Zirconiumphthalocyanine: Darstellung und Eigenschaften chloridhaltiger Phthalocyanine des drei- und vierwertigen Zirconiums; Kristallstruktur von cis-Di(triphenylphosphin)iminium-tri(chloro)phthalocyaninato(2–)zirconat(IV)-di(dichlormethan)

Zirconiumphthalocyanines: Synthesis and Properties of Chloride Ligated Phthalocyanines of Ter- and Quadrivalent Zirconium; Crystal Structure of cis-Di(triphenylphosphine)iminium-tri(chloro)phthalocyaninato(2–)zirconate(IV)-di(dichloromethane) cis-Di(chloro)phthalocyaninato(2–)zirconium(IV) is obtained by the reaction of ZrCl₄ with phthalodinitrile in 1-chloronaphthaline at 230°C. It reacts with molten di(triphenylphosphine)iminiumchloride ((PNP)Cl) yielding cis-di(triphenylphosphine)iminium-tri(chloro)phthalocyaninato(2-)zirconate(IV), cis-(PNP)[ZrCl₃Pc^2?]. This crystallizes with two molecules of dichloromethane in the monoclinic space group P2₁/n with the lattice constants a = 15.219(4) Å, b = 20.262(10) Å, c = 20.719(4) Å, b? = 93.46(2)°, Z = 4. The seven coordinated Zr atom is situated in a “square base-trigonal cap” polyhedron. The plane of the three chlorine atoms runs parallel to the plane of the four isoindole nitrogen atoms N_iso. The Zr–Cl distances range from 2.49 to 2.55 Å, the Zr? N_iso distances from 2.26 to 2.29 Å. Due to ion packing effects the Pc^2? ligand shows an asymmetrical convex distortion. The PNP cation adopts the bent conformation. The P? N? P angle is 139°, the P? N distance 1.58 Å. As confirmed by the cyclovoltammograms cis-(PNP)[ZrCl₃Pc^2?] is oxidized (anodically or chemically by Cl₂) to yield cis-tri(chloro)phthalocyaninato(1–)zirconium(IV) and reduced (cathodically or chemically by [BH₄]^?) yielding chlorophthalocyaninato(2–)zirconium(III) and cis-di(triphenylphosphine)iminium-di(chloro)phthalocyaninato(2–)zirconate(III). The optical spectra show the typical π–π*-transitions of the Pc^2? resp. Pc^? ligand not much affected by the different states of oxidation and coordination of zirconium. The same is true for the vibrational spectra of the Pc^2? resp. Pc^? ligand. In the f.i.r. spectra between 350 and 150 cm^?1 the asym. and sym. Zr? Cl stretching and Cl? Zr? Cl deformation vibration as well as the asym. Zr? N stretching vibration of the [ZrCl_xN₄] skeleton (x = 1–3) is assigned.     

Structural, Electronic, and Optical Properties of Noble Metal Clusters from First Principles

We examine low-energy isomeric forms, static polarizabilities, and optical absorption spectra of Ag _n , n = 2–8, and Au _n , n = 2–3, clusters using first principles computations within the static and time-dependent versions of the density functional theory. The noticeable decrease in the static polarizabilities of Ag₇ and Ag₈ compared to the values characteristic of Ag _n , n = 2–6, is correlated with the transition from two-dimensional to three-dimensional structures at n = 7. The optical spectra computed within the time-dependent local density approximation for the most stable structures are in good agreement with the available experimental data and the results of earlier theoretical studies. Optical spectra of higher-energy isomers typically present features that are not observed in the experimental spectra. The d electrons affect the spectra of noble metal clusters by quenching the oscillator strengths through screening of the s electrons and by getting directly involved in the excitations. Due to the larger s–d hybridization in Au compared to Ag, these effects are more pronounced in Au _n clusters.     

The microstructure and optical transmittance thermal analysis of sodium borosilicate bio-glasses

The conditions to fabricate the bulk porous specimens have been studied on account of sodium borosilicate (NBS) glasses. Glass composition, heat treatment at phase separation and TiO₂ addition have been considered in this study. Original glass samples of composition in mol%: sample A: 9.19 Na₂O - 23.58 B₂O₃ - 67.23 SiO₂, sample B: 9.29 Na₂O - 3.17 TiO₂ - 23.82 B₂O₃ - 63.72 SiO₂ were prepared by melting reagent grade chemicals (Na₂CO₃, HBO₃, SiO₂ and AgNO₃) in platinum crucibles at 1480°C for 1 h in air. The melts were poured onto stainless steel plates and were annealed at 500°C for 0.5 h after cooling. Thus, obtained samples were phase separated at 700°C for 2, 15, 25 and 50 h to study their microstructure by scanning electron microscope (SEM). Besides the direct study of the microstructure by SEM, information on glass structural changes of samples are provided by measuring in situ changes by the optical transmittance thermal analysis. The isothermal measurements were carried out at 700, 720 and 740°C. The temperature of phase separation, the leaching and nucleator addition (TiO₂), significantly influence the microstructure of the resulting leached product. TiO₂ additive seems to suppress crystallization of cristobalite: especially at the extended above heat treatment phase separation runs. The phase-separated domains of glasses containing above 80 moles of SiO₂ are so small that it is very hard to observe them by SEM. The glass composition in our case was selected in a way to have relatively large phase separated areas easily observed by SEM at magnification 20 000·. The influence of TiO₂ is not too pronounced. It seems to suppress the cristobalite crystallization, especially of longer heating runs. The image analysis of leached glasses shows the prevailing content of the skeletal phase in a comparison to pores. The TiO₂ content diminishes the content of the skeletal phase. This revised version was published online in July 2006 with corrections to the Cover Date.     

Interpolymer complexes of a new type

A new type of three-component interpolymer complexes (3IPCM) formed by two similarly charged polyelectrolytes and an oppositely charged low molar mass compound was studied by DSC, NMR and X-ray methods. The low molar mass monobasic compounds in these complexes act as mediators. This type of complexes differs from earlier-obtained 3IPCM, which contained a dibasic low molar mass mediator.The present 3IPCM were obtained from two polymers (polyacrylic acid and sodium polyphosphate) and bases such as 4-vinylpyridine and 2-methyl-5-vinylpyridine.The authors express their acknowledgement to the Russian Science Foundation for sponsoring research projects 93-03-5650 and 93-03-18682.     

Mo(W)-Cu(Ag)-S簇合物的非线性光学性能研究

本文介绍了非线性光学性测试中的Ｚ－扫描方法。总结了Ｍｏ（Ｗ）－Ｃｕ（Ａｇ）－Ｓ簇合物的光限制效应、非线性吸收和非线性折射等光学性质。讨论了簇合物结构与光学性能的关系。     

Analysis of nickel-niobium alloys by inductively coupled plasma optical emission spectrometry

Inductively coupled plasma optical emission spectrometry (ICP-OES) was applied to the analysis of major and minor elements of Ni-Nb alloys obtained by aluminothermic reduction process. Digestion of samples was made using a mixture of HF+HNO₃. Minor and trace elements were determined without matrix separation. The precision for all constituents was <3%. Recoveries for the analyte-spiked samples were 95%.     

用胆甾型苯并—15—冠—5气相色谱固定相分离乳酸和乳酸乙酯光学异构体

胆甾型苯并－１５－冠－５（简称ＣＨ－Ｂ－１５－Ｃ－５）在不同温度范围内的相态不同，在同一温 度范围内因处理方式不同而物性亦相去甚远，用其作成的ＧＣ固定相兼具气固色谱（ＧＳＣ）、 普通气液色谱（ＧＬＣ）和冠醚液晶气液色谱（ＣＬ－ＧＬＣ）多种功能。用该固定相在不同条件下对 乳酸和乳酸乙酯光学异构体混合物的分高效果进行了比较研究，并探讨了手性拆分机理。     

Induced Absorption of C60 and a Water-Soluble C60-Derivative in SiO2 Sol-Gel Matrices

Porous sol-gel glasses, either impregnated with pure C₆₀ or doped with a methanofullerene derivative, have been studied and induced absorption or reverse saturable absorption (RSA) has been observed in both types of solid materials. The samples impregnated by pure C₆₀ mainly contain well-dispersed fullerene molecules. Unlike crystalline films of C₆₀, their absorption dynamics can be well described by a 5-level model, developed for non-interacting C₆₀-molecules in solutions. Methanofullerene samples, on the other hand, show signs of micellar aggregation and therefore RSA dynamics that are influenced by solid state effects. We observe an important decrease of transmission at high fluences for both kinds of samples, a shortened singlet-state lifetime to that observed in solution, but nonetheless, a triplet yield, that cannot be considered as negligible. In the case of pure C₆₀ in a sol-gel matrix, we can explain the faster de-excitation dynamics, relative to behavior in solution, mainly by the absence of stabilizing aromatic solvents and also by the interaction of the amorphous environment with the molecules. Concerning the methanofullerene samples, the acceleration of the de-excitation dynamics can be principally attributed to solid-state effects due to the micellar aggregation.     

Electrochemically Induced Iron Release of Adsorbed Horse Spleen Ferritin: Quantitation of Iron Using Long Optical Path Length Thin‐Layer Spectroelectrochemistry

In this work, long optical path length thin‐layer electrochemical cell was constructed using indium‐tin oxide on glass as the electrode material. Iron release from ferritin adsorbed on the electrode was induced by applying a negative potential sweep in the presence of 1,10‐phenanthroline. The usefulness of spectroelectrochemistry as a means of determining the quantity of iron released from an adsorbed layer of ferritin is demonstrated.     

Sol–Gel SiO2-ZrO2 Coatings for Optical Applications

SiO₂-ZrO₂ based nanostructured multilayers films have been prepared by sol–gel processing from metallorganic precursors by low temperature inorganic polymerization reactions. Simultaneous gelation of both precursors was realized. Homogeneous and transparent films were obtained at room temperature by dip- and spin-coating on glass and silicon wafer substrates. Samples with successively deposited layers (1–3 layers) and successive thermal treatments have been also studied. Each deposited layer was thermally treated for 1 h at 300°C. The coatings were characterized by XRD, spectroellipsometry (SE), UV-VIS spectroscopy and AFM methods. The influence of substrates, number of coatings and number of thermal treatments on the optical and structural properties of the films was established. The thickness of three deposited SiO₂-ZrO₂ layers is about 496 nm on glass substrates and 413 nm on the silicon wafer substrate. The films deposited on glass are more porous than those deposited on silicon. The properties of optical waveguide prepared from SiO₂-ZrO₂ layers on silicon substrates will be discussed.