23 ноября 2023
Памяти Р.А. Буянова
The scientific cooperation of the Boreskov Institute of Catalysis with the catalytic communities from various countries is effected in accordance with various forms
of cooperation: conducting joint seminars on catalysis, exchanging the information and appropriate materials, exchanging research fellows, visiting scientific centers,
and participating in congresses and symposia on theoretical and applied catalysis.
According to research programs, projects and grants, the fundamentals of catalysis are studied jointly with researchers from various universities, institutions,
research laboratories and companies. BIC collaborates fruitfully on a commercial basis with the leading companies from more than 20 countries, sells licenses,
know-how and performs research projects according to client requests.
Academician Valentin N. Parmon is the Russian representative in the European Federation of Catalytic Societies (EFCATS), Member of the International Association
of the Catalysis Societies (IACS).
Australia |
1 |
Greece |
2 |
Netherlands |
9 |
Austria |
4 |
Hungary |
1 |
Poland |
5 |
Belarus |
8 |
India |
4 |
Republic of Korea |
16 |
Belgium |
11 |
Ireland |
1 |
Slovenia |
1 |
Bulgaria |
7 |
Israel |
4 |
Spain |
4 |
Canada |
2 |
Italy |
16 |
Switzerland |
2 |
China |
25 |
Japan |
12 |
Sweden |
1 |
Czechia |
1 |
Kazakhstan |
3 |
Taiwan |
1 |
Denmark |
1 |
Lithuania |
2 |
Thailand |
1 |
Egypt |
2 |
Malta |
50 |
Tunisia |
1 |
Finland |
8 |
Mexico |
1 |
Ukraine |
6 |
France |
19 |
Mongolia |
1 |
UK |
5 |
Germany |
33 |
Montenegro |
1 |
USA |
8 |
Visits of foreign specialists to the Boreskov Institute of Catalysis in 2008
Belarus |
2 |
Hungary |
1 |
Serbia and Montenegro |
2 |
Bulgaria |
1 |
India |
3 |
Spain |
1 |
China |
7 |
Japan |
4 |
Republic of Korea |
6 |
Czechia |
1 |
Kazakhstan |
1 |
Ukraine |
3 |
France |
11 |
Netherlands |
6 |
UK |
3 |
Germany |
5 |
Saudi Arabia |
1 |
USA |
14 |
ITALY
The cooperation in the frame of the agreement between Russian Academy of Sciences (RAS) and National Council on the Scientific Research of Italy with The Istituto di Tecnologie Avanzate per l'Energia "Nicola Giordano"(CNR Institute of Advanced Energy Technologies "Nicola Giordano"), Messina on the Project “Materials with Enhanced Properties for Energy Conversionâ€. Coordinators: Prof. Yu. Aristov (BIC) and
Prof. G. Restuccia (Istituto di Tecnologie Avanzate per l'Energia "Nicola Giordano").
FRANCE
According to the agreement between RAS and CNRS BIC collaborates with the Institute de Recherches sur la Catalyse (Research Institute on Catalysis), Villeurbanne in the frame of the Russian-French European associated Laboratory on Catalysis headed by Acad. V. Parmon and Dr. M. Lacroix. The Laboratory was established by an agreement signed December 6, 2004 in Moscow by RAS and CNRS. Four areas of research were identified:
INDIA
In the frame of Indo-Russian Integrated Long Term Programme of cooperation in science and technology (ILTP) BIC collaborates with:
Coordinators on the Program "Catalysis" are Acad. V. Parmon and Dr. S. Sivaram.
GERMANY
The cooperation in the frame of the agreement between RAS and German Scientific Research Society (GSRS) with Fritz-Haber-Institut der Max-Planck-Gesellschaft, Berlin on the 27 Project "Development of in situ Methods for Study of Solid Surfaces" . Coordinators: Prof. V. Bukhtiyarov (BIC) and Prof. R. Schlögl (Fritz-Haber-Institut der MPG).
JAPAN
Bilateral agreement BIC - Research Laboratory for Nuclear Reactors, Tokyo Institute of Technology, on the Project "Adsorption and Chemical Reactions for Heat Transformation". Coordinators: Prof. Yu. Aristov (BIC), Prof. Y. Kato (Research Laboratory for Nuclear Reactors)
CHINA
The cooperation in the frame of Associated Research Laboratory which was established by an agreement signed December 4, 2004 by the
Boreskov Institute of Catalysis and Heilongjiang University, Harbin. Chief Executive officers of Laboratory are:
Prof. V. Bukhtiyarov (BIC) and Fu Hong-Gang (Heilongjiang University). Project "Synthesis and Modification of
ZSM-12 Zeolites. Zeolite ZSM-12 in Reaction of Naphthalene Alkylation with Methanol".
Coordinators: Prof. Wu Wei (Heilongjiang University), Prof. G. Echevsky (BIC).
KOREA
In the frame of the agreement between RAS and Korea Science and Engineering Foundation (KOSEF) BIC cooperates with Korea Institute of Science and Technology, Seoul,
Korea.
COOPERATION IN THE FRAME OF PROJECTS FINANCED BY INTERNATIONAL FOUNDATIONS
INTAS - SB RAS Supported Project
Electromagnetic Response Properties of Carbon Onions and Carbon Onion-Based Composites
Project Coordinator:
Dr. Ph. Lambin, Facultes Universitaires Notre-Dame de la Paix, Namur, Belgium
Participants:
Belarus State University, Minsk, Belarus; University of Joensuu, Finland; Institute for Technical
Physics and Materials Science, Budapest, Hungary; The Boreskov Institute of Catalysis,
Novosibirsk, Russia (Dr. V. Kuznetsov), Nikolaev Institute of Inorganic Chemistry,
Novosibirsk, Russia.
CRDF Project
Carbon Nanoreactor for Solid-State Synthesis of Novel Nanoscale Materials Based on
Nanocrystalline Oxides
Project Coordinators:
Prof. A. Volodin, The Boreskov Institute of Catalysis, Novosibirsk, Russia
Prof. K.J. Klabunde, Kansas State University, Manhattan, Kansas, USA.
EUROPEAN COMMUNITY SIXTH FRAMEWORK PROGRAM
I. International Partnership for a Hydrogen Economy for Generation of New Ionomer Membranes
Coordinator: Dr. R. Mallant, Energy Research Centre of The Netherlands, Petten, The Netherlands
Partners:
Daimler Chrysler; FuMA-Tech GmbH; CNRS Montpellier; Dohgyue Chenzhou New Materials Company; Shanghai Jiao Tong University, Shanghai, China; The Boreskov Institute of Catalysis, Novosibirsk, Russia (Prof. V. Bukhtiyarov).
II. Co-Processing of Upgraded Bio-Liquids in Standard Refinery Units
Coordinator: Dr. Y. Solantausta, VTT Processes, Espoo, Finland
Partners:
Rijksuniversiteit Groningen, The Netherlands; The Boreskov Institute of Catalysis, Novosibirsk, Russia (Prof. V. Kirillov); Uhde Hochdrucktechnik GmbH, Germany; BTG Biomass Technology Group BV, The Netherlands; University of Twente, The Netherlands; STFI-PACKFORSK AG, Sweden; Institute of Wood Chemistry, Hamburg, Germany; Slovenian Institute of Chemistry, Slovenia; Arkema SA, France; Helsinki University of Technology, Finland; ALMA Consulting Group SAS, France; Centre National de la Recherche Scientifique, France; Chimar Hellas SA, Greece; Albermarle Catalysts Company BV, The Netherlands; Metabolic Explorer, France; Shell Global Solutions International, The Netherlands.
III. Non-Noble Catalysts for Proton Exchange Membrane Fuel Cell Anodes
Coordinator:
Dr. G. Tsotridis, Institute for Energy, Joint Research Centre, Petten, The Netherlands
Partners:
Technical University of Denmark, Lyngby, Denmark; The Boreskov Institute of Catalysis, Novosibirsk, Russia (Acad. V. Parmon, Dr. O. Pestunova); Southampton University, UK; Technical University of Munich, Germany; Bavarian Center for Applied Energy Research; Umicore, AG & Co KG, Germany.
IV. Novel Materials for Silicate-Based Fuel Cells
Coordinator: Dr. Ch. Arguirusis, Technische Universität Clausthal, Clausthal, Germany
Partners:
University of Aveiro, Aveiro, Portugal; Foundation of Research and Technology Hellas, Greece; Katholieke University of Leuven, Belgium; Max-Plank Institute of Colloids and Interfaces, Munchen, Germany; The Boreskov Institute of Catalysis, Novosibirsk, Russia (Prof. V. Sadykov); Ceramics and Refractories Technological Development Company, Greece; Ceramiques Techniques et Industrielles, France.
EUROPEAN COMMUNITY SEVENTH FRAMEWORK PROGRAM
Reforming of Crude Glycerine in Supercritical Water to Produce Methanol for Re-Use in Biodiesel Plants
Coordinator: J. Vos, BTG BiomassTechnology Group BV, The Netherlands
Partners:
Acciona Servicios Urbanos, Spain; The Boreskov Institute of Catalysis, Novosibirsk, Russia (Prof. V. Kirillov); Rijksuniversiteit Groningen, The Netherlands; University of Maribor, Slovenia; UHDE High Pressure Technologies GmbH, Germany; SPARQLE International BV, The Netherlands.
NATO PROGRAMME: SCIENCE FOR PEACE
I. Solid Oxide Fuel Cells for Energy Security
NATO Country Project Director:
Prof. N. Orlovskaya, Drexel University, Philadelphia, USA
Partner Country Project Director:
Prof. O. Vasiliev, Frantcevych Institute for Problems of Material Science, Kiev, Ukraine
Project Co-Directors:
Prof. V. Sadykov, The Boreskov Institute of Catalysis, Novosibirsk, Russia
Prof. J. Irvine, University of St. Andrews, St. Andrews, UK|
Prof. N. Sammes, University of Connecticut, Storrs, USA
Prof. R. Hasanov, Azerbaijan State Oil Academy, Baku, Azerbaijan
Dr. A. Schokin, State Committee for Energy Saving of Ukraine, Kiev, Ukraine
Prof. John Kilner, Imperial College, London, UK.
II. Mixed Conducting Membranes for Partial Oxidation of Natural Gas to Synthesis Gas
NATO Country Project Director:
Prof. J. Frade, Departamento de Engenharia Cerâmica e do Vidro, Universidade de Aveiro, Aveiro, Portugal
Partner Country Project Director:
Dr. V. Kharton, Institute of Physicochemical Problems, Belarus State University, Minsk, Belarus
Project Co-Directors:
Dr. J. Irvine, School of Chemistry, University of St. Andreas, Scotland, UK
Dr. T. Norby, SMN, Universitetet i Oslo, Oslo, Norway
Dr. J. Jurado, Instituto de Cerámica y Vidrio, CSIC, Madrid, Spain
Prof. V. Sobyanin, The Boreskov Institute of Catalysis, Novosibirsk, Russia
Prof. V. Kozhevnikov, Institute of Solid State Chemistry, Yekaterinburg, Russia
Dr. L. Boginsky, Institute for Personal Development and Staff Retraining in New Areas of Techniques, Technologies
and Economics of the Belarus Ministry of Education, Minsk, Belarus.
III. Development of Electromagnetic Wave Absorbing Coatings Based on Carbon Onions
NATO Country Project Director:
Prof. Ph. Lambin, Facultés Universitaires Notre-Dame de la Paix, Namur, Belgium
Partner Country Project Director:
Dr. O. Shenderova, International Technology Center Raleigh, USA
Project Co-Directors:
Dr. V. Kuznetsov, The Boreskov Institute of Catalysis, Novosibirsk, Russia
Dr. I. Larionova, Real-Dzerzhinsk Ltd., Dzerzhinsk, Russia
Dr. S. Maksimenko, Belarus State University, Minsk, Belarus
Prof. A. Okotrub, Nikolaev Institute of Inorganic Chemistry, Novosibirsk, Russia
NATO PROGRAMME: SCIENCE FOR PEACE AND SECURITY
Capture and Decontamination of Chemical & Biological Agents by Novel Catalysts and Millisecond Jet Reactors
Project Coordinator from a NATO Country:
Prof. P. Smirniotis, University of Cincinnaty, Cincinnaty, USA
Project Coordinator from a Partner Country:
Prof. A. Vorontsov, The Boreskov Institute of Catalysis, Novosibirsk, Russia.
INTERNATIONAL SCIENCE AND TECHNOLOGY CENTER (ISTC)
I. Development of Catalysts and Reactors for Syn-Gas Production from Diesel Fuel and for Selective NO>x Reduction with Syn-Gas in Diesel Exhausts
Project Manager from BIC Prof. V. KirillovII. Development of High-Performance Oxygen-Containing Membranes and Compact Syn-Gas Generators on Their Base
Project Manager from BIC Prof. V. SadykovIII. Synthesis and Investigation of the Metal Oxide Catalysts for Photocatalytic Degradation of Harmful Gases Resulted from Terrorist Acts and Man-Caused Catastrophes
Project Manager from BIC Prof. A. VorontsovIV. Catalytic Production of SO3 for Conditioning of Electrostatic Precipitators Using in Russia and the Newly Independent States (NIS)
Project Manager from BIC Prof. A. ZagoruikoV. Development of an Integrated Separator for Direct Reforming of Hydrocarbons in High-Temperature Fuel Cells
Project Manager from BIC Prof. Z. IsmagilovVI. Synthesis, Formation and Modification of (In)Organic Nanoparticles in Supercritical Fundamentals and Applications
Project Manager from BIC Prof. V. Anikeev.Страницы 1 - 1 из 14
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CLUSTER MODEL DFT STUDY OF CO ADSORPTION TO GALLIUM IONS IN Ga/HZSM-5
G.M. Zhidomirov, A.A. Shubin, M.A. Milov, V.B. Kazansky*, R.A. van Santen**, E.J.M. Hensen**
(*Zelinsky Institute of Organic Chemistry, Moscow, Russia; **Eindhoven University of Technology, Eindhoven, The Netherlands)
J. Phys. Chem. C, 112(9) (2008) pp. 3321-3326.
Cluster model DFT calculations of CO adsorption on various possible forms of gallium in Ga/HZSM-5 zeolites have been performed. CO was found to only weakly interact with Ga+, (GaO)+, and (Ga(OH)2-nHn)+ (n = 1, 2) cationic clusters. The resulting shifts of the CO stretching frequency (ΔνCO) are only very small. On the other hand, CO coordination to small mononuclear and binuclear Ga3+ hydride/hydroxide/oxide species results in positive shifts in the stretching frequency in the range ΔνCO-1. Larger shifts (ΔνCO = 70-90 cm-1) are associated with CO coordination to Ga ions at the corners of small three-dimensional Ga-oxide clusters. The experimentally observed changes in the infrared spectrum of adsorbed CO over Ga/HZSM-5 zeolites upon reductive and oxidative treatments are interpreted with these insights. Possibilities for the formation of such polynuclear oxide species in the zeolite micropore space are discussed. On the basis of recent literature insights, it is suggested that large shifts derive from CO coordination to oligomeric Ga cationic complexes stabilized by the negative zeolite charge.
NON-LOCALIZED CHARGE COMPENSATION IN ZEOLITES: A PERIODIC DFT STUDY OF CATIONIC GALLIUM-OXIDE CLUSTERS IN MORDENITE
E.A. Pidko*, E.J.M. Hensen*, G.M. Zhidomirov, R.A. van Santen*
(*Eindhoven University of Technology, Eindhoven, The Netherlands)
J. Catal., 255(2) (2008) pp. 139-143.
Periodic DFT calculations show that stability of binuclear cationic gallium-oxo clusters in high-silica zeolites is mainly controlled by the favorable geometrical environment of the Ga3+ ions, whereas the effect of the direct interaction with the charge-compensating framework anionic sites is less important. Extraframework cyclic Ga2O2+2 cations are shown to be active for light alkane dehydrogenation.
ADSORPTION PROPERTIES OF OXIDIZED GALLIUM-MODIFIED ZEOLITE ZSM-5 FROM DIFFUSE-REFLECTANCE IR-SPECTROSCOPIC AND QUANTUM-CHEMICAL DATA: II. INTERACTION WITH CARBON MONOXIDE AND WATER
I.R. Subbotina*, N.A. Sokolova*, I.V. Kuza'min*, A.A. Shubin, G.M. Zhidomirov, V.B. Kazanskii*
(*Zelinsky Institute of Organic Chemistry, Moscow, Russia)
Kinet. Catal., 49(1) (2008) pp. 149-155.
Diffuse-reflectance IR spectroscopy was used to study the adsorption and subsequent high-temperature transformations of water and carbon monoxide molecules on the oxidation-treated gallium-modified zeolite Ga/HZSM-5. The results were correlated with the corresponding quantum-chemical calculation data. Usually, it is thought that the oxo ions [Ga=O]+ are formed in the oxidation of Ga/HZSM-5. Based on the experimental and calculated data, the possible reactions of the gallium oxo ions with the above molecules are considered. The oxo ions were found highly reactive, and it is likely that polynuclear gallium oxide nanoclusters were formed in the oxidation of the gallium-substituted zeolite Ga/HZSM-5. The Ga+ ions, which appeared in the course of Ga/HZSM-5 reduction, were partially oxidized by water at 573 K; in turn, this could initiate the formation of polynuclear nanoclusters. It was found that ~25% of the Ga+ ions were oxidized in the interaction with water to liberate molecular hydrogen. The thermal reduction of a nitrous oxideaˆ“preoxidized Ga/HZSM-5 sample with carbon monoxide was studied, and a conclusion on dissimilar states of oxygen bound to gallium was drawn.
A THEORETICAL INVESTIGATION OF THE ADSORPTION SURFACE SITES OF THE ACTIVATED MgCl2
D.A. Trubitsyn, V.A. Zakharov, I.I. Zakharov
J. Mol. Catal. A: Chem., 270(1-2) (2007) pp. 164-170.
The adsorption of carbon monoxide on activated MgCl2 has been investigated within DFT using different models of the MgCl2 surface. All the models were Mg6Cl10 clusters with two saturating OH groups. It has been found that the adsorption sites within the models based on the geometry of the ideal MgCl2 crystal are stronger than they are in the experiment. It has also been found that relaxed clusters based on the geometry of the relaxed MgCl2 surface present more accurate models of the MgCl2 surface and account the relaxation effects properly. IR spectra of carbon monoxide bounded to three different adsorption sites calculated within relaxed clusters approximation is in excellent agreement with the experimental data. Such an agreement allows to conclude that adsorption sites of the activated MgCl2 surface in general are 3-, 4-and 5-fold Mg atoms and the structure of these sites follows the structure of corresponded relaxed MgCl2 crystallographic faces.
SIZE-DEPENDENCE OF ADSORPTION PROPERTIES OF METAL NANOPARTICLES: A DENSITY FUNCTIONAL STUDY ON Pd NANOCLUSTERS
I.V. Yudanov, M. Metzner*, A. Genest*, N. Rösch*
(*Technische Universität München, Garching, Germany)
J. Phys. Chem. C, 112(51) (2008) pp. 20269aˆ“20275.
Interatomic distances in metal nanoparticles are reduced from their values in the bulk. It was studied computationally how this size-dependent geometry change (from the bulk) relates to the size-dependence of other properties of large metal clusters, including their reactivity. For this purpose, using an all-electron scalar-relativistic density-functional approach, structures and binding energies for the example of CO adsorption on 3-fold hollow sites at the center of (111) facets of cuboctahedral nanoscale clusters Pdn (n = 55-260) were calculated. The average nearest-neighbor Pd-Pd distance of optimized structures is 4-7 pm (2-3%) shorter than the extrapolated limit of the lateral distance within an infinite (111) surface. In consequence, the energy of CO adsorption on a cluster of aˆ“100 atoms is aˆ“15 kJ mol-1 smaller than the extrapolated limit. On the basis of these results, a strategy was suggested for modeling particles of larger size, e.g. of 1000 atoms and more, with the help of smaller model particles of up to aˆ“300 atoms where one keeps the core of a model cluster fixed at the bulk structure and restricts the structure optimization to the outermost shell of cluster atoms.
HOW THE C-O BOND BREAKS DURING METHANOL DECOMPOSITION ON NANOCRYSTALLITES OF PALLADIUM CATALYSTS
I.V. Yudanov, A.V. Matveev, K.M. Neyman*, N. Rösch**
(*Universitat de Barcelona, Barcelona, Spain; **Technische Universität München, Garching, Germany)
J. Amer. Chem. Soc., 130(29) (2008) pp. 9342-9352.
Experimental findings imply that edge sites (and other defects) on Pd nanocrystallites exposing mainly (111) facets in supported model catalysts are crucial for catalyst modification via deposition of CHx (x=0-3) byproducts of methanol decomposition. To explore this problem computationally, the authors applied recently developed approach to model realistically metal catalyst particles as moderately large three-dimensional crystallites. The first results of this advanced approach are presented here where the authors comprehensively quantify the reactivity of a metal catalyst in an important chemical process. In particular, to unravel the mechanism of how CHx species are formed, density functional calculations of C-O bond scission in methanol and various dehydrogenated intermediates (CH3O, CH2OH, CH2O, CHO, CO), deposited on the cuboctahedron model particle Pd79, were carried out. The lowest activation barriers, ~130 kJ mol-1, of C-O bond breaking and the most favorable thermodynamics for the adsorbed species CH3O and CH2OH which feature a C-O single bond were calculated. In contrast, dissociation of adsorbed CO was characterized as negligibly slow. From the computational result that the decomposition products CH3 and CH2 preferentially adsorb at edge sites of nanoparticles, the authors rationalize experimental data on catalyst poisoning.
HYDROGEN ACTIVATION ON SILVER: A COMPUTATIONAL STUDY ON SURFACE AND SUBSURFACE OXYGEN SPECIES
A.B. Mohammad*, I.V. Yudanov, K.H. Lim**, K.M. Neyman***, N. Rösch*
(*Technische Universität München, Garching, Germany; **Nanyang Technological University, Singapore; ***Universitat de Barcelona, Barcelona, Spain) J. Phys.
Chem. C, 112(5) (2008) pp. 1628-1635.
Clean silver is known to be inert toward H2 dissociation. Nevertheless, silver catalysts recently have been found to exhibit a noteworthy selectivity in the hydrogenation of unsaturated aldehydes to unsaturated alcohols. Experimental studies indicate that pretreatment in oxygen atmosphere activates the catalyst. To examine the role of oxygen in activation of hydrogenation catalysts, a density functional study on periodic slab models of H2 dissociation at various oxygen species on silver surfaces, including subsurface oxygen, were carried out. According to calculations all oxygen forms under scrutiny promote dissociation of molecular hydrogen. With hydrogenation reactions in mind, the authors discuss a mechanism according to which an oxygen species, before it desorbs as a water molecule, produces one or two active hydrogen atoms on a metal terrace.
SPIN STATES OF IRON-NITROSYL ADSORPTION COMPLEXES FORMED IN Fe-ZSM5 ZEOLITES
S.E. Malykhin, A.M. Volodin, G.M. Zhidomirov
Appl. Magnet. Resonance, 33(1-2) (2008) pp. 153-166.
The capability of extra-framework monoiron sites to adsorb up to three NO molecules has been proven by quantum chemical calculations. Spin states of iron-nitrosyl adsorption complexes formed in Fe-ZSM5 zeolites have been found. For an initial iron site with S = 2, successive adsorption of one, two and three NO molecules changes S to 3/2, 1 and 1/2, respectively. Thus, the electron paramagnetic resonance (EPR) S = 1/2 signal observed after NO adsorption on the Fe-ZSM5 catalyst may be assigned to the Fe2+(NO)3 species. Some peculiarities of the S = 1/2 EPR spectra obtained for iron-nitrosyl species in zeolites are discussed.
ESEEM MEASUREMENTS OF LOCAL WATER CONCENTRATION IN D2O-CONTAINING SPIN-LABELED SYSTEMS
A.D. Milov*, R.I. Samoilova*, A.A. Shubin, Yu.A. Grishin*, S.A. Dzuba*
(*Institute of Chemical Kinetics and Combustion, Novosibirsk, Russia)
Appl. Magn. Reson., 35 (2008) pp. 73-94.
To calibrate electron spin echo envelope modulation (ESEEM) amplitudes with the respect to the deuterium water content in spin-labeled biological systems, ESEEM of nitroxide TEMPO has been studied in frozen glassy D2O-dimethylsulfoxide mixtures of different composition. The interaction between the unpaired electron of nitroxide and the deuterium nuclei manifests itself in a cosine Fourier transform spectrum as the sum of a narrow line with the doublet quadrupole splitting and of a broad one. The narrow line arises from interaction with distant deuterium nuclei, the broad one arises from interaction with nearby nuclei belonging to nitroxide-water molecule complexes. The dependence on water concentration was found to be nonlinear for the intensity of the narrow line and close to linear for the intensity of the quadrupole doublet. Therefore, the intensity of the quadrupole doublet is suggested as a measure of concentration of free water around a spin label in biological objects. Fourier transform line shape was theoretically simulated for different model distributions of water molecules around the spin label. Simulations confirm the linear dependence of the quadrupole doublet intensity on water concentration seen in the experiment. The suggested approach was applied to analyze data for spin-labeled dipalmitoylphosphatidylcholine (DPPC) and DPPC-cholesterol D2O-hydrated model membranes. The concentration of free water near the spin-labeled fourth carbon atom along the lipid chain was estimated as 5.2 and 7.2 M for DPPC and DPPC-cholesterol membranes, respectively.
ELECTRONIC STRUCTURE AND CHARGE TRANSPORT PROPERTIES OF AMORPHOUS Ta2O5 FILMS
V.A. Shvets*, V.Sh. Aliev*, D.V. Gritsenko*, S.S. Shaimeev*, E.V. Fedosenko*, S.V. Rykhlitski*, V.V. Atuchin*, V.A. Gritsenko*, V.M. Tapilin, H. Wong**
(*Institute of Semiconductor Physics, Novosibirsk, Russia; **City University of Hong Kong, Kowloon, Hong Kong)
J. Non-Cryst. Solids, 354(26) (2008) pp. 3025-3033.
Amorphous Ta2O5 films were deposited by sputtering Ta onto silicon substrates with reactive ion beam. Electron energy loss spectroscopy measurements on the film found that the plasma oscillation energy is 23.1 eV. The refractive index and the extinction coefficient were measured with spectroscopic ellipsometry over the spectral range of 1.9-4.9 eV. The optical band gap is found to be 4.2A±0.05 eV. The valence band consists of three bands separated by ionic gaps. The values of electron effective masses were estimated with ab initio quantum chemical calculation. Experiments on injection of minority carriers from silicon into oxide were also conducted and the authors found that the electron component of conduction current governed by the electron current in the amorphous Ta2O5.
ON THE MECHANISM OF MECHANOCHEMICAL DIMERIZATION OF ANTHRACENE. QUANTUM-CHEMICAL CALCULATION OF THE ELECTRONIC STRUCTURE OF ANTHRACENE AND ITS DIMER
V.M. Tapilin, N.N. Bulgakov, A.P. Chupakhin*, A.A. Politov*,**
(*Novosibirsk State University, Novosibirsk, Russia; **Institute of Solid State Chemistry and Mechanochemistry, Novosibirsk, Russia)
J. Struct. Chem., 49(4) (2008) pp. 581-586.
The electronic structure of anthracene, its dimer, and intermediate structures composed of two anthracene molecules were calculated in the density functional theory. The calculated potential barrier to anthracene dimerization is ~55 kcal/mol; the dissociation barrier is ~45 kcal/mol. The pressure required for the reaction to reach the transition state and acting on the anthracene crystal is ~60 kbar. Lower pressures, ~10 kbar, are required for molecules to approach each other to distances of ~3 A…, at which tunnel dimerization is possible for photoexcited molecules.
NEW APPROACH TO THE CORRELATION PROBLEM: ELECTRON INTERACTION POTENTIAL AS A VARIABLE IN SOLVING THE MANY-PARTICLE SCHRÖDINGER EQUATION
V.M. Tapilin
J. Struct. Chem., 49(3) (2008) pp. 387-394.
The many-electron wave function is represented as the product of the wave function of the independent particles and the function that depends only on the value of the interelectron interaction potential. The function defines the electron correlation effects; a standard linear differential equation was derived to define the function. The equation depends on the functions of independent particles; a generalization of the Hartree-Fock equations including electron correlation was obtained for these functions. The total energy calculation of two-electron ions shows that even solving an ordinary differential equation for the function of independent particles represented by the functions of noninteracting electrons leads to higher accuracy than the one achieved in the Hartree-Fock theory.
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