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Coordination compounds of lanthanides attract increasing attention of researchers due to their unique physical and chemical properties, including interesting optical and magnetic behavior. Fine tuning of properties of functional materials based on them is possible by controlling the structure of complexes. This review describes the approach of applying NMR spectroscopy to solve the challenging problem of identification of paramagnetic lanthanide complexes, as well as to establish a correlation between the structure of the coordination sphere of lanthanide ions and the magnetic characteristics of the complexes. It has been shown how the analysis of lanthanide-induced shifts (LIS) and lanthanide-induced relaxation (LIR) in series of isostructural compounds contributes to the identification of spectral–structural correlations, which, in combination with X-ray diffraction and quantum-chemical data, make it possible not only to establish the structure of the compound in solution, but also to perform a primary assessment of the possibility of using lanthanides complexes as single molecule magnets.

An approach to immobilization of heterocycle-appended porphyrins bearing one or two anchoring groups at the surface of UiO-66 and UiO-67 MOFs has been developed. For this purpose, carboxy-substituted porphyrin’s derivatives Ni-4 and Ni-5 have been synthesized for the first time. It has been shown that the presence of one anchoring carboxy group at the periphery of the porphyrin is insufficient for the efficient immobilization. At the same time, the prepared pyrazinoporphyrin bearing two carboxy groups is efficiently immobilized at the surface of the MOF particles in 1 : 16 ratio with respect to hexanuclear Zr(IV) node clusters. The post-synthetic modification has been found to be the most efficient approach to prepare the target hybrid materials. The prepared materials are completely characterized by means of powder X-ray diffraction, scanning electron microscopy, and UV-vis diffuse reflectance and IR spectroscopies.

The review is concerned with studies on peculiar features of supramolecular organization of phthalocyanines (Pc) bearing complex-forming substituents (15-crown-5, 2-oxyphenylphosphonic acid residues) in organized aqueous microheterogeneous media based on cationic and anionic surfactants, bile salts (BS) including sodium deoxycholate (SDC), as well as polyelectrolytes and amphiphilic polymers including a phosphate buffer (pH 7.4). Organized, SDC-based fluorescence-active phthalocyanine-containing hydrogels obtained for the first time are also considered. In vitro accumulation and localization of Pc in human cervical adenocarcinoma cells, HeLa, as well as the photochemical and sensitizing properties of Pc including light cytotoxicity and photoinduced generation of reactive oxygen species were demonstrated taking octa-crown-substituted magnesium phthalocyaninate as an example.

The cation-induced dimerization of tetra-(15-crown-5)-substituted Al(III) phthalocyaninate with Na+, K+ and Rb+ salts in solution has been studied by 1H NMR. It has been demonstrated that two types of supramolecular dimers coexist in solutions, which is consistent with the existence of both the monomeric and oxygen-bridged dimeric forms of the initial Al(III) complex. With the use of mass spectrometry (MALDI-TOF and HR-ESI), it has been shown that Al(III) monophthalocyaninate [(OH)AlR4Pc] forms supramolecular dimers {[M4(XAlR4Pc)2]4+(X−)4}, whereas Al(III) μ-oxodiphthalocyaninate [(AlR4Pc)2(μ-O)] forms oxygen-bridged supramolecular dimers {[M4(XAlR4Pc)2(μ-O)]2+(X−)2}.

The adsorption and photodynamic efficiency of 5,10,15,20-tetrakis(p-sulfonatophenyl)porphyrin (H2TPPS4) on bilayer lipid membranes (BLM) have been studied. The adsorption of H2TPPS4 on BLM leads to rising of the potential drop on the membrane/water interface which has been detected either by the intramembrane field compensation (IFC) method, or as ζ-potential of liposomes measured by the dynamic light scattering method. The dependence of this potential on the concentration of H2TPPS4 and KCl in the solution can be described in the frame of Gouy-Chapman model of diffuse double layer assuming that the molecules of H2TPPS4 adsorb on the surface of BLM as an anions with four charged groups. The potential disappeared when the pH of solution decreased from 6 to 3 allowing the conclusion that the protonated forms of H2TPPS4 can not adsorb on the BLM probably due to change of conformation or aggregation of the molecules. The photodynamic efficiency of H2TPPS4 was evaluated by measuring the rate of damage of the targets - molecules of styryl dye (di-4-ANEPPS) by singlet oxygen generated under illumination on the surface of BLM. This rate was proportional to the surface density of H2TPPS4 molecules on the membrane which was determined from the change of surface charge of the membrane due to adsorption of the H2TPPS4. These results indicate that the di-4-ANEPPS molecules are damaged by singlet oxygen generated by monomers of H2TPPS4 molecules adsorbed on the membrane. The rate of oxidation of di-4-ANEPPS molecules adsorbed on the same (cis) side of the membrane together with the H2TPPS4 molecules was either the same or higher than that when di-4-ANEPPS molecules were adsorbed on opposite (trans) side. It indicates that the quenching of singlet oxygen by the di-4-ANEPPS molecules at cis side of the membrane was negligible, in contrast to our earlier study when singlet oxygen was generated by aluminum(III) phthalocyanines with one or two peripheral sulfo groups. The difference between these phthalocyanines and H2TPPS4 was explained by their different adsorption depth in the membrane.

The effect of additives of sensitizing Zn(II) and Co(II) complexes with 5,15-(diethoxyphosphoryl)-10,20-diphenylporphyrin on the mobility of holes in thin poly3-hexylthiophene films is studied. The charge carrier mobility is measured using the CELIV and photo-CELIV methods. It is found that the sensitizing additive does not affect the mobility of the equilibrium charge carriers, but causes a decrease in the mobility of the nonequilibrium charge carriers.

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.

The photochemical activity of the anionic form of two-decker ytterbium and lutetium pthalocyaninates (LnPc2, Ln = Yb, Lu) is observed in the process of electron transfer to 2-methyl-1,4-naphthoquinone (MNQ). Under illumination of solutions of LnPc2 (1 × 10–5 mol/L) and MNQ (5 × 10–5 mol/L) in dimethyl formamide by light with wavelength λph > 630 nm, the anionic form of the two-decker phthalocyaninate [(Pc2–)Ln3+(Pc2–)]– passes into the neutral monoradical form [(Pc2–)Ln3+(Pc–)]0•. The photochemical redox process is accompanied by accumulation of the reduced form of MNQ. The observed effect is the first example of electron phototransfer with the participation of two-decker lanthanide phthalocyaninates.

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.

Luminescence spectra of two novel P(V) porphyrin-based photosensitizers in aqueous and ethanol solutions were recorded in the visible and near IR spectral range. The singlet oxygen contribution into the luminescence signal was determined and singlet oxygen lifetimes were measured.

The formation of μ-oxo and μ-fluoro dimers based on aluminum tetra-15-crown-5-phthalocyanine Al[(15C5)4PcX], X = OH, OCH3 (I) was studied by UV-Vis and 1H NMR spectroscopy. It is established that the formation of μ-oxo dimer (μ-O)[(15C5)4PcAl]2 in chloroform solution occurs upon titration of I with methanol, ethanol, and dimethylsulfoxide, as well as at the Al2O3-eluent interphase, upon an increase of the methanol concentration in chloroform and upon storage of I in the solid state. It is shown for the first time that the interaction of [(15C5)4PcAl(OH)] with tetrabutylammonium fluoride in chloroform results in the formation of stable μ-fluoro dimer of (μ-F)[(15C5)4PcAl]2+, structure of which identified based on UV-Vis, 1H NMR, and MALDI-TOF mass spectral data. Conditions for preparation of complex [(15C5)4PcAlF2]− in solutions are found, and the possibility of sequential transformations in the series of complexes [(15C5)4PcAl](OH) → [(15C5)4PcAlF2]− → (μ-F)[(15C5)4Pcal]2+ is shown.

Thiol- and thioacetate-based functional groups enjoy much attention as anchors for building of self-assembled monolayers (SAM), while SAM formation based on readily accessible benzoyl derivatives remain unexploited. In the present work, we study the SAM-forming ability of a simple octylthiobenzoate and a redox-active metal-free phthalocyanine bearing two thiobenzoyl-terminated diethyleneglycol chains. By the means of cyclic voltammetry for both solutions and SAMs of the studied phthalocyanine compound, it was demonstrated that this anchoring group does indeed allow formation of densely packed SAMs from the thiobenzoyl-containing compounds on gold surface without the need in additional ex situ deprotection synthetic step. This approach could be used for further design of novel building blocks for SAM containing this anchor group.

This review summarizes the synthetic approaches towards oxa-crown-substituted phthalocyanines (CRPc’s) including various metal complexes of s-, p-, d-, and f-elements. The template cyclotetramerization of phthalonitriles and direct metalation pathways for synthesis of target compounds are discussed and compared. It is demonstrated that obtained results have contributed to coordination, supramolecular, and materials chemistry of phthalocyanines in general. An analysis of the results published to date reveals the challenges of these compounds for their use in high-tech applications.

Asymmetric membrane materials based on MC-40 membranes modified with a thin layer of MF-4SC perfluorinated ion exchangers with introduced polyaniline were obtained. The diffusion parameters of the resulting composites were studied. The anomalous asymmetry of ion transport in neutral solution was found. The diffusion coefficients of individual cations in the membranes with mixed cationic compositions were estimated. The conductivity of the composites was studied. The activation energies were evaluated. It was found that the membranes containing 2% polyaniline exhibited a maximum ionic conductivity, which is consistent with a model of the limited elasticity of membrane pores.

The electronic-spectroscopy technique is used to study the properties of solutions of double-decker diphthalocyanine complexes of lanthanides LnPc2 (Ln = Ho, Er, Yb, Lu) in chloroform, dimethylformamide, water-micellar systems, solutions of proteins, and polymers, as well as on the surface of silica nanoparticles. In all the studied systems, a correlation is established between the positions of maxima of absorption bands of LnPc2 and the ionic radius of the complexing metal. Redox processes determined by the nature of the solubilizer are detected in supramolecular associates of LnPc2 with macrocompounds and nanoparticles. Finally, prototypes of sensor systems are suggested for determination of albumin and silica nanoparticles in solutions. Films of polyvinyl pyrrolidone and polyvinyl alcohol containing LuPc2 and YbPc2 are obtained, for which sensor response to albumin and nanosilica is also established. On the whole, the results show good prospects for development of sensor devices based on the studied systems.

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 A. 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.

The nonlinear optical properties of solutions of (2,3,9,10,16,17,23,24-tetra-15-crown-5-phthalocyaninato)indium(III) [(15C5)4Pc]In(OH) in tetrachloroethane (TCE) have been studied by the z-scan method. It has been found that a nonlinear optical response is due to supramolecular associates formed in a tetrachloroethane solution by heating to 90°C/slow cooling to room temperature cycling. The formation of the supramolecular associates has been studied by atomic force microscopy (AFM) and electronic absorption spectroscopy (EAS). It has been shown that a single thermal treatment of [(15C5)4Pc]In(OH) solutions in TCE results in the predominant formation of dimers, as evidenced by both a short-wavelength shift of the Q-absorption band of the monomeric complex (λmax = 692 nm) to the band of λmax = 653 nm and height doubling of molecular entities as measured by AFM. The dimers are responsible for the two-photon absorption measured in the femtosecond range, which has a relatively high cross section of σ2 = 1.38 × 10−46 cm4 s/(molecule, photon) or 1.38 × 104 GM. According to the AFM data, three cycles of heat treatment of the solution leads to the formation of supramolecular assemblies of about 200 nm length. The optical spectrum exhibits long-wavelength absorption at λmax = 841 nm and the long-wavelength edge near 1300 nm. In the case of nanosecond 1064-nm laser irradiation, the linear absorption S 0 → S 1 is primary, having the cross section of σ0 = α0/N = 2.3 × 10−20 cm2. The known high quantum yield (close to unity) of triplet states of indium phthalocyanines suggests that the main nonlinear optical effect is determined by intersystem crossing S 1 → T 1 and triplet-triplet absorption T 1 → T 2. The absorption cross section is σ T-T = 1.14 × 10−19 cm2.

In the present work, we demonstrate that transversal conductivity and, consequently, electrochemical activity of ultrathin solid films of two structurally similar octa-butoxy and tetra-crown-ether substituted europium bisphthalocyaninates are quite different. It is shown that presence of the crown moieties allows excellent transfer of charge through monomolecular ultrathin films of respectively substituted complex. This enables their redox-multistability, which can be utilized in molecular logic and information storage devices. On the other hand, transversal charge transfer is inhibited in the films of octa-butoxy-substituted bisphthalocyaninate, which might be promising for organic field-effect transistor applications.

X-ray diffraction analysis was used to establish the structure of aluminum(iii) alkoxide tetra-15-crown-5-phthalocyaninate complex.

Peculiarities of the interaction between a heteroleptic triple-decker terbium(III) complex of a general type [Br4TPP]Tb[(15C5)4Pc]Tb[(15C5)4Pc] (Tb-TD*, where Br4TPP = 5,10,15,20-tetra-(4-bromophenyl)-porphyrin and (15C5)4 Pc = tetra-(15-crown-5)-phthalocyanine) and potassium cations in different solvents are studied. The interaction between Tb-TD* and potassium acetate is found to proceed via either the supramolecular dimerization of the complex or the inclusion of the cations between the crown-containing molecular decks depending on the polarity of the media. From the analysis of the titration curves, the stability constant of Tb-TD* × 4K+ adduct in a chloroform : methanol = 1 : 1 mixture was estimated. The stability constant of the aggregate was found to exceed the known values of similar compounds by over ten orders.

Techniques of the production of polymer nanocomposites based on tetrapyrrole compounds with photoelectric, nonlinear optical, and photorefractive properties are considered. Supramolecular ensembles of Ru(II) and Ga(III) complexes with tetra-15-crown-5-phthalocyanine are found to form upon the deposition of thin films from tetrachloroethane solutions that have undergone several cycles of heating followed by slow cooling. The surface formation of supramolecular ensembles is studied with the use of atomic force microscopy. The assemblage is found to give rise to photoelectric and photorefractive sensitivity in the near-infrared range (measurements were carried out at 1064 and 1550 nm). The quantum yield of thermalized electron-hole pairs at 1064 nm in composites of polyvinyl carbazole and assembled Ga(III) complexes is 20 times as high as that in composites based on Ru(II) complexes. The largest two-beam coupling gain coefficient at 1064 nm (Γ = 120 cm−1 at E0 = 120 V/μm) was also observed for the Ga(III)-complex-containing composite. The third-order dielectric molecular susceptibility measured in tetrachloroethane solutions of the complexes weakly depends on the nature of the central atom and its axial neighborhood and falls in a range of γ = 4−5.2 × 10−32 esu.

Photosensitizers are widely used as photodynamic therapeutic agents killing cancer cells by photooxidation of their components. Development of new effective photosensitive molecules requires profound knowledge of possible targets for reactive oxygen species, especially for its singlet form. Here we studied photooxidation of voltage-sensitive styryl dyes (di-4-ANEPPS, di-8-ANEPPS, RH-421 and RH-237) by singlet oxygen on the surface of bilayer lipid membranes commonly used as cell membrane models. Oxidation was induced by irradiation of a photosensitizer (aluminum phthalocyanine tetrasulfonate) and monitored by the change of dipole potential on the surface of the membrane. We studied the drop of the dipole potential both in the case when the dye molecules were adsorbed on the same side of the lipid bilayer as the photosensitizer (cis-configuration) and in the case when they were adsorbed on the opposite side (trans-configuration). Based on a simple model, we determined the rate of oxidation of the dyes from the kinetics of change of the potential during and after irradiation. This rate is proportional to steady-state concentration of singlet oxygen in the membrane under irradiation. Comparison of the oxidation rates of various dyes reveals that compounds of ANEPPS series are more sensitive to singlet oxygen than RH type dyes, indicating that naphthalene group is primarily responsible for their oxidation.

The photoelectric and photorefractive characteristics of composites based on poly(vinylcarbazole) containing crown-substituted ruthenium phthalocyanine with axially coordinated pyrazine molecules, (R4Pc)Ru(pyz)2 (where R4Pc−2 is [4,5,4′,5′,4″,5″,4″′,5″′-tetrakis-(1,4,7,10,13-pentaoxatridecamethylene)phthalocyanine ion], pyz is pyrazine), have been studied. Supramolecular ensembles of these complexes are responsible for optical absorption and photoelectric and photorefractive sensitivity in the near IR region. It has been found that under the action of a 1064-nm laser, the quantum efficiency of formation of mobile charge carriers, estimated from the photocurrent, corresponds to the Onsager equation when the quantum yield of formation of thermalized electron-hole pairs φ0 = 0.35 and the separation distance is 9.8 A, irrespective of the (R4Pc)Ru(pyz)2 content. The kinetic curves of amplification of the information laser beam are bellshaped. This suggests that the photorefractive characteristics are underestimated owing to lowering to zero of the field E0 inside the layer as a result of buildup of space charge in the near-electrode space upon passing the dark current. The two-beam gain coefficient at an (R4Pc)Ru(pyz)2 content of 7 wt % is Γ = 62 cm−1 as estimated from the maximum of the bell-shaped curve.

The spectral, electrochemical, and optical properties of Langmuir-Blodgett films (LBFs) and cast films from a solution of new double-decker cerium bis[tetra-(15-crown-5)-phthalocyaninate] (Ce(R4Pc)2) are studied. Based on analysis of compression isotherms and quantum-chemical calculations, schemes of the organization of Ce(R4Pc)2 molecules at different states of its monolayers are proposed. Correlation dependences are determined in order to relate the optical and electrochemical characteristics of monolayers and LBFs of sandwich-type lanthanide phthalocyaninates to the ionic radii of their metal centers. The valent state of Ce ions in a monolayer-forming complex is determined, and a sequence of redox transformations occurring in LBF uppon appliance of a potential is proposed, one of the transformations being associated with the Ce3+/Ce4+ redox transition. Orientation-induced intramolecular electron transfer is revealed in the planar supramolecular system. It is shown that, during the formation of a monolayer from a Ce(R4Pc)2 solution, a tetravalent metal center passes to a trivalent state. Monolayer compression to a high surface pressure reverts the complex to the electronic state typical of the solution. The reversible transformations observed upon the monolayer compression result from intramolecular electron transfer from the 4f-orbital of Ce to the phthalocyanine ring and backwards. The high operation rate and the reversibility of switching between the stable states, which are determined by means of the surface plasmon resonance technique, upon a stepwise change in the electrode potential within the range of 200–850 mV may underlie the development of optoelectronic systems. With a large number of molecules in a stacking aggregate, changes in the distance between the decks of the complex that occur with changes in the oxidation level of the metal center can substantially modulate the sizes of molecular ensembles. A supramolecular device capable of performing mechanical work can be developed based on this effect.

The spectral and electrochemical properties of Langmuir-Blodgett (LB) films of homoleptic double-decker cerium bis-[tetra-15-crown-5]-phthalocyaninate Ce[R4Pc]2 and its heteroleptic analog [Pc]Ce[R4Pc] were studied. It was shown that during formation of Langmuir monolayers upon contact of both complexes solutions with water subphase the metal center with valent state IV in the solution transforms into one with the valent state III in the monolayer. Upon cyclic compression-expansion of these monolayers, orientation-induced reversible intramolecular transfers of electron from 4f orbital of cerium ion to the phthalocyanine macrocycle (compression) and in reverse direction (expansion) occur in a planar supramolecular system. Scheme of reversible electrochemical transformations occurring in ultrathin films of double-decker cerium crown-phthalocyaninates, one of which is associated with the Ce+3/Ce+4 redox-transition of metal center of the complex, was proposed and substantiated using the results of spectro-electrochemical investigations. It was shown that one of these transformations is associated with the Ce+3/Ce+4 redox transition of metal center of the complex and upon change of metal center oxidation state its size changes, and, consequently, the distance between the decks of the complex also changes. This change in the distance can lead to a substantial (13–15%) modulation of the linear size of molecular assemblies with a large number of molecules in stack. On the basis of this effect the supramolecular device that can perform mechanical work can be developed. Using surface plasmon resonance technique we have demonstrated that a step change in electrode potential in region of 200–1000 mV induces a corresponding optical response reflected in a step change of the resonance angle. High operation speed and reversibility of switching between stable states can serve as a basis for development of optoelectronic switching systems.

Physico-chemical properties of monolayers of tetra-15-crown-5-phthalocyanine ligand were studied using LangmuirBlodgett technique and fiber optic spectroscopy. Dependences between concentration of monolayer forming solution and phthalocyanine ligand aggregation degree in monolayer were established. True stable monolayers of tetra-15crown-5-phthalocyanine ligand at the air/water interface were formed with orientation of phthalocyanine macrocycle planes parallel to the subphase surface. It was proven that absence of aggregates in solution does not guarantee absence of aggregation in the monolayer upon its formation. It was shown that studied substance generates columnar aggregates upon compression even in monolayer formed from extremely diluted solutions. Using special IR-spectroscopy techniques, it was shown that orientation of molecules relative to the substrate surface remains the same upon formation of solid ultrathin films by Langmuir-Blodgett technique.

Poly(N-vinylcarbazole) layers containing tetra-5-crown-5-gallium phthalocyaninate (R4Pc)Ga(OH) are shown to possess photoelectric and photorefractive sensitivity at a wavelength of 1064 nm. This effect is associated with the formation of supramolecular ensembles of (R4Pc)Ga(OH) molecules with electronic optical absorption in the near-IR range and nonlinear optical properties. For the composite containing 5 wt % (R4Pc)Ga(OH) supramolecular ensembles, the dependence of the quantum efficiency of mobile-charge photogeneration on electric field E0 is well fit by the Onsager equation expanded to E03 at a quantum yield of electron-hole pairs of φ0 = 0.9 s with an initial separation radius of r0 = 9.8 A susceptibility χ(3) equal to 1.85 × 10−10 esu is measured via the well-known method of electric-field-induced second-harmonic generation. Two-beam-coupling gain coefficient Γ is found to be 80 cm−1 at E0 = 120 V/μm.

Erbium mono-, bis-, and tris(phthalocyaninates) with tetra-15-crown-5-phthalocyanine (H2R4Pc) were synthesized and studied by spectroscopic methods. The complexes were obtained by reacting H2R4Pc with erbium salts in high-boiling solvents. To compare the efficiency of two approaches to the synthesis of double-decker lanthanide phthalocyaninates, bis(phthalocyaninate) [Er(R4Pc)2] was also obtained by a template procedure from dicyanobenzo-15-crown-5. A combination of physicochemical methods (UV and IR spectroscopy, MALDI-TOF mass spectrometry, 1H NMR) was used for identifying the compounds and proving their individuality and structure. The photoluminescence method demonstrated that solutions of erbium bis- and tris(phthalocyaninates) in CHCl3 are nonfluorescent in the visible range of light whereas solutions of mono(phthalocyaninate) in CHCl3 and DMSO exhibit fluorescence with maxima at 707 and 695 nm, respectively. The oxidation of erbium mono(phthalocyaninate) leads to fluorescence quenching.

The interaction between neutral, lanthanide bis(tetra-15-crown-5-phthalocyaninate) complexes Ln[(15C5)4Pc] 2 0 , (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.

Cation-promoted supramolecular assembly of cobalt(II) and ruthenium(II) tetra-15-crown-5-phthalocyaninates is comparatively studied using the electronic absorption and infrared spectroscopy. The effects of the nature of the receptor and substrate on the architecture of the supramolecular aggregates formed are discovered. By contrast to Cu(II), Zn(II), and Ni(II) tetra-15-crown-5-phthalocyaninates, Co(II) and Ru(II) complexes are found to demonstrate sodium-potassium selectivity determined by the peculiarities of supramolecular structures formed upon the interaction with the cations.

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.

The methods of electron absorption spectroscopy and 1H NMR were used to study the processes of interactions between zinc tetra-(15-crown-5)-phthalocyaninate and a number of N-donor ligands, including 1,4-diazabicyclo[2.2.2]octane, 4-dimethylaminopyridine, 3-aminopyridine, imidazole, 2-amino-5-methylpyridine, 2-methyla-4-aminopyridine, 2,3-diaminopyridine, pyrazine. A new effective method for synthesizing zinc tetra-15-crown-5-phthalocyaninate was developed that allowed one to obtain the complex at a yield of greater than 80% under simple conditions in 2 h. The structure of associates was studied in detail using the example of interactions between zinc tetra-15-crown-5-phthalocyaninate and 1,4-diazabicyclo[2.2.2]octane. 1H NMR studies in a wide temperature range of 213–323 K (−60 to +50°C), as well as quantum-chemical calculations, allowed us to establish the formation of two types of associates of phthalocyanine and 1,4-diazabicyclo[2.2.2]octane with the composition of 1: 1 and 2: 1. Up to a temperature of 253 K, the 1: 1 and 2: 1 associates are in equilibrium with a high rate of interconversion.

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.

Processes of aniline polymerization in perfluorinated polysulfonic acid MF-4SK solution are studied by UV-spectroscopy. Membranes with polyaniline-modified surface layer are synthesized. It is shown by voltammetry and potentiometry that the composite materials demonstrate asymmetric ion transfer with respect to protons and sodium cations.

A method of preparing MF-4SK membranes with the anisotropic distribution of aniline over the thickness is developed. The processes of aniline polymerization in the matrix of the MF-4SC sulfocationite membrane are investigated via electronic-absorption and IR spectroscopy. The processes of ion transport in the obtained composite membranes are studied via impedance spectroscopy, voltammetry, and potentiometry.

Two series of heteroleptic crown-substituted tris(phthalocyaninate) complexes (Pc)Ln[(15C5)4Pc]Ln(Pc) and [(15C5)4Pc]Ln[(15C5)4Pc]Ln(Pc), where 15C5 is 15-crown-5, (Pc2−) is the phthalocyaninate dianion, Ln = Nd, Eu, Ho, Er, and Yb, were prepared by the reaction of tetra-15-crown-5-phthalocyanine H2[(15C5)4Pc] with the corresponding lanthanide acetylacetonates and lanthanum bis(phthalocyaninate) La(Pc)2, which was used as a phthalocyaninate dianion donor. The composition and structure of the synthesized complexes were confirmed by MALDI TOF mass spectrometry, UV-Vis absorption spectroscopy, and 1H NMR. Complete assignment of the proton resonance signals of the paramagnetic lanthanide complexes was based on analysis of lanthanide-induced shifts.

Polyvinylcarbazole layers containing ruthenium (II) tetra-15-crown-5-phthalocyanate axially coordinating ethylisonicotinate molecules are found to have photoelectric and photorefractive sensitivity at 1550 nm. The effect is determined by the formation of supramolecular ensembles with the electronic optical absorption and photoelectric sensitivity in the near IR range up to 1600 or 1700 nm and nonlinear optical properties. A photorefractive two-beam coupling gain coefficient Γ measured at 1550 nm increases with an increase in the Ru(II) complex content in the polymer layer and equals 25 cm−1 at 6 wt %. The difference between the coupling gain and absorption coefficients (the actual gain coefficient) is Γ − α = 19 cm−1. Additionally introducing 3 wt % C60 fullerene into the layer does not change the characteristics, but the subsequent preirradiation (irradiation of the whole layer with a 633-nm laser beam in a range of the optical absorption of C60 before recording photorefractive curves) results in an increase in the gain coefficient at 1550 nm up to Γ = 48.3 cm−1 and, hence, in Γ − α = 42.3 cm−1. A time constant of the diffraction grating formation is about τ = 0.8 s.

Methods of obtaining porphyrin-containing polymer materials that have electroluminescent properties are analyzed. Based on the data, a strategy for producing the most effective porphyrin precursors for the further synthesis of highly ordered polymer materials is developed. Synthetic approaches are found and two meso-substituted porphyrins, i.e., 5,15-diphenyl-10,20-dibromoporphyrin (1a) and 5,15-diethynylphenylporphyrin (2a), are synthesized.

The images of ensembles of ruthenium(II) complexes with tetra-15-crown-5-phthalocyanine and axially coordinated triethylenediamine molecules, (R4Pc)Ru(TED)2, obtained on an atomic force microscope were analyzed. A comparison with the X-ray structure analysis data was performed to estimate the number and mutual arrangement (architecture) of molecules in supramolecular aggregates depending on the nature of the solvent and the temperature of solutions before casting. Storage at room temperature or heating of a solution of the complex in tetrachloroethane caused the formation of stable supramolecular “wires” 600 nm or more long. The z-scanning method was used to study the third-order nonlinear optical characteristics of solutions of the (R4Pc)Ru(TED)2 complex in tetrachloroethane.