31P, ¹⁷O, and ¹⁰³Rh NMR spectroscopy shows that rhodium(III) reacts with phosphoric acid to generate polynuclear aquaphosphate complexes in which phosphate ions mostly have a bridging function. Assignment of ¹⁰³Rh NMR signals in dominant rhodium complexes is suggested.

THE STATE OF Al(III) IN ALCOHOL SOLUTIONS OF ALUMINUM ALKOXIDE AS PROBED BY ²⁷Al AND ¹³C NMR AND SMALL-ANGLE X-RAY SCATTERING

M.A. Fedotov, V.V. Molchanov, R.N. Zotov, F.V. Tuzikov
Russ. J. Inorg. Chem., 53(10) (2008) pp. 1621-1627.

Solutions of aluminum alkoxides obtained by interaction of aluminum metal with methyl, ethyl, and isopropyl alcohols were studied by ²⁷Al and ¹³C NMR and small-angle X-ray scattering. Alkoxides with a tetrahedral environment of aluminum prevail in methanol solutions, and those with an octahedral environment of aluminum predominate in ethanol solutions. In isopropyl alcohol at 293 K, polynuclear alkoxides with tetrahedral, octahedral, and pentacoordinated aluminum environments coexist. The structure of polynuclear complexes was refined by comparison of their calculated dimensions with small-angle X-ray scattering data.

EFFECT OF TEMPERATURE ON THE STRUCTURAL CHARACTERISTICS OF ZIRCONIUM DIOXIDE NANOPARTICLES PRODUCED UNDER CONDITIONS OF MICROWAVE TREATMENT

P.E. Strizhak*, A.I. Tripol’sky*, T.N. Gurnik*, F.V. Tuzikov, E.M. Moroz, T.E. Konstantinova**, N.A. Tuzikova, V.P. Kolko, I.A. Danilenko**, O.A. Gorban**
(*Pisarzhevskii Institute of Physical Chemistry, Kyiv, Ukraine; **Galkin Donets’k Physicotechnical Institute, Donets’k, Ukraine)

Theor. Exp. Chem., 44(3) (2008) pp. 144-149.

The effect of the sintering temperature on the structural characteristics of nanosized zirconium dioxide particles treated by microwave radiation during the drying process was investigated by small-angle X-ray scattering and the BET method. It was shown that the specific surface area, particle size, polydispersivity index, and surface and mass fractal dimensionality of zirconium dioxide depend on its heat treatment conditions.

A STUDY OF SOLID-STATE RHODIUM(III) SULFATES

S.N. Shagabutdinova*, M.A. Fedotov, A.V. Belyaev*, V.D. Il’yashevich**, E.I. Pavlova**
(*Nikolaev Institute of Inorganic Chemistry, Novosibirsk, Russia; **JSC Krastsvetmet, Krasnoyarsk, Russia)

Russ. J. Coord. Chem., 34(12) (2008) pp. 917-923.

Solid-state rhodium(III) sulfates and their aqueous solutions were examined by IR and electronic absorption spectroscopy, thermogravimetry, X-ray powder diffraction analysis, and ¹⁰³Rh and ¹⁷O NMR spectroscopy. A study of the spontaneous aquation of freshly prepared solutions showed that this process results in an equilibrium between the subsystems of monomeric and oligomeric complexes. It was found that solid-state rhodium(III) sulfates vary in phase composition, basically consisting of dimeric and trimeric complexes.

WATER DYNAMICS IN BULK AND DISPERSED IN SILICA CaCl₂ HYDRATES STUDIED BY ²H NMR

D.I. Kolokolov, I.S. Glaznev, Yu.I. Aristov, A.G. Stepanov, H. Jobic* (*Institut de Recherches sur la Catalyse, CNRS, France)

J. Phys. Chem. C, 112(33) (2008) pp. 12853-12860.

The mobility of water in deuterated analogues of CaCl₂xnH₂O (n = 2, 4, 6) hydrates has been studied by solid-state²H NMR spectroscopy. The dynamics of water molecules in the hydrates dispersed in the mesopores of silica are compared with the bulk state. Analysis of the ²H NMR line shape and T1 and T2 relaxation times allowed to characterize the dynamics of water in a wide temperature range (120-493 K). In both crystalline and melted hydrates, the mobility of water molecules is governed by O-D...Cl hydrogen bonding. Both the bulk and dispersed hydrates have been found to exhibit three types of molecular motion. Two of them represent fast internal and local motions performed on a time scale of 10^-10-10^-11 s. The third slow isotropic reorientation occurs on a time of 10^-610^-7 s. The dispersed hydrates become involved in the slow isotropic motion at a temperature 50-130 K lower than the corresponding bulk hydrates. The temperature TNMR at which the dispersed hydrates is involved in isotropic motion represents the melting point of the hydrates located in the silica pores. The decrease of the melting point for the dispersed hydrates is in a good accordance with Gibbs-Thompson effect for dispersed materials. In the dispersed hydrates, the water molecules reorient isotropically one order of magnitude faster in the temperature range 230-490 K, that is water is more mobile in the dispersed hydrates. The slow isotropic reorientation of water molecules is influenced by both the quantity of water in the hydrate and the dispersibility of the hydrates. In the case of the hydrate with n = 4, the activation energy of this motion decreases by ca. 3 times when the hydrate becomes dispersed in the silica pores.

¹H NMR SIGNAL BROADENING IN SPECTRA OF ALKANE MOLECULES ADSORBED ON MFI-TYPE ZEOLITES

E.E. Romanova*, C.B. Krause*, A.G. Stepanov, U. Wilczok**, W. Schmidt**, J.M. van Baten***, R. Krishna***, A. Pampel****, J. Kaerger*, D. Freude*
(*Universitat Leipzig, Leipzig, Germany; **Max-Planck-Institut fur Kohlenforschung, Mulheim, Germany; ***University of Amsterdam, Amsterdam, The Netherlands; ****Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany)

Solid State NMR, 33(4) (2008) pp. 65-71.

The anisotropic behavior of C₁–C₆ alkane molecules adsorbed in MFI zeolite was studied by¹H nuclear magnetic resonance (NMR) using single-pulse excitation, Carr–Purcell–Meiboom–Gill (CPMG) pulse sequence, Hahn echo (HE) pulse sequence, and magic-angle spinning. The molecular order parameter was obtained by both static ²H NMR spectroscopy and molecular simulations. This yields an order parameter in the range of 0.28–0.42 for linear alkanes in MFI zeolite, whereas the parameter equals zero for FAU zeolite with a cubic symmetry. Thus, in the case of a zeolite with a non-cubic symmetry like MFI, the mobility of the molecules in one crystallite cannot fully average the dipolar interaction. As a consequence, transverse nuclear magnetization as revealed in the echo attenuation notably deviates from a mono-exponential decay. This information is of particular relevance for the performance of pulsed field gradient (PFG) NMR diffusion experiments, since the occurrence of non-exponential magnetization attenuation could be taken as an indication of the existence of different molecules or of molecules in different states of mobility.

OBSERVATION OF PARAHYDROGENINDUCED POLARIZATION IN HETEROGENEOUS HYDROGENATION ON SUPPORTED METAL CATALYSTS

K.V. Kovtunov*, I.E. Beck, V.I. Bukhtiyarov, I.V. Koptyug*
(*International Tomography Center, Novosibirsk, Russia)

Angew. Chem. Int. Ed., 47(8) (2008) pp. 1492–1495.

It was demonstrated for the first time that heterogeneous hydrogenation of an alkene (propylene) with supported metal catalysts (Pt/ Al₂O₃, Pd/ Al₂O₃) leads to an observation of enhanced signals in the ¹H NMR spectra of the reaction product (propane) when hydrogen enriched in the para-H₂ spin isomer is used in the reaction. This observation indicates that hydrogen addition occurs pairwise to a measurable extent.

TEMPERATURE EFFECTS ON THE IR SPECTRA OF CRYSTALLINE AMINO ACIDS, DIPEPTIDES, AND POLYAMINO ACIDS: II. L-AND DL-SERINES

Yu.A. Chesalov, G.B. Chernobai*^,**, E.V. Boldyreva*^,**
(*Novosibirsk State University, Novosibirsk, Russia; **Institute of Solid State Chemistry and Mechanochemistry, Novosibirsk, Russia)

J. Struct. Chem., 49(4) (2008) pp. 627-638.

The IR spectra of L-and DL-serines H₃⁺-CH(CH₂OH)-COO⁻ (without diluents) were investigated in the temperature range 93–413 K; the changes in the IR spectra due to temperature variations were correlated with previously obtained diffraction data on anisotropic compression of structure and changes in the geometrical parameters of the hydrogen bonds.

STUDY OF THE TEMPERATURE EFFECT ON IR SPECTRA OF CRYSTALLINE AMINO ACIDS, DIPEPTIDS, AND POLYAMINO ACIDS: III.α-GLYCYLGLYCINE

Yu.A. Chesalov, G.B. Chernobai*^,**, E.V. Boldyreva*^,**
(*Novosibirsk State University, Novosibirsk, Russia; **Institute of Solid State Chemistry and Mechanochemistry, Novosibirsk, Russia)

J. Strut. Chem., 49(6) (2008) pp. 1012-1021.

The IR spectra of α-glycylglycine (H₃⁺N-CH₂-CO-NH-CH₂-COO⁻) are studied in the temperature range of 93 to 413 K. Changes in the spectra due to temperature variation are correlated with the previously obtained X-ray diffraction data on anisotropic compression of the structure and changes in the parameters of hydrogen bonding. Changes in the vibrational frequencies of NH₃⁺ and COO groups in the IR spectrum of α-glycylglycine are compared to changes in the vibrational frequencies of the same groups in the IR spectra of polymorphs of glycine, L- and DL-serine.

STUDY OF THE TEMPERATURE EFFECT ON IR SPECTRA OF CRYSTALLINE AMINO ACIDS, DIPEPTIDES, AND POLYAMINO ACIDS: IV. L-CYSTEINE AND DL-CYSTEINE

V.S. Min’kov*^,**, Yu.A. Chesalov, E.V. Boldyreva*^,**
(*Novosibirsk State University, Novosibirsk, Russia; **Institute of Solid State Chemistry and Mechanochemistry, Novosibirsk, Russia)

J. Struct. Chem., 49(6) (2008) pp. 1022-1034.

A study of the IR spectra of L-and DL-cysteine is carried out in a range of frequencies from 4000 cm⁻¹ to 600 cm⁻¹ and temperatures from 333 K to 83 K. Changes in the spectra of L- and DL-cysteine (NH₃⁺CH(CH₂SH)-COO⁻) on cooling are analyzed in comparison with the spectra of L- and DL-serine (NH₃⁺CH(CH₂OH)-COO⁻) and three polymorphs of glycine (NH₃⁺CH₂-COO⁻) previously studied under temperature variation. Changes in the IR spectra at variable temperatures are correlated with previously obtained diffraction data on anisotropic compression of the structure and changes in the geometric parameters of hydrogen bonds. Special attention is paid to temperature regions in which anomalies were detected by vibrational spectroscopy, X-ray diffraction, and calorimetry.

FT-IR AND FT-RAMAN SPECTRA OF FIVE POLYMORPHS OF CHLORPROPAMIDE. EXPERIMENTAL STUDY AND ab initio CALCULATIONS

Yu.A. Chesalov, V.P. Baltakhinov, T.N. Drebushchak*, E.V. Boldyreva*, N.V. Chukanov**, V.A. Drebushchak***
(*Institute of Solid State Chemistry, Novosibirsk, Russia; **Novosibirsk Institute of Organic Chemistry, Novosibirsk, Russia; ***Institute of Geology and Mineralogy, Novosibirsk, Russia)

J. Mol. Struct., 891(1-3) (2008) pp. 75-86.

IR- and Raman spectra were studied for five polymorphs of chlorpropamide (α, β, γ, δ and ε) (phase purity proved by DSC, X-ray single-crystal and powder diffraction). The equilibrium geometry and the vibrational spectra for different molecular conformations were calculated ab initio (DFT, B3LYP approximation). The assignment of the vibrational bands was made on the basis of the theoretical calculations and a comparison of the experimentally measured spectra for the crystalline polymorphs and the melt. The differences in the experimental vibrational spectra of the five chlorpropamide polymorphs were correlated with the X-ray structural data, and shown to be mainly due to the intermolecular interactions effect, and only to a smaller extent – to the conformational changes.

PHOTOCATALYTIC OXIDATION OF TABUN SIMULANT-DIETHYL CYANOPHOSPHATE: FTIR IN SITU INVESTIGATION

P.A. Kolinko, D.V. Kozlov

Environ. Sci. Technol., 42(12) (2008) pp. 4350-4355.

Gas phase photocatalytic oxidation of diethyl cyanophosphate vapor in a static reactor using TiO₂ and modified TiO₂ as the photocatalyst was studied with the FTIR in situ method. The transition metals Pt, Au, and Ag were used for TiO₂ modification by the chemical and photochemical deposition methods as well as the mechanical mixture of TiO₂ with manganese oxide to improve its adsorption and catalytic activity. Photocatalytic oxidation of diethyl cyanophosphate in a static reactor results in its complete mineralization with carbon dioxide, phosphoric and nitric acids, and water as the major final products. HCN was demonstrated to be the only toxic gaseous intermediate of diethyl cyanophosphate photocatalytic oxidation, formed as a result of diethyl cyanophosphate hydrolysis. Diethylphosphate and acetic and formic acids were registered as the surface intermediates. It was found that cyanhydric acid is oxidized slowly with the use of unmodified TiO₂. The formation of surface cyanide complexes with Ag and Au ions could be responsible for the fast removal of HCN from the gas phase and its further photooxidation in the case of using TiO₂ with deposited Au and Ag.

ISOPROPANOL DIFFUSION AND DEHYDRATION IN ZEOLITE HZSM-5. SPECTROKINETIC STUDY

T.S. Glazneva, V.P. Shmachkova, E.A. Paukshtis

React. Kinet. Catal. Lett., 94(1) (2008) pp. 11-20.

The isopropanol diffusion and dehydration in zeolite HZSM-5 were studied by FTIR spectroscopy. The alcohol dehydration was shown to start at the temperature above 60°C. It was found that at temperatures above 350°C, the isopropanol dehydration was limited by diffusion in the mesopores of zeolite. The method developed allows studying the kinetics of interactions of the reagent molecules with the OH-groups at the external surface of the zeolite and inside its channels.

BRONSTED ACIDITY OF GLASS FIBER MATERIALS

T.S. Glazneva, E.A. Paukshtis

Chem. Sustain. Devel., 16(4) (2008) pp. 473-478.

The results of investigation of acid properties of glass fiber materials by IR spectroscopy using the adsorption of ammonia, H/D exchange and isopropanol dehydration, are given. It is shown that the catalysts contain a large amount of Bronsted acid sites (BAS) with the strength comparable with that of BAS of zeolite HZSM-5. Number of BAS is proportional to Al content in the glass fiber. It is revealed that BAS are located in the bulk of the glass fiber. The centers located at up to 100 nm depth of a glass fiber are accessible for the reagent molecules of isopropanol.

SURFACE ACIDITY AND BASICITY OF OXIDE CATALYSTS: FROM AQUEOUS SUSPENSIONS TO IN SITU MEASUREMENTS

T.S. Glazneva, N.S. Kotsarenko, E.A. Paukshtis

Kinet. Catal.,

49(6) (2008) pp. 859–867.

The review covers the achievements of recent decades in the investigation of the acid–base properties of oxide catalyst surfaces. Both conventional and new investigation techniques are reviewed, including SSITKA for H/D exchange.

REVERSIBLE MODIFICATION OF MAGNETIC PROPERTIES OF Fe₃C NANOPARTICLES BY CHEMISORPTION OF CO

N.A. Ivanova*, A.A. Onischuk*, S.V. Vosel*^,**, P.A. Purtov*^,***, N.T. Vasenin, V.F. Anufrienko, V.N. Ikorski****
(*Institute of Chemical Kinetics and Combustion, Novosibirsk, Russia; **Institute of Geology and Mineralogy, Novosibirsk, Russia; ***Novosibirsk State University, Novosibirsk, Russia; ****International Tomography Center, Novosibirsk, Russia)

Appl. Magn. Reson., 33(3) (2008) pp. 285-291.

The paper is devoted to the electron spin resonance and magnetic measurements of Fe₃C nanoparticles covered by a carbon structure. There is a reversible modification of the magnetic properties by the chemisorption of CO and O₂. The CO chemisorption results in the transition of the majority of the Fe₃C nanoparticles from the ferromagnetic to the superparamagnetic state. The O₂ chemisorption results in the backward transition.

FORMATION OF DISPERSE FERROMAGNETIC NANOPARTICLES IN ZEOLITES IN THE COURSE OF THERMAL ACTIVATION IN OXYGEN

O.N. Martyanov, V.F. Yudanov

J. Struct. Chem., 49(3) (2008) pp. 421-426.

Samples of synthetic high-silica zeolites after high-temperature activation in oxygen are studied by ferromagnetic resonance. Observation of the fine structure of ferromagnetic resonance (FMR FS) indicates the formation of magnetic iron oxide nanoparticles in the course of thermal treatment of zeolites in oxygen. Features of the formation of a dispersed ferromagnetic phase in zeolites, geometric and magnetic characteristics of constituent nanoparticles are discussed.

STEPWISE MAGNETIZATION OF DISPERSED FERROMAGNETS DUE TO MAGNETIC INTERPARTICLE INTERACTIONS

S.N. Trukhan, O.N. Martyanov, V.F. Yudanov

Phys. Solid State, 50(3) (2008) pp. 456-462.

The main features of stepwise magnetization of dispersed ferromagnets caused by magnetic interparticle interactions are studied using a two-particle model. The ranges of values of the magnetic anisotropy constants of particles and of the dipole– dipole interaction between them are determined over which a reproducible jumpwise change in the magnetization of the system occurs in an external positive magnetic field. The proposed model is shown to explain the main specific features of the fine structure of the ferromagnetic resonance spectra.

FMR FINE STRUCTURE OF DISPERSED MAGNETS. PHYSICAL ORIGIN AND APPLICATIONS

O.N. Martyanov, S.N. Trukhan, V.F. Yudanov

Appl. Magnet. Resonance, 33 (2008) pp. 57-71.

An original approach is proposed to study the dipole-dipole interparticle interactions in dispersed magnets. This is the registration and analysis of the noise-like ferromagnetic resonance fine structure (FMR FS), which is caused by the magnetic dipole-dipole interaction between magnetic domains. The peculiarities of fine structure formation are discussed. The experimental examples of the possible FS method applications are summarized.

INFLUENCE OF Pd CODEPOSITION ON THE MAGNETIC PROPERTIES OF Co PARTICLES ON ALUMINA/NiAl(110)

O.N. Martyanov, T. Risse*, H.-J. Freund*

(*Fritz-Haber-Institut der Max-Planck Gesellschaft, Berlin, Germany)

J. Phys. Chem. B, 129(11) (2008) pp. 104705-104712.

Changes of the magnetic properties of ferromagnetic Co particles deposited at room temperature on a thin alumina film grown on a NiAl(110) substrate were investigated as a function of Pd coverage by subsequent deposition of Pd onto deposited Co particles. From previous X-ray photoelectron spectroscopy, IR, and temperature programmed desorption experiments it was concluded that Pd forms a shell on top of Co particles. However, the current experiments indicate that Pd does induce structural rearrangements within the Co particles which may also involve the intermixing of small amounts of Pd into the Co particles. The latter is inferred from a change in the -value for small particles. The impact of a larger intermixture of Co and Pd on the magnetic properties will be emphasized by a reversed deposition order where Pd particles were deposited first and subsequently covered by Co. The reversal of the deposition order increases the magnetic anisotropy of the particles considerably.

PREPARATION, MICROSTRUCTURE, MAGNETIC AND TRANSPORT PROPERTIES OF BULK TEXTURED Bi_1.8Pb_0.3Sr_1.9Ca₂Cu₃O_x AND Bi_1.8Pb_0.3Sr_1.9Ca₂Cu₃O_x +Ag CERAMICS

M.I. Petrov*, I.L. Belozerova**, K.A. Shaikhutdinov*, D.A. Balaev*, A.A. Dubrovskii*, S.I. Popkov*, A.D. Vasiliev*, O.N. Martyanov
(*Kirensky Institute of Physics, Krasnoyarsk, Russia; **Reshetnev Siberian State Aerospace University, Krasnoyarsk, Russia)

Supercond. Sci. Technol., 21(10) (2008) 105019.

A new method of preparation of bulk textured Bi2223 ceramics and Bi2223+Ag composites, based on room temperature pressing of foamed precursor (Bi2223, Bi2223+Ag) in a liquid medium, is proposed. SEM and XRD data prove a high degree of texture of the bulk samples obtained. Magnetic measurements performed in directions H || C–axis and H || a-b-planes of Bi2223 crystallites demonstrates anisotropy of magnetization confirming the texture of the ceramics. The materials obtained possess large diamagnetic response in the direction H || a-b-planes of Bi2223 crystallites at both 77.4 and 4.2 K.

FORMATION OF HOLLOW SPHERES UPON OXIDATION OF SUPPORTED COBALT NANOPARTICLES

P.A. Chernavskii*, G.V. Pankina*, V.I. Zaikovsky, N.V. Peskov*, P. Afanasiev**
(*Moscow Lomonosov State University, Moscow, Russia; **Institut de Recherche sur la Catalyse et Environnement, Villeurbanne, Cedex, France)

J. Phys. Chem. C, 112(26) (2008) pp. 9573-9578.

Oxidation of cobalt nanoparticles supported on montmorillonite was studied using transmission electron microscopy and temperature programmed reduction of the oxide particles. It has been shown that hollow shells of cobalt oxide were formed in this process, consisting of the mixture of CoO and Co₃O₄ oxides. A linear relationship between the thickness of shells and the initial particles size was established which suggests that both diffusion of cobalt ions through the oxide layer and diffusion of the oxygen into cobalt occur, but particles sintering is negligible compared with the reverse diffusion of cobalt. The lower critical diameter of cobalt particles was estimated, above which formation of hollow shells occurred. The hollow shells formation is suggested to be the reason for cobalt redispersion upon oxidation−reduction cycling of supported heterogeneous catalysts.

FORMATION OF SPHERICAL VOIDS IN THE OXIDATION OF Co NANOPARTICLES

P.A. Chernavskii*, G.V. Pankina*, V.I. Zaikovsky, N.V. Peskov*, V.V. Lunin*
(*Moscow Lomonosov State University, Moscow, Russia)

Russ. J. Phys. Chem. A, 82(4) (2008) pp. 690-693.

A high-resolution transmission microscopy study showed that the oxidation of Co nanoparticles deposited on montmorillonite resulted in the formation of nanoshells consisting of cobalt oxides and containing spherical voids. A linear dependence was found between the initial diameter of Co particles and the oxide shell thickness.

FORMATION OF MAGNETIC NANOCRYSTALS IN GERMANATE GLASSES DOPED WITH Fe AND Dy

I.S. Edel’man*, O.S. Ivanova*^,**, V.N. Zabluda*, R.D. Ivantsov*, G.V. Bondarenko*, V.I. Zaikovsky, S.A. Stepanov***
(*Kirensky Institute of Physics, Krasnoyarsk, Russia; ** Siberian Federal University, Krasnoyarsk, Russia; ***Vavilov State Optical Institute, All-Russia Research Center, St. Petersburg, Russia)

Nanotech. Russ., 3(11-12) (2008) pp. 722-728.

Magnetic nanocomposites were synthesized from germanate glasses doped with iron and dysprosium oxides at low concentrations. The formation of nanoparticles (~5–20 nm in size) in glasses subjected to heat treatment under different conditions was observed using high-resolution electron microscopy. Nanoparticles had a well-resolved crystal structure. X-ray fluorescence microprobe analysis showed that iron and dysprosium are concentrated in particles. The examination of the field dependences of the magneto-optical effect revealed magnetic ordering in particles. A comparison of the interplanar distances obtained using electron microdiffraction with those of the known iron oxide compounds did not lead to unambiguous results. Almost all specific features in the magnetic circular dichroism spectra of the glasses corresponded to the features previously observed in the spectra of garnet ferrites. On this basis, it was assumed that the particles formed in the germanate glasses have a distorted garnet structure.

STABILIZATION OF COPPER NANOPARTICLES IN Cu-ZSM-5

S.A.Yashnik, V.F. Anufrienko, V.I. Zaikovsky, V.A. Rogov, S.Ph. Ruzankin, Z.R. Ismagilov

Stud. Surf. Sci. Catal., 174A (2008) pp. 177-180.

The copper nanoparticles formed during reduction of Cu-ZSM-5 in hydrogen at temperature 150 – 400^oC were studied by UV-Vis spectroscopy and HRTEM. The plasmon resonance (PR) absorption at 1600017500 cm^-1 was used for copper nanoparticles identification. It was shown that the chain-like and square-plain copper-oxide clusters stabilized in Cu-ZSM-5 during its preparation are the precursors of copper nanoparticles 2-10 nm.

FORMATION AND EVOLUTION OF MAGNETIC NANOPARTICLES IN BORATE GLASS SIMULTANEOUSLY DOPED WITH Fe AND Mn OXIDES

J. Kliava*, I. Edelman**, O. Ivanova**, R. Ivantsov**, O. Bayukov**, E. Petrakovskaja**, V.I. Zaikovsky, I. Bruckental***, Y. Yeshurun***, S. Stepanov****
(*CPMOH, Universite Bordeaux, Talence Cedex, France; **Kirensky Institute of Physics, Krasnoyarsk, Russia; ***Department of Physics, Bar-Ilan University, Ramat-Gan, Israel; ****Vavilov State Optical Institute, St. Petersburg, Russia)

J. Appl. Phys., 104(10) (2008) 103917 (11 pp.).

Evolution of the phase state of paramagnetic additions at various stages of synthesis and subsequent thermal treatment of glasses of the system Al₂O₃– K₂O–B₂O₃ simultaneously doped with Fe₂O₃ and MnO is studied by means of a combination of experimental techniques: Faraday rotation (FR), electron magnetic resonance (EMR), transmission electron microscopy (TEM), Mossbauer spectroscopy, and magnetic measurements. Both FR and EMR show that magnetically ordered clusters occur already at the first stage of the glass preparation. In particular, for the ratio of the Fe andMn oxides in the charge close to 3:2, fine magnetic nanoparticles are formed with characteristics similar to those of manganese ferrite. By computer simulating the EMR spectra at variable temperatures, a superparamagnetic nature of these nanoparticles is confirmed and their mean diameter is estimated as approximately 3.2 nm. In the thermally treated glasses larger magnetic nanoparticles are formed, giving rise to FR spectra, characteristic of magnetically ordered systems, and the EMR spectra different from those in as-prepared glasses but also showing superparamagnetic narrowing. The Mossbauer spectroscopy corroborates the manganese ferrite structure of the nanoparticles and indicates their coexistence in the ferrimagnetic and superparamagnetic states. The TEM shows the presence of polydisperse nanoparticles on the background of the glass matrix, and electron diffraction of a selected region containing larger particles indicates a crystal structure close to that of MnFe₂O₄. Energy-dispersive atomic X-ray spectra confirm that the major part of Fe and Mn introduced to the glass composition is gathered in the particles, with the concentration ratio close to 2:1, characteristic of bulk MnFe₂O₄. Magnetic hysteresis loops of samples subjected to an additional thermal treatment demonstrate a strong increase in the coercive force, remnant magnetization, and high-field magnetic susceptibility with temperature decrease. The consistent results obtained using various techniques demonstrate that the formation of nanoparticles with characteristics close to those of MnFe₂O₄ confers to these glasses magnetic and magneto-optical properties typical of substances possessing magnetic order.

STRUCTURE OF HETEROGENEOUS STATES IN NANOCRYSTALLINE CoPd FILMS

E.M. Artem’ev*, V.I. Zaikovsky
(*Krasnoyarsk State University, Krasnoyarsk, Russia)

Bull. Russ. Academy Sci.: Phys., 72(10) (2008) pp. 1330-1332.

Thin films of equiatomic alloy CoPd have been produced by condensation at high substrate temperatures. The films obtained are characterized by microdiffraction patterns in the form of diffuse halo in the initial state. This is polymorphic martensitic transient state, formed during martensitic transformation of the low-temperature hcp phase to the high-temperature fcc phase. The metastable crystal structures arising in these alloy films are identified.

STRUCTURE OF GLASS SURFACES TREATED WITH THE NEW GLASS FROSTING PASTE SURFACE

O.N. Sidelnikova*, A.N. Salanov
(*Institute of Solid State Chemistry and Mechanochemistry, Novosibirsk, Russia)

Glass Technol., A, 49(4) (2008) pp. 179-182.

The paper is concerned with an investigation using scanning electron microscopy (SEM) of morphologies of frosted glass surfaces produced by using a new frosting paste. The new paste produces its effect by the physical process of surface ionic exchange and does not contain hydrofluoric acid or its compounds. The frosting process occurs at a temperature similar to 300^oC and is characterized by the appearance of a system of microblocks (similar to 50-150μm in size) and microcracks (similar to 100-200 nm wide) at the glass surface. The microblock boundaries are essentially smooth and the front surfaces of the blocks are smooth. The surface morphology after the metal deposition on frosted glass carried out by chemical reduction in solution is also demonstrated. In particular, silver deposition was carried out by the chemical reduction of Ag+ to metallic Ag using a silvering solution based on ammoniac silver complexes in the presence of glucose as a reducing agent. Micrographs of the surface structures obtained with chemical etching and Sand blasting are compared in this paper with those of the structures formed diving frosting by the new frosting paste. This comparison indicates that the glass surface morphology after glass frosting with the new glass frosting paste differs substantially from that obtained with well known chemical etching and sand blasting processes.

PROPERTIES OF A GLASS SURFACE MODIFIED BY A NEW FROSTING PASTE. DISPERSION OF LIGHT IN THE GLASS NEARSURFACE LAYER

O.N. Sidelnikova*, G.A. Pozdnyakov**, A.N. Salanov, E.A. Suprun, E.M. Pozdnyakov***
(*Institute of Solid State Chemistry and Mechanochemistry, Novosibirsk, Russia; **Khristianovich Institute of Theoretical and Applied Mechanics, Novosibirsk, Russia; ***Institute of Mining, Novosibirsk, Russia)

Glass Ceram., 11-12 (2008) pp. 384-389.

The results of an investigation of the optical properties of a 50-µm thick glass surface layer modified by a new frosting paste are presented. The action of the paste is based on a surface ion-exchange process that results in the formation of a system of microblocks and microcracks. The size distribution function of nonuniform scattering centers and the partial depolarization of the initially linearly polarized light are examined. It is noted that the light scattering characteristics of the modified glass layer are much different from the analogous characteristics of a glass surface which is frosted by chemical etching with a fluorine-containing etchant.

PERFORATED CENOSPHERE-SUPPORTED pH-SENSITIVE SPIN PROBES

E.V. Fomenko*, A.A. Bobko**^,***, A.N. Salanov, I.A. Kirilyuk****, I.A. Grigoriev****, V.V. Khramtsov***, A.G. Anshits*
(*Institute of Chemistry and Chemical Technology, Krasnoyarsk, Russia; **Institute of Chemical Kinetics and Combustion, Novosibirsk, Russia; ***Dorothy M. Davis Heart and Lung Research Institute, Ohio State University, Columbus, USA; ****Novosibirsk Institute of Organic Chemistry, Novosibirsk, Russia)

Russ. Chem. Bull., 57(3) (2008) pp. 493-498.

Porous supports with an accessible internal volume and a shell providing the diffusive migration of pH-sensitive spin probes were obtained for the first time from hollow aluminosilicate cenospheres isolated from the coal fly ash. Using the methods of scanning electron microscopy and electron spin resonance, the morphology of different porous cenosphere modifications and its influence on the diffusion of spin probes from the internal volume were studied. When supporting aqueous solutions of a radical, the characteristic diffusion time for the mesoporous structure of the support is longer by a factor of 3–5 than that for the macroporous structure. Ferrospinel in a content of 6 wt % do not virtually affect the diffusion rate of spin probes. A constant rate of radical migration of ~1μmol min⁻¹, determined by radical solubility in water, is achieved when a radical in the solid aggregate state is supported on the magnetic cenospheres.

ELECTRONIC FINGERPRINTING OF ADSORBED SPECIES BY MEANS OF THE SUBSTRATE CORE LEVEL EXCITATION

A.R. Cholach

In “Chemical Reactions on Surfaces”,
Eds. J.I. Duncan, A.B. Klein,
Nova Sci. Publishers, Inc., 2008, Ch. 8, pp. 263-287.

The conjugate electron excitation as a novel kind of electron-solid interaction was developed recently in model studies. This phenomenon enables to fingerprint the electronic valence state structure and thus to ascertain the chemical nature of adsorbed species of any complexity. It also gives potentiality to determine an exact location of adsorbed particle on the composite substrate surface. Disappearance potential spectra duly reveal another substrate electronic peculiarity such as surface and bulk plasmon excitations in addition to regular data on density of the vacant state structure. Besides, the comparison of experimental data and results of adequate quantum-chemical calculations can reveal the location of adsorbed atoms with respect to the top substrate layer, and provides reliable information on the bond nature of adsorbed species. Presented results on the whole evidence for the considerable unity of substrate and adsorbate electronic structures as an essential quality of adsorptive system.

ADVANCED POWER OF DISAPPEARANCE POTENTIAL SPECTROSCOPY IN THE ADSORBED SPECIES IDENTIFICATION

A.R. Cholach

Chem. Phys. Res. J., 2(3-4) (2008) ch. 2, 28 pp.

Advanced power of Disappearance Potential Spectroscopy for fundamental studies of adsorption and surface reaction mechanisms at the molecular level is highlighted. Electronic peculiarities of the adsorbed species can be characterized properly from an extended spectral structure processing due to following reasons. First, because of the pronounced sensitivity of this technique to precious few top sample layers those are exactly responsible for the course of surface reaction. Second, due to availability of the novel kind of electron-solid interaction, namely the conjugate electron excitation developed recently from the model studies. The latter phenomenon consists of ordinary substrate core level excitation accompanied by electron transition from the valence state of adsorbed particle to vacuum level. This is displayed experimentally as a set of spectral satellites localized by the respective ionization potential above the Fermi level of a given substrate component

CONTROL OF PARTICLE SIZE VIA CHEMICAL COMPOSITION: STRUCTURAL AND MAGNETIC CHARACTERIZATION OF Ni-Co ALLOY NANOPARTICLES ENCAPSULATED IN LAMELLAR MIXED OXIDES

K.A. Tarasov*, V.P. Isupov*, B.B. Bokhonov*, Y.A. Gaponov*, B.P. Tolochko*, M.M. Yulikov, V.F. Yudanov, A. Davidson**, P. Beaunier**, E. Marceau**, M. Che**
(*Institute of Solid State Chemistry and Mechanochemistry, Novosibirsk, Russia; **Laboratoire de Reactivite de Surface, Universite Pierre et Marie Curie, Paris, France)

Microporous Mesoporous Mater., 107(1-2) (2008) pp. 202-211.

Nanoparticles of Co-Ni alloys were prepared by thermal decomposition of layered double hydroxides (LDH) containing co-intercalated complexes of two metals. The precursor compounds [LiAl₂ (OH)₆] ₂{Ni_1-xCo_x(EDTA)}·4H₂O (where EDTA is ethylenediaminetetraacetate) obtained by anion exchange from [LiAl₂(OH)₆]Cl·1.5H₂O were treated at 450 °C in vacuum. The microstructure of the thermal products was studied using local (TEM, SAED, EDX) as well as integral (XRD, SAXS) methods. It was found that Ni-Co alloy nanoparticles are formed uniformly dispersed in the carbonized matrix of lamellar mixed oxides, and the increase of the relative cobalt content in Ni_1-xCO_x from x = 0 to 0.86 leads to gradual enlargement of the average alloy particle size from 9 to 16 nm. According to magnetic measurements by SQUID magnetometry and FMR, all alloys, except Ni_0.14Co_0.86, are superparamagnetic at room temperature. The results on particle size obtained by different techniques are in good agreement. The variation of nanoparticle size via chemical composition in alloys and the use of LDH intercalation matrices is a promising way to synthesize nanocomposites with target properties.

NOVEL CARBONYL COMPLEXES OF RUTHENIUM WITH α-SUBSTITUTED OXIME DERIVATIVES OF TERPENES

I.Yu. Shabalina, V.P. Kirin*, V.A. Maksakov*, A.V. Virovets*, A.V. Golovin, A.M. Agafontsev**, A.V. Tkachev**
(*Nikolaev Institute of Inorganic Chemistry, Novosibirsk, Russia; **Novosibirsk Institute of Organic Chemistry, Novosibirsk, Russia)

Russ. J. Coord. Chem., 34(4) (2008) pp. 286-294.

The reactions of Ru3(CO)12 with 1R,4S,6S-4dimethylamino-4,7,7-trimethylbicyclo[4.1.0]heptane3-one oxime (dimethylaminocaraneoxime) (I), 1R,4S,6S-4-methylamino-4,7,7-trimethylbicyclo [4.1.0]heptane-3-one oxime (methylaminocarane oxime) (II), and 1R, 2R,5R-2-benzylthio-2,6,6trimethylbicyclo[3.1.1]heptane-3-one oxime (benzylthiopinaneoxime) (III) were studied. The binuclear complex Ru₂ (CO)₄{μ-η³(O,N,X)-L}₂ was formed as the main product in every reaction, when Ru3(CO)12 was heated with terpenoid to 80°C. In the above complex, two terpene ligands are coordinated in the form of 'head-to tail' bridge by the oxime groups at a binuclear metal fragment Ru–Ru. The heteroatom of the second functional group of every bridging ligand (nitrogen of amino group in I and II, sulfur of the thio group in III) is additionally coordinated to the ruthenium atom to give the chelate five-membered ring. Also the reactions of terpenoids I, II, III with Ru₃(CO)₁₂ were performed at room temperature using Me₃NO. In this case, as in the thermal reactions, the main product was the binuclear complex. However, in the reactions of Ru₃(CO)₁₂ with I and II, the trinuclear clusters were isolated that readily transformed to binuclear complexes in a solution. The complexes synthesized can exist as two diastereomers due to their chiral metal core. However, in all the cases, only one diastereomer was isolated, which indicates stereospecific nature of the above reactions. The compounds obtained were characterized by IR, ¹H-, ¹³C{¹H}-, COSY, and HXCOBI-NMR spectroscopy, the specific optical rotation angles were measured. For the binuclear complexes with ligands I, III and for trinuclear cluster with ligand II, single crystals were obtained and studied by X-ray diffraction.

HIGH VOLUME SYNTHESIS OF SILICON NANOPOWDER BY ELECTRON BEAM ABLATION OF SILICON INGOT AT ATMOSPHERIC PRESSURE

S.P. Bardakhanov*, V.A. Volodin**, M.D. Efremov**, V.V. Cherepkov***, S.N. Fadeev***, A.I. Korchagin***, D.V. Marin**, M.G. Golkovskiy***, Yu.Yu. Tanashev, V.I. Lysenko*, A.V. Nomoev****, M.D. Buyantuev****, D. Sangaa*****
(*Khristianovich Institute of Theoretical and Applied Mechanics, Novosibirsk, Russia; **Institute of Semiconductor Physics, Novosibirsk, Russia; ***Budker Institute of Nuclear Physics, Novosibirsk, Russia; ****Buryatian State University, Ulan Ude, Russia; *****Institute of Physics and Technology of Mongolian Academy of Sciences, Ulaanbaatar, Mongolia)

Jpn. J. Appl. Phys., 47(9) (2008) pp. 7019–7022.

The evaporation of high purity silicon ingot was performed in Ar, N₂, and air atmospheres using a power electron accelerator. The obtained powders with primary particle sizes of 10-500 nm were investigated using Brunauer-Emmett-Teller analysis (BET), X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), photoluminescence measurement, and Raman spectroscopy. The structure and photoluminescence properties of Si(Ar) nanopowder obtained at a large quenching rate differ substantially from those of Si(Ar) and Si(N₂) obtained at a smaller quenching rate. Photoluminescence peaks in the visible region of the spectrum are detected at room temperature for the Si(Ar) nanopowders.

STOICHIOGRAPHY AND CHEMICAL METHODS OF PHASE ANALYSIS OF MULTIELEMENT MULTIPHASE SUBSTANCES AND MATERIALS

V.V. Malakhov, I.G. Vasilyeva*
(*Nikolaev Institute of Inorganic Chemistry, Novosibirsk, Russia)

Russ. Chem. Rev., 77(4) (2008) pp. 351-372.

The problems and achievements in the determination of the phase composition of multielement multiphase inorganic solid substances are considered. The problems of theory, methodology and practical use of two chemical methods of phase analysis, viz., selective dissolution and reference-free stoichiographic dissolution are discussed. The unique potential of stoichiography and differential dissolution method, which allows one to overcome many limitations and difficulties typical of modern phase analysis techniques, are demonstrated. Examples of using differential dissolution for the phase analysis of diverse substances and functional materials are given.

LASER-INDUCED LUMINESCENCE OF MODEL Fe/Al2O3 AND Cr/Al2O3 CATALYSTS

V.N. Snytnikov, V.O. Stoyanovsky, T.V. Larina, O.P. Krivoruchko, V.A. Ushakov, V.N. Parmon

Kinet. Catal., 49(2) (2008) pp. 291-298.

The laser-induced luminescence of Cr³⁺ impurity ions in model Fe/Al₂O₃ and Cr/Al₂O₃ catalysts with different calcination temperatures was studied. It was found that an additional luminescence band at 770 nm appeared in the luminescence spectra of low-temperature samples as a result of the interaction of octahedrally coordinated Cr³⁺ ions with Fe³⁺ impurity ions. In the θ-Al₂O₃ phase with a concentration of Cr³⁺ ions higher than 0.1 wt %, the interaction of the Cr³⁺- Cr³⁺ ion pairs in the immediate surroundings resulted in the appearance of N θ lines due to the splitting of R θ lines. The differences of these lines from the Nα lines ofα-Al₂O₃ were related to the individuality of the crystal lattice of the θ phase and the coordination of Cr³⁺ impurity ions in the immediate surroundings, which is different from that in the a phase. Based on the laser-induced luminescence spectroscopic data, it was found that regions with a local Cr³⁺ concentration higher than the average Cr³⁺ concentration in the bulk of a catalyst by one order of magnitude were formed in theα-Al₂O₃-Fe₂O₃ system with the bulk Fe and Cr concentrations of 2.5 and 0.04 wt %, respectively, which was calcined at 1220^oC, as a result of the diffusion of chromium and iron ions.

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