-crown-5)-substituted phthalocyanines in aqueous solutions on the structure of self-organized composites of ultrathin ion layers

The method of layer-by-layer (LbL) deposition from aqueous solutions was used to obtain electrostatic self–organized composites consisting of cationic fragments of octa-[(4′-benzo-15-crown-5)oxy]phthalocyaninates of metals (Mcr8Pc)/K⁺ and anionic fragments of sodium polystyrenesulfonate or 4,4′,4″,4?-[cobalt phthalocyaninate-2,(3),9,(10),16,(17),23,(24)-tetrayl-tetrakis(oxy)]-tetrabenzoic acid. The electronic absorption spectra of composite coatings indicate preservation of structures formed in aqueous solutions of Mcr₈Pc: coaxial associates, noncoaxial associates, and high-order aggregates. An increase in the content of noncoaxial associates and the possible presence of suspension particles in the composite are observed.     

Octa- and tetra-(benzo-15-crown-5)phthalocyanines in surfactant-containing solutions

The behavior of octa-(benzo-15-crown-5)phthalocyanine (H₂cr₈Pc), as well as cobalt octa- and tetra-(benzo-15-crown-5)phthalocyaninates (Cocr₈Pc and Cocr₄Pc), in aqueous solutions containing cationic or anionic surfactants, such as cetyl trimethylammonium bromide (CTAB), sodium carboxymethyl cellulose (Na-CMC), and sodium dodecyl sulfate (SDS), is studied using electronic spectroscopy. The presence of eight benzo-15-crown-5 ether fragments on the periphery of the phthalocyanine ring is shown to facilitate the dissolution of Pc in an aqueous environment. The interactions between CTAB and crown-containing Pc promotes the dissolution of H₂cr₈Pc; Cocr₈Pc; and, to a lesser degree, Cocr₄Pc, which is accompanied by the appearance of molecular aggregates, including heteronuclear cofacial dimers. The presence of a metal in the ring is not the necessary condition of the process. In microscopically heterogeneous medium, such as an aqueous SDS-containing solution, H₂cr₈Pc is present in monomeric form at SDS concentrations close to C _cr and in dimeric form at SDS content below C _cr. Under similar conditions (environment, surfactant), Cocr₄Pc can exist in monomeric form at SDS concentrations much high than C _cr. The effect of the size of cation on the form of the crown-containing Pc in an aqueous solution is illustrated by an example of H₂cr₈Pc. Na-CMC promotes the dissolution of Pc and enables one to produce K⁺/Mcr₈Pc-modified films from aqueous solutions.     

Physicochemical properties of solutions and ultrathin films of triple-decker gadolinium tetra-15-crown-5-phthalocyaninate

The ability of the triple-decker gadolinium complex with tetra-15-crown-5-phthalocyanine Gd₂(R₄Pc)₃, (R = 15-crown-5) (1) to form monolayers and Langmuir-Blodgett films (LBFs) was studied for the first time. The charge characteristics of molecules of a triple-decker phthalocyaninate in monolayer, as well as their orientation and adhesion to the water subphase, were controlled by changing the surface pressure, pH, and subphase composition (aqueous solutions containing triethylenetetramine (TETA) and metal cations). It was shown that the presence of Na⁺ and protonated TETA aminogroups in resulted in an increasing limiting monolayer area and significant decreasing of the monolayer liquid state region. It is proven that the observed effects are caused by the conformational and charge transitions of peripheral crown ethers induced by their interaction with cations. A comparison of the differential reflectance spectra of the complex monolayer on the deionized water surface with UV-Vis absorption spectra of three-layer Gd₂(R₄Pc)₃ LBF and complex solution in chloroform shows that partial complex oxidation and intensive stacking formation occurs already at the stage of monolayer formation on the subphase surface. Electrochemical studies of three-layer LBFs performed at the indium-tin-oxide electrodes (ITO-electrodes) using cyclic voltammetry (CV) showed three reversible redox waves in the potential range −200 to +1100 mV (vs. Ag⁺/AgCl). All registered peaks remain the same position and intensity upon multiple cycling. plasmon resonance (SPR) measurements allow to register three stable redox states of studied LBF upon applying the external potential. Such behavior shows the possibility to use multistep redox transformations of studied complex LBF for developing of stable and reproducible switchable optoelectronic systems.     

Radical cation salts of bis (ethylenediseleno) tetrathiafulvalene with halide mercurate anions

Four bis(ethylenediseleno) tetrathiafulvalene (BEDSe-TTF)-based salts, (BEDSe-TTF)₂Hg₂X₂ (X=I. Br), (BEDSe-TTF)₄Hg₃Br₈ · C₂H₃Cl₃ and (BEDSe-TTF)₄Hg₃Br₄ · 1.5C₂H₃Cl₃, have been prepared by electrocrystallization. Two of them. (BEDSe-TTF)₂Hg₂X₆, have been characterized by X-ray crystallography. The triclinic (space group Pī) room-temperature lattice parameters when X=I are: a = 6.798(4),b = 10.728(7), c 15.905(9) Å, α=106.33(6)°, ß=99.78(4)°, γ-92.97(5), V = 1090(1) ų. When X =Br the parameters are: a=6.665(3), b= 10.314(5), c=15.720(7) Å, α-105.70(4)°, ß=99.65(4)°, γ=93.79(4)°, V = 1018(1) ų. At room temperature, (BEDSe-TTF)₄Hg₃Br₈ · C₂H₃Cl₃ is metallic and the others are semiconductors.     

Tetra(9,10-phenanthro)tetraazaporphyrin - phthalocyanine: Comparative electrical conductivities

Tetra(9,10-phenanthro)tetraazaporphyrin, H₂TPTAP, has been synthesized and characterized for comparative electrical conductivity measurements with phthalocyanine, H₂Pc, before and after iodine doping. The objective is to determine the effect on conductivity of fusing eight additional benzo rings to the periphery of the phthalocyanine ring. H₂Pc doped to a (H₂Pc)I_2.5 composition with a resistivity decreases from 10¹⁵ to 1 ω cm, while H₂TPTAP doped to a (H₂TPTAP)I_0.26 composition with a corresponding resistivity change from 10¹¹ to 10⁸ ω cm. Experimental data and the literature indicate that benzene rings fused to the periphery of the tetraazaporphyrin ring have little π-electron interaction. Similarly, the structure-conductivity correlation of data is interpreted as indicating that fusion of additional benzo rings has an insulating substituent group effect on oxidation of and charge transport between the tetraazaporphyrin rings in the polycrystalline solid.     

Lanthanide complexes with acetylacetonate and 5,10,15,20-tetra[para-(4-flourobenzoyloxy)-meta-ethyloxy]phenylporphyrin

Lanthanide complexes of acetylacetonate and 5,10,15,20-tetra[para-(4-flourobenzoyloxy)-meta-ethyloxy]phenylporphyrin having the general formula Ln[(FBOEP)₄P]acac (where Ln=Ho, Er, Yb, Lu; FBOEP=[para-(4-flourobenzoyloxy)-meta-ethyloxy]phenyl; Hacac=acetylacetone; P=porphyrin) have been prepared and characterized. A structure is proposed in which one 5,10,15,20-tetra[para-(4-flourobenzoyloxy)-meta-ethyloxy]phenylporphyrin is coordinated to a rare earth ion in a tetradentate fashion, while one acetylacetonate is coordinated to the same metal ion in a bidentate fashion. We investigated the photo-generated charge behavior of the ligand and the complex, Lu[(FBOEP)₄P]acac, by means of surface photo-voltage spectroscopy (SPS) and field induced surface photo-voltage spectroscopy (FISPS) which are useful tools to investigate the photo-physics of excited states generated by absorption in the aggregate state.     

Characterization of potassium lithium niobate (KLN) ceramic system

The room temperature stability region of the tetragonal tungsten bronze-type potassium lithium niobate (K₃Li₂Nb₅O₁₅, KLN) has been determined by X-ray phase analysis on ceramic samples synthesized by solid state reaction in the composition range of [K₂O] = 28–33 mol%, [Li₂O] = 12.5–20.5 mol% and [Nb₂O₅] = 50.5–55.5 mol%. Lattice parameters and temperature dependence of the dielectric constants were measured on single phase samples. The axial a/c ratio of the cell parameters, the density and the Curie temperature of the ferroelectric samples have been found predominantly characteristic for the Nb₂O₅ content, varying progressively between 3.11–3.14, 4.431–4.596 g/cm³ and 492–460 °C, respectively. The results are discussed from the points of view of defect chemistry and phase stability. The concentration of intrinsic defects formed primarily by antisite Nb atoms at Li sites has been estimated on the basis of “alkali cation vacancy formation model”.     

Copper(I) coordination ability of the outer S-position isomer of EDT-DMT-TTF (D1): crystal structure of (D1)2Cu2Br4,2CH2Cl2; structural correlation with the (D1)2Cu2Br6 copper(II) salt

The (D1)₂Cu₂Br₄,2CH₂Cl₂ (1) and (D1)₂Cu₂Br₆ (2) radical cation salts, where D1 is the outer S-position isomer of ethylenedithiodimethylthiotetrathiafulvalene (EDT-DMT-TTF), have been synthesized and their X-ray crystal structures have been solved. The molecular structure of 1 is built up from (D1–Cu₂Br₄–D1) metal complexes. Each copper(I) atom is coordinated to a sulfur atom of the D1 disulfide bridge through a σ-type dative bond. Consequently, Cu₂Br₄ part is located between two organic molecules which are approximately plane and parallel to each other. In compound 2, (Cu₂Br₆)²⁻ anions, in which copper atoms are at the +2 oxidation state, also lie between two oxidized donors. In both resulting structures, the D1–Cu₂Br_x–D1 parts (x=4 for 1, x=6 for 2) are stacking in order to form columns containing dimerized (D1⁺)₂ units.     

Synthesis and luminescence properties of rare earth ternary complexes consisting of Tb(III), β-diketones and 1,10-phenanthroline (phen)

In order to study the luminescent properties of ternary rare earth complexes with β-diketone ligand, three new β-diketone ligands, 1-phenyl-3-(p-phenylethynylphenyl)-1,3-propanedione(HPPP), 1-(2-thienyl)-3-(p-phenylethynylphenyl)-1,3-propanedione (HTPP) and 1-(2-furyl)-3-(p-phenylethynylphenyl)-1,3-propanedione (HFPP), were synthesized by Sonogashira coupling reaction and Claisen condensation. Three new ternary rare earth complexes, TbL₃phen (L = PPP, TPP, or FPP), were synthesized by the reaction of rare earth chloride TbCl₃,1,10-phenanthroline (phen) with HPPP, HTPP, or HFPP respectively, in alcohol solution. The compositions were characterized by means of elemental analysis, chemical analysis, and IR spectra. Luminescent properties of the three new complexes have been studied. The results show that the ternary Tb(III) complexes only emit the weak fluorescence of the Tb(III) ion, which reveals the triplet state energy of the ligands does not match well with the excited state vibrating energy of Tb³⁺ ion.     

Synthesis,crystal structures and properties of new radical cation salts based on some tetrathiapentalene derivatives with halogenomercurate anions

New radical cation salts of BDH-TTP [2,5-bis(1,3-dithiolan-2-ylidene)-1,3,4,6-tetrathiapentalene], BDA-TTP [2,5-bis(1,3-dithian-2-ylidene)-1,3,4,6-tetrathiapentalene] and DTDH-TTP [2-(1,3-dithiol-2-ylidene)-5-(1,3-dithiolan-2-ylidene)-1,3,4,6-tetrathiapentalene] with halogenomercurate anions have been prepared. X-ray analysis at 120 K revealed the κ-type arrangement of conducting donor layers in (BDH-TTP)₄Hg₃Br₈ and (BDH-TTP)₄Hg₃Cl₈, and the β-type packing of donor layers in the (BDA-TTP)₄Hg₂Br₆, (BDA-TTP)₆Hg₄I_10.34 and (DTDH-TTP)₆Hg₃Br₉ radical cation salts. The crystals of κ-(BDH-TTP)₄Hg₃Br₈, κ-(BDH-TTP)₄Hg₃Cl₈ and β-(DTDH-TTP)₆Hg₃Br₉ behave as metals down to liquid helium temperatures, the resistivity of BDA-TTP salts shows semiconducting temperature dependence.     

Fluorescence and preparation of Sr2（P2O7）：Ce,Tb phosphate by co-precipitation method

The micron-sized Sr2（P2OT）：Ce,Tb green phosphors were prepared by being annealed at different temperatures with its precursors synthesized by co-pre-cipitates of （NH4）2HPO4 at ambient temperature. The phase structure, grain size, surface morphology, and luminescent properties of phosphors were investigated by X-ray diffraction, scanning electron microscope, trans-mission electron microscope, and fluorescence spectrum. The results show that the product of precursor annealed at 1,100 ℃ is Sr2（P2O7）：Ce,Tb, which belongs to ortho-rhombic phase. The powder is spherical and the size dis-tribution is in micron grade. The sample with the molar ratio of Sr/Tb/Ce of 100.0：0.4：0.6 shows the best fluores-cence effect annealed at 1,100 ℃ for 3 h. The phosphors produce green fluorescence by being excitated with ultra-violet radiation of 254 nm wavelength, and the main emission peak is at 547 nm. The Sr2（P2O7）：Ce,Tb phos-phors synthesized by co-precipitation method of precursors at ambient temperature is a kind of efficient green-emitting phosphors.     

Quantum chemical aided molecular design of ionic liquids as green electrolytes for electrodeposition of active metals

Quantum chemical calculation was used to estimate the reduction potentials of 25 organic cations and the oxidation potentials of 11 anions. This information was used to select promising cations and anions for the preparation of ionic liquids as green electrolytes for electrodeposition of active metals. The reasonable linear correlations between the lowest unoccupied molecular orbital (LUMO) energies and the reduction potentials of cations, and the linear relationships between the oxidation potentials and the highest occupied molecular orbital (HOMO) energies of anions were obtained. The orders of electrochemical stability for cations and anions being obtained agree well with the experimental measurements. The suitable ionic liquids with sufficiently wide electrochemical windows for electrodeposition of active metals are suggested to be [Emim]NTf₂, [Bmim]NTf₂, [Bmim]BF₄, [Bmim]PF₆, [Bmim]CTf₃, [Emim]BF₄, [Emim]PF₆, [Emim]CTf_3..     

Synthesis and properties of μ-cyano(phthalocyaninato)-rhodium(III)

This contribution reports on the synthesis of μ-cyano(phthalocyaninato)rhodium(III), [PcRhCN]_n (1), by splitting off potassium cyanide from potassium(dicyano)phthalocyaninatorhodium(III), K[PcRh(CN)₂] (2). Monomeric complexes, PcRh(L)CN (7), were formed when [PcRhCN]_n (1) was treated with base molecules L, such as n-butylamine and pyridine. All compounds were characterized by IR, far-IR spectroscopy, thermal and elemental analyses, and partly by UV, ¹H-NMR and FD (field desorption) mass spectroscopy. The undoped polymer [PcRhCN]_n (1) exhibits a d.c. dark conductivity of 4 × 10^?4 S/cm, which was diminished by eight orders of magnitude when the polymeric structure was decomposed by treatment with a competing ligand.