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Peculiarities of Ethylene Polymerization Reactions with Bis(imino)pyridyl Complexes of CoCl_(2) and FeCl_(2)

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Chinese Journal of Polymer Science 2024年第4期42卷 492-500页

作者： Laura A.Rishina Yury V.Kissin Svetlana S.Lalayan Artem A.Antonov Vadim G.Krasheninnikov Alexander A.Gulin N.N.semenov federal research Center for chemical physics Russian Academy of Sciences4 Kosygin St.Moscow119991Russia Department of Chemistry and chemical Biology RutgersThe State University of New Jersey123 Bevier Rd.PiscatawayNJ08854USA Boreskov Institute of Catalysis Russian Academy of Sciences5 Lavrentieva Prosp.Novosibirsk630090Russia

The article describes ethylene polymerization reactions with transition metal catalysts based on complexes of CoCl_(2) and FeCl_(2) with an N,N,N-tridentate ligand 2,6-bis[1-(2,6-dimethylphenylimino)ethyl]pyridine. The complexes are converted into polymerization catalysts by reacting them either with polymethylalumoxane (MAO) or with a combination of Al(C2H5)2Cl and Mg(C4H9)2 at an [Al]:[Mg] ratio of ~3. Both MAO-activated complexes readily polymerize ethylene at 35 ℃ with the formation of linear, low molecular weight polymers with a narrow molecular weight distribution. The same complexes, when activated with the Al(C2H5)2Cl-Mg(C4H9)2 combination, form multi-center catalysts and generate polyethylenes with a broad molecular weight distribution.

关键词： Ethylene polymerization Bis(imino)pyridyl complexes of CoCl_(2)and FeCl_(2) Molecular-weight distribution Polymer chain structure

Quantum algorithms for matrix operations and linear systems of equations

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Communications in Theoretical physics 2024年第3期76卷 100-112页

作者： Wentao Qi Alexandr I Zenchuk Asutosh Kumar Junde Wu School of Mathematical Sciences Zhejiang UniversityHangzhou 310027China federal research Center of Problems of chemical physics and Medicinal Chemistry RAS ChernogolovkaRussia P.G.Department of physics Gaya CollegeMagadh UniversityRampurGaya 823001India Harish-Chandra research Institute HBNIChhatnag RoadJhunsiPrayagraj 211019India Vaidic and Modern physics research centre Bhagal BhimBhinmalJalore 343029India

Fundamental matrix operations and solving linear systems of equations are ubiquitous in scientific *** the‘sender-receiver’model,we propose quantum algorithms for matrix operations such as matrix-vector product,matrix-matrix product,the sum of two matrices,and the calculation of determinant and inverse *** encode the matrix entries into the probability amplitudes of the pure initial states of *** applying proper unitary transformation to the complete quantum system,the desired result can be found in certain blocks of the receiver’s density *** quantum protocols can be used as subroutines in other quantum ***,we present an alternative quantum algorithm for solving linear systems of equations.

关键词： matrix operation systems of linear equations ‘sender-receiver’quantum computation model quantum algorithm

Oxidized organic molecules in the tropical free troposphere over Amazonia

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National Science Review 2024年第1期11卷 174-184页

作者： Qiaozhi Zha Diego Aliaga Radovan Krejci Victoria A.Sinclair Cheng Wu Giancarlo Ciarelli Wiebke Scholz Liine Heikkinen Eva Partoll Yvette Gramlich Wei Huang Markus Leiminger Joonas Enroth Otso Per?kyl? Runlong Cai Xuemeng Chen Alkuin Maximilian Koenig Fernando Velarde Isabel Moreno Tuukka Pet?j? Paulo Artaxo Paolo Laj Armin Hansel Samara Carbone Markku Kulmala Marcos Andrade Douglas Worsnop Claudia Mohr Federico Bianchi Institute for Atmospheric and Earth System research/physics University of Helsinki Joint International research Laboratory of Atmospheric and Earth System Sciences Nanjing University Department of Environmental Science & Bolin centre for Climate research Stockholm University Department of Chemistry and Molecular Biology University of Gothenburg Institute for Ion and Applied physics University of Innsbruck Ionicon Analytik GmbH Laboratory for Atmospheric physics Institute for Physics Research Universidad Mayor de San Andrés Institute of physics University of Sao Paulo Institute for Geosciences and Environmental research (IGE) University of Grenoble Alpes Agrarian Sciences Institute Federal University of Uberl?ndia Beijing Advanced Innovation Center for Soft Matter Science and Engineering Beijing University of Chemical Technology Department of Atmospheric and Oceanic Sciences University of Maryland Aerodyne research Inc. Department of Environmental System Science ETH Zürich Switzerland and Laboratory of Atmospheric Chemistry Paul Scherrer Institute

New particle formation(NPF) in the tropical free troposphere(FT) is a globally important source of cloud condensation nuclei, affecting cloud properties and climate. Oxidized organic molecules(OOMs)produced from biogenic volatile organic compounds are believed to contribute to aerosol formation in the tropical FT, but without direct chemical observations. We performed in situ molecular-level OOMs measurements at the Bolivian station Chacaltaya at 5240 m above sea level, on the western edge of Amazonia. For the first time, we demonstrate the presence of OOMs, mainly with 4–5 carbon atoms, in both gas-phase and particle-phase(in terms of mass contribution) measurements in tropical FT air from Amazonia. These observations, combined with air mass history analyses, indicate that the observed OOMs are linked to isoprene emitted from the rainforests hundreds of kilometers away. Based on particle-phase measurements, we find that these compounds can contribute to NPF, at least the growth of newly formed nanoparticles, in the tropical FT on a continental scale. Thus, our study is a fundamental and significant step in understanding the aerosol formation process in the tropical FT.

关键词： oxidized organic molecules tropical aerosol formation Amazon free troposphere

Expanded Porphyrin Exhibiting Off-Centered Out-of-Plane Coordination to Dysprosium

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CCS Chemistry 2024年第7期6卷 1731-1738页

作者： Dmitry I.Nazarov Jorge Labella Alexey V.Kuzmin Maxim A.Faraonov Evgenii N.Ivanov Salavat S.Khasanov Tomas Torres Mikhail K.Islyaikin Dmitri V.Konarev federal research Center of Problems of chemical physics and Medicinal Chemistry RAS 142432 Chernogolovka Department of Organic Chemistry Universidad Autonoma de Madrid28049 Madrid Institute of Solid-State physics RAS 142432 Chernogolovka research Institute of Macroheterocycles Ivanovo State University of Chemistry and Technology15300 Ivanovo G.A.Krestov Institute of Solution Chemistry of the Russian Academy of Sciences 153045 Ivanovo Institute for Advanced research in chemical Sciences Universidad Autonoma de Madrid28049 Madrid IMDEA-Nanociencia 28049 Madrid

The complexation of high-spin lanthanides to porphyrinoids is a powerful strategy for the development of advanced molecular *** this context,the use of expanded porphyrinoids remains elusive since their coordination chemistry is challenging to ***,taking inspiration from on-surface chemistry,we explored the coordination of Dy^(3+)to a six-membered porphyrinoid,namely,the hemihexaphyrazine ***,we observed the selective formation of a mono-nuclear off-centered,out-of-plane H_(2)Hhp-Dy^(3+)complex when performing the complexation under reductive *** this reaction,the oxidation state of the macrocycle did not *** X-ray diffraction analysis,we found that the coordination number of Dy in this complex was *** macrocycle cocrystallized with decamethylcobaltocene(Cp_(2)^(*)Co)molecules,giving rise to a wellordered solid-state packing,governed byπ-π*** a result of this organization,a small magnetic coupling between the neighboring molecules was *** in all,this work provides key insights into the coordination of magnetically active metals with expanded porphyrinoids,thus motivating the development of advanced spintronic devices.

关键词： porphyrins dysprosium macrocycle coordination chemistry magnetism

The initial stages of Li_(2)O_(2) formation during oxygen reduction reaction in Li-O_(2) batteries:The significance of Li_(2)O_(2) in charge-transfer reactions within devices

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Journal of Energy Chemistry 2024年第1期88卷 223-231,I0006页

作者： Daniela M.Josepetti Bianca P.Sousa Simone A.J.Rodrigues Renato G.Freitas Gustavo Doubek Advanced Energy Storage Division LABCenter for Innovation on New EnergiesSchool of Chemical EngineeringUniversity of CampinasAv Albert Einstein 50013083-852CampinasSPBrazil Institute of physics&Department of Chemistry Laboratory of Computational MaterialsFederal University of Mato Grosso78060-900CuiabáMTBrazil

Lithium-oxygen batteries are a promising technology because they can greatly surpass the energy density of lithium-ion ***,this theoretical characteristic has not yet been converted into a real device with high *** with air contamination,metallic lithium reactivity,and complex discharge and charge reactions are the main issues for this technology.A fast and reversible oxygen reduction reaction(ORR)is crucial for good performance of secondary batteries',but the partial knowledge of its mechanisms,especially when devices are concerned,hinders further *** this perspective,the present work uses operando Raman experiments and electrochemical impedance spectroscopy(EIS)to assess the first stages of the discharge processes in porous carbon electrodes,following their changes cycle by cycle at initial operation.A growth kinetic formation of the discharge product signal(Li_(2)O_(2))was observed with operando Raman,indicating a first-order reaction and enabling an analysis by a microkinetic *** solution mechanism in the evaluated system was ascribed for an equivalent circuit with three time *** the time constant for the anode interface reveals to remain relatively constant after the first discharge,its surface seemed to be more *** model indicated that the reaction occurs at the Li_(2)O_(2) surface,decreasing the associated resistance during the initial discharge ***,the growth of Li_(2)O_(2) forms a hetero-phase between Li_(2)O_(2)/electrolyte,while creating a more compact and homogeneous on the Li_(2)O_(2)/cathode *** methodology here described thus offers a way of directly probing changes in surface chemistry evolution during cycling from a device through EIS analysis.

关键词： Li-O_(2)battery Operando Raman analysis Equivalent circuit modeling Time-constant distribution

Elucidating elusive quaternary selenide EuCeCuSe3:Synthesis,crystal structure,properties and theoretical studies

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Journal of Rare Earths 2024年第1期42卷 163-171,I0006页

作者： Maxim V.Grigoriev Anna V.Ruseikina Maxim S.Molokeev Vladimir A.Chernyshev Aleksandr S.Aleksandrovsky Alexander S.Krylov Svetlana N.Krylova Nikolai P.Shestakov Dmitriy A.Velikanov Alexander A.Garmonov Alexey V.Matigorov Evgeny A.Ostapchuk Thomas Schleid Damir A.Safin Laboratory of Theory and Optimization of chemical and Technological Processes University of TyumenVolodarskogo Str.6625003TyumenRussian Federation Kirensky Institute of physics Federal Research Center KSC SB RASAkademgorodok 50 Bld.38660036KrasnoyarskRussian Federation Department of physics Far Eastern State Transport UniversitySerysheva Str.47680021KrasnoyarskRussian Federation Institute of Natural Sciences and Mathematics Ural Federal University Named After the First President of Russia B.N.YeltsinMira Str.19620002EkaterinburgRussian Federation Department of Photonics and Laser Technology Siberian Federal UniversitySvobodnii Ave.79660079KrasnoyarskRussian Federation Institute of physics and Technology University of TyumenVolodarskogo Str.6625003 TyumenRussian Federation Institute for Inorganic Chemistry University of StuttgartPfaffenwaldring 55D-70569StuttgartGermany Scientific and Educational and Innovation Center for chemical and Pharmaceutical Technologies Ural Federal University named after the First President of Russia B.N.YeltsinMira Str.19620002 EkaterinburgRussian Federation University of Tyumen Volodarskogo Str.6625003TyumenRussian Federation

We report on the novel heterometallic quaternary selenide EuCeCuSe3,the fabrication of which has been a challenge until this *** structure of the reported selenide was elucidated from the powder X-ray diffraction data,which revealed the formation of EuCeCuSe3with excellent yield(96.7%)accompanied with a minor fraction of CeSe2(3.3%),and was best solved in orthorhombic space group Pnma with the BaLaCuS3structural ***,the crystal structure of the title compound completes the row of the heterometallic quaternary selenides EuRECuSe3(RE=La,Pr,Nd,Sm,Eu,Gd,Tb,Dy,Ho,Er,Tm,Yb,Lu,Y),of which the cerium-based derivative exclusively belongs to the BaLaCuS3structural *** distortion of the CuSe4polyhedron was compared for the whole series of EuRECuSe3compounds using theτ4-descriptor for four coordinated ions,which revealed the highest degree of distortion for the Ce3+-containing selenide,followed by the La3+-based ***,the crystallographic and geometrical parameters of the reported selenide were discussed in comparison to the Ce3+-based sulfides SrCeCuS3and *** initio calculations of the crystal structure,a phonon spectrum and elastic constants for the crystal of EuCeCuSe3were also *** types and wavenumbers of fundame ntal modes were determined and the involvement of ions participating in the phonon modes was *** experimental IR spectrum of the reported selenide was interpreted and found to be in agreement with the calculated *** experimental direct band gap of EuCeCuSe3was measured to be 1.36 eV that is consistent with the concept of its origin due to interband transitions between orbitals emerging mainly from 4f(valence band)and 5d(conduction band)levels of the Eu2+*** dependence of the Young’s modulus on the direction demonstrates the anisotropy of the elastic properties,while the Vickers hardness for EuCeCuSe3was calculated to be 5.2 ***,the title compound is paramagnetic above 4 K.

关键词： Quaternary selenide Synthesis Crystal structure Ab initio calculations Magnetic measurements Spectroscopy

Construction of Dynamic Alloy Interfaces for Uniform Li Deposition in Li-Metal Batteries

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Energy & Environmental Materials 2024年第3期7卷 64-71页

作者： Qingwen Li Yulu Liu Ziheng Zhang Jinjie Chen Zelong Yang Qibo Deng Alexander V.Mumyatov Pavel A.Troshin Guang He Ning Hu Tianjin Key Laboratory of Advanced Functional Porous Materials Institute for New Energy Materials and Low-Carbon TechnologiesSchool of Materials Science and EngineeringTianjin University of TechnologyTianjin 300384China Tianneng Co.Ltd Huzhou 313100China Key Laboratory of Hebei Province on Scale-span Intelligent Equipment Technology Tianjin Key Laboratory of Power Transmission and Safety Technology for New Energy Vehiclesand School of Mechanical EngineeringHebei University of TechnologyTianjin 300401China federal research Center for Problems of chemical physics and Medicinal Chemistry Academician Semenov ave.1Chernogolovka Moscow Region 142432Russia Zhengzhou research Institute of HIT 26 Longyuan East 7thJinshui DistrictZhengzhou 450000Henan Province China Harbin Institute of Technology 92 West Dazhi StreetNan Gang DistrictHarbin 150001China

It is well accepted that a lithiophilic interface can effectively regulate Li deposition behaviors,but the influence of the lithiophilic interface is gradually diminished upon continuous Li deposition that completely isolates Li from the lithiophilic ***,we perform in-depth studies on the creation of dynamic alloy interfaces upon Li deposition,arising from the exceptionally high diffusion coefficient of Hg in the amalgam solid *** a comparison,other metals such as Au,Ag,and Zn have typical diffusion coefficients of 10-20 orders of magnitude lower than that of Hg in the similar solid solution *** difference induces compact Li deposition pattern with an amalgam substrate even with a high areal capacity of 55 mAh cm^(-2).This finding provides new insight into the rational design of Li anode substrate for the stable cycling of Li metal batteries.

关键词： diffusion coefficient dynamic alloy interfaces Li dendrites Li solid solution uniform Li deposition

Structural correlation and chemistry of molten NaF-ScF_(3) with dissolved metal aluminium:TG/DTA,XRD,NMR and molecular dynamics simulations

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Rare Metals 2024年第7期43卷 3356-3369页

作者： Aydar Rakhmatullin Frantisek Simko Didier Zanghi Zuzana Netriová Ilya BPolovov Ayrat Dimiev Konstantin V.Maksimtsev Catherine Bessada Michal Korenko Conditions Extrêmes et Materiaux:Haute Température et Irradiation CEMHTIUPR 3079-CNRS Univ Orleans45071 OrleansFrance Department of Molten Systems Institute of Inorganic ChemistrySlovak Academy of Sciences84536 BratislavaSlovakia centre of Excellence for Advanced Materials Application-CEMEA Slovak Academy of Sciences84511Bratislava.Slovakia Department of Rare Metals and Nanomaterials Institute of Physics and TechnologyUral Federal UniversityUral Federal University620002 EkaterinburgRussia Alexander Butlerov Institute of Chemistry Kazan Federal University420008KazanRussia

For the first time,the mechanism of metal aluminum dissolution in NaF-ScF_(3) eutectic melts and the chemical interaction between the constituents of this mixture have been thoroughly studied by a combination of differential thermal analysis(DTA),high temperature and solid-state nuclear magnetic resonance(NMR),and X-ray diffraction(XRD) coupled with the molecular dynamic *** formation of an insoluble Al_(3)Sc alloy in molten(NaF-ScF_(3))_(eut)system was proven,and the chemical mechanism of this aluminothermic Al_(3)Sc alloy production was *** ex situ examinations bring to light the formation of NaScF_4 and solid solution of Na_(3)(Al,Sc)F_(6) in cooled *** molecular dynamics calculations of the bath allow us to construct the structural model and to predict viscosity,density and electrical conductivity of the reagent melt to help to optimize the conditions of the alloy synthesis.

关键词： Scandium Alloy Molten salts NMR Molecular dynamics

Kinetics of oxidative coupling of methane:Bridging the gap between comprehension and description

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Journal of Natural Gas Chemistry 2009年第3期18卷 273-287页

作者： Mikhail Sinev Zukhra Fattakhova Vladimir Lomonosov Yurii Gordienko semenov Institute of chemical physics ZAO "SCHAG" Company

The development of notions about the mechanism of the oxidative coupling of methane （OCM） over oxide catalysts and corresponding progress in its kinetic description are reviewed and discussed. The latter becomes essential at the stage of scaling up and optimization of the process in pilot and industrial reactors. It is demonstrated that the main achievements in the development of kinetic models can be reached by combining the approaches conventionally used in homogeneous gas-phase kinetics and in heterogeneous catalysis. In particular, some important features of the OCM process can be described if several elementary reactions of free radical species （formation and transformation） with surface active sites are included into the detailed scheme of methane oxidation in gas. However, some important features, such as a non-additive character of the reciprocal influence of methane and ethane in the case of their simultaneous presence in the reaction mixture, cannot yet be described and comprehended in the framework of schemes developed so far. Possible ways towards an advanced kinetic model, accounting the main principles of catalyst functioning （redox nature of active sites） and pathways of product formation （via free radicals） are traced.

关键词： natural gas methane oxidative coupling of methane ethane ethylene kinetics mechanism rate equations