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

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

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Flat-footed Females and Missing Males:A New Genus and Species of Pleciofungivoridae(Diptera:Bibionomorpha)Represents the First Record of the Family from Mid-Cretaceous Kachin Amber

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Acta Geologica Sinica(English Edition) 2024年第3期98卷 541-547页

作者： ZHANG Qingqing Wiesław KRZEMINSKI Jan SevCIK Vladimir BLAGODEROV Agnieszka SOSZYNSKA Kornelia SKIBINSKA Yunnan Key Laboratory for Palaeobiology Institute of PalaeontologyYunnan UniversityKunming 650500China MEC International Joint Laboratory for Palaeobiology and Palaeoenvironment Yunnan UniversityKunming 650500China State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology and Center for Excellence in Life and PaleoenvironmentChinese Academy of SciencesNanjing 210008China Institute of Systematics and evolution of Animals Polish Academy of Sciences52551 KrakówPoland University of Ostrava Faculty of ScienceDepartment of Biology and EcologyChittussiho 10CZ-71000 OstravaCzech Republic National Museums Scotland EdinburghUK Natural History Museum LondonUK University of Lodz Faculty of Biology and Environmental ProtectionDepartment of Invertebrate Zoology and HydrobiologyBanacha 12/1690-237ŁódźPoland

A new genus and species,Cretopleciofungivora simpsoni *** ***.,from the extinct family Pleciofungivoridae(Diptera:Bibionomorpha),is discovered in mid-Cretaceous Kachin ***,this family was known only from imprints in sedimentary rocks of the Jurassic and the Lower *** of a representative of Pleciofungivoridae in Kachin amber confirms the presence of the family in the Upper *** new species has a unique structure of fore tarsus,with lobed and extended tarsal segments Ⅱ to Ⅳ,a feature hitherto known only in a few species of extant *** not particularly rare,the new species is currently known only from female *** reasons for this phenomenon,very unusual in Sciaroidea,are briefly discussed,including parthenogenesis as a potentially plausible hypothesis.

关键词： fungus gnats Sciaroidea Upper Cretaceous Burmese amber swollen tarsomeres

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Visible-light-induced synthesis of phosphorylated N-heterocycles through proton-coupled electron transfer

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Science China Chemistry 2021年第5期64卷 681-683页

作者： Vera A.Vil’ Igor B.Krylov alexander O.Terent’ev N.D.Zelinsky Institute of Organic Chemistry of the Russian Academy of Sciences Moscow 119991Russia

Phosphorus-containing organic compounds are important feedstock for the synthesis of value-added bioactive ***,the development of highly efficient synthetic methods for the construction of phosphorus-element bonds has drawn huge attention in the past decades[1].Particularly,the formation of P–C bonds from phosphoruscentered radicals has been demonstrated to be one of the most efficient and convenient strategies,which has been widely applied for the synthesis of organic phosphorus compounds in recent years.

关键词： synthesis bonds phosphorus

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Mixed hetero-/homogeneous TiO_(2)/N-hydroxyimide photocatalysis in visible-light-induced controllable benzylic oxidation by molecular oxygen

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Chinese Journal of Catalysis 2021年第10期42卷 1700-1711页

作者： Igor B.Krylov Elena R.Lopat'eva Irina R.Subbotina Gennady I.Nikishin Bing Yu alexander O.Terent'ev N.D.zelinsky institute of organic chemistry of the russian academy of sciences moscow 119991russian federation Mendeleev university of chemical technology of russia moscow 125047russian federation Green catalysis center college of chemistryzhengzhou universityzhengzhou 450001henanchina

Homogeneous and heterogeneous types of catalysis are frequently considered as separate disciplines or even opposed to each *** the present work,a new type of mixed het-ero-/homogeneous catalysis was demonstrated for the case of selective alkylarene oxidation by molecular *** proposed catalytic system consists of two widely available components:N-hydroxyphthalimide(NHPI,a homogeneous organocatalyst for free-radical chain reactions)and nanosized TiO_(2)(heterogeneous UV-active photoredox catalyst).The interaction of NHPI with TiO_(2) allows for a shift from UV to visible light photoredox activity and generation of phthalimide-N-oxyl(PINO)radicals that diffuse into the solution where NHPI/PINO-catalyzed free-radical chain reaction can proceed without the additional light input providing a fundamental increase in energy *** NHPI/TiO_(2) ratio controls the selectivity of oxidation affording preferential formation of hydroperoxide or ketone from alkylarene.

关键词： TiO_(2) Photoredox catalysis N-hydroxyphthalimide N-oxyl radicals Aerobic oxidation

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激光辐射波长和脉冲寿命对碲化镉熔化阈值的影响

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材料导报 2024年第7期38卷 40-45页

作者：列维茨基·谢尔盖曹泽祥柯巴·亚历山大柯巴·玛丽亚乌克兰国家科学院半导体物理研究所基辅03028 乌克兰国立技术大学物理技术学院基辅03058 乌克兰国民警卫研究所国家安全系基辅03028

碲化镉的相对分子量为240,密度为5.885 g/cm^(3),熔点为1092℃。碲化镉是一种Ⅱ-Ⅵ族的化合物半导体材料,属于直接带隙型,带隙宽度为1.56 ev。碲化镉是制造X射线、伽马射线和红外线探测器的基本材料。对碲化镉的特别关注主要是由于其大... 详细信息

碲化镉的相对分子量为240,密度为5.885 g/cm^(3),熔点为1092℃。碲化镉是一种Ⅱ-Ⅵ族的化合物半导体材料,属于直接带隙型,带隙宽度为1.56 ev。碲化镉是制造X射线、伽马射线和红外线探测器的基本材料。对碲化镉的特别关注主要是由于其大原子数和大的光电吸收截面。在基于CdTe的伽马辐射势垒探测器结构中,其表面的处理方法之一是纳秒激光照射,在某些情况下,纳秒激光照射可以在触点(Ag、In、Au)和势垒形成的技术处理阶段优化所需的表面参数。另一种方法是在脉冲激光照射下在碲化镉表面形成有序的纳米结构。对基于半导体及其结构的脉冲激光器,可根据其不同的脉冲持续时间τ_(p)和辐射波长λ将其分类。例如,红宝石激光器(λ=694 nm)、钕激光器(一次谐波1064 nm和两次谐波532 nm)、准分子KrF激光器(248 nm)和XeF激光器(351 nm)等,其脉冲持续时间分别为7、20、80、120 ns。这些激光器常被应用于表面修饰等领域。因此,往往有必要事先知道或至少估计在脉冲激光辐射下碲化镉表面的熔化温度和阈值,这取决于激光脉冲持续时间τ_(p)、辐射波长(光吸收系数α(λ))以及碲化镉表面本身的电物理参数,特别是表面重组率S和非平衡电荷载流子的寿命。这些参数取决于表面处理的方法和掺杂物的浓度。在上述情况下,实验研究是非常耗费人力和时间的,因此基于τ_(p)、α(λ)和碲化镉表面本身的电物理参数对融化阈值th和表面温度进行理论计算变得非常重要。本工作采用激光照射碲化镉,辐射波长为300~800 nm,脉冲持续时间为7~120 ns。为了以非破坏性的和有效的方法来管理接近表面层状态的CdTe,在T=80 K下进行了光致发光实验。为了监测熔化阈值,研究了由Acrorad公司制造和抛光的尺寸为5 mm×5 mm×0.5 mm的Cl补偿p-CdTe(111)单晶的光致发光光谱。经过研究发现,在激光脉冲寿命从7ns到1μs的范围内,CdTe熔化阈值明显取决于光吸收系数α(λ)。因为在脉冲寿命长于1μs的情况下,热扩散深度明显大于CdTe中的激光辐射穿透深度,并开始依赖于反射系数R(λ)。对于较短的激光脉冲长度τ_(p),当辐射波长λ变化时,熔化阈值会发生显著变化。同时,非平衡过剩载流子参数的变化(如表面重组速度S从10^(3)m/s增加到10^(5)m/s,还有扩散深度LD从0.4μm增加到2μm)会对CdTe熔化阈值产生至少25%的影响。而且红宝石激光的脉冲持续时间在(20±5)ns区间内的变化导致相对熔化阈值的变化(ΔIth/Ith)为35%。CdTe熔化阈值的计算值可以有效地被用于优化脉冲激光对晶体的表面处理与掺杂。

关键词：碲化镉熔化阈值脉冲激光辐照半导体激光掺杂

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Modeling and optimization of 200mm and 300mm Cz Si growth processes

Modeling and optimization of 200mm and 300mm Cz Si growth pr...

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第十七届全国晶体生长与材料学术会议(CCCG-17)

作者： Andrei Vorob’ev alexander Sidko alexander Kuliev Andrey Smirnov Vladimir Kalaev STR Group Inc.

Around 25%of silicon wafers for photovoltaics and most of silicon wafers for microelectronics are manufactured using Cz growth *** all major applications,there are requirements to improve crystal quality and reduce pr...

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N-羟基邻苯二甲酰亚胺酯在光催化烷基化反应中的研究进展

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有机化学 2021年第12期41卷 4661-4689页

作者：贺帅旗李昊聪陈晓岚 Igor B.Krylov alexander O.Terent'ev 屈凌波於兵郑州大学化学学院绿色催化中心郑州450001 俄罗斯科学院泽林斯基有机化学研究所俄罗斯莫斯科119991

N-羟基邻苯二甲酰亚胺(NHP)酯可以由对应的羧酸衍生而来,是一类价廉、易得、稳定、具有高光活性的化合物.近年来,NHP酯类化合物在光催化脱羧反应中受到了广泛关注.根据光催化剂的类型,综述了可见光促进下NHP酯参与的烷基化反应的研究进展.

关键词：邻苯二甲酰亚胺酯光催化脱羧烷基化光催化剂

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Effect of electron injection in copper-contacted graphene nanoribbons

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Nano Research 2016年第9期9卷 2735-2746页

作者： Konstantin A.Simonov Nikolay A.Vinogradov alexander S.Vinogradov alexander V.Generalov Gleb I.Svirskiy Attilio A.Cafolla Nils Martensson Alexei B. Preobrajenski Department of Physics and Astronomy Uppsala UniversityUppsala Box 51675120Sweden MAX Ⅳ Laboratory Lund UniversityLund Box 11822100Sweden V.A.Fock Institute of Physics St.Petersburg State UniversitySt.Petersburg 198504Russia School of Physical Sciences Dublin City UniversityDublin 9Ireland

For practical electronic device applications of graphene nanoribbons (GNRs), it is essential to have abrupt and well-defined contacts between the ribbon and the adjacent metal lead. By analogy with graphene, these contacts can induce electron or hole doping, which may significantly affect the I/V characteristics of the device. Cu is among the most popular metals of choice for contact materials. In this study, we investigate the effect of in situ intercalation of Cu on the electronic structure of atomically precise, spatially aligned armchair GNRs of width N = 7 (7-AGNRs) fabricated via a bottom-up method on the Au(788) surface. Scanning tunneling microscopy data reveal that the complete intercalation of about one monolayer of Cu under 7-AGNRs can be facilitated by gentle annealing of the sample at 80 °C. Angle-resolved photoemission spectroscopy (ARPES) data clearly reflect the one-dimensional character of the 7-AGNR band dispersion before and after intercalation. Moreover, ARPES and core-level photoemission results show that intercalation of Cu leads to significant electron injection into the nanoribbons, which causes a pronounced downshift of the valence and conduction bands of the GNR with respect to the Fermi energy (ΔE ~ 0.5 ev). As demonstrated by ARPES and X-ray absorption spectroscopy measurements, the effect of Cu intercalation is restricted to n-doping only, without considerable modification of the band structure of the GNRs. Post-annealing of the 7-AGNRs/Cu/Au(788) system at 200 °C activates the diffusion of Cu into Au and the formation of a Cu-rich surface Au layer. Alloying of intercalated Cu leads to the recovery of the initial position of GNR-related bands with respect to the Fermi energy (E F), thus, proving the tunability of the induced n-doping.

关键词： graphene nanoribbons bottom-up method copper intercalation charge injection angle-resolved photoemission spectroscopy (ARPES) scanning tunneling microscopy

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Helium droplet assisted synthesis of plasmonic Ag@ZnO core@shell nanoparticles

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Nano Research 2020年第11期13卷 2979-2986页

作者： alexander Schiffmann Thomas Jauk Daniel Knez Harald Fitzek Ferdinand Hofer Florian Lackner Wolfgang E.Ernst Institute of Experimental Physics Graz University of TechnologyA-8010GrazAustria Institute of Electron Microscopy and Nanoanalysis&Graz Centre for Electron Microscopy Graz University of TechnologyA-8010GrazAustria

Plasmonic Ag@ZnO core@shell nanoparticles are formed by synthesis inside helium droplets with subsequent deposition and controlled *** particle size and shape can be controlled from spherical sub-10 nm particles to larger elongated *** advantage of the method is the complete absence of solvents,precursors,and other chemical *** obtained particle morphology and elemental composition have been analyzed by scanning transmission electron microscopy(STEM)and energy dispersive X-ray spectroscopy(EDS).The results reveal that the produced particles form a closed and homogeneous ZnO layer around a 2–3 nm Ag core with a uniform thickness of(1.33±0.15)nm and(1.63±0.31)nm for spherical and wire-like particles,*** results are supported by ultraviolet photoelectron spectroscopy(UPS),which indicates a fully oxidized shell layer for the particles studied by *** plasmonic properties of the produced spherical Ag@ZnO core@shell particles are investigated by two-photon photoelectron(2PPE)*** excitation of the localized surface plasmon resonance in Ag at around 3 ev,plasmonic enhancement leads to the liberation of electrons with high kinetic *** is observed for both Ag and Ag@ZnO particles,showing that even if a Ag cluster is covered by the ZnO layer,a plasmonic enhancement can be observed by photoelectron spectroscopy.

关键词： nanoparticle helium droplet plasmonics photoelectrons

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Electronic properties of wurtzite GaAs： A correlated structural, optical, and theoretical analysis of the same polytypic GaAs nanowire

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Nano Research 2018年第9期11卷 4708-4721页

作者： alexander Senichev Pierre Corfdir Oliver Brandt Manfred Ramsteiner Steffen Breuer Jorg Schilling Lutz Geelhaar Peter Werner Max-Planck-lnstitut fur Mikrostrukturl)hysik Halle 06120 Germany PauI-Drude-lnstitut for Festkorperelektronik Berlin 10117 Germany Centre for Innovation Competence SiLi-nano Martin-Luther-Universitat Halle 06120 Germany Present address: Birck Nanotechnology Center Purdue University West Lafayette Indiana 47907 USA Present address: Fraunhofer HHI Berlin 10587 Germany Present address: ABB Corporate Research Baden-Dattwi15405 Switzerland

III-V compound semiconductor nanowires are generally characterized by the coexistence of zincblende and wurtzite structures. So far, this polytypism has impeded the determination of the electronic properties of the metastable wurtzite phase of GaAs, which thus remain highly controversial. In an effort to obtain new insights into this topic, we cross-correlate nanoscale spectral imaging by near-field scanning optical microscopy with a transmission electron microscopy analysis of the very same polytypic GaAs nanowire dispersed onto a Si wafer. Thus, spatially resolved photoluminescence spectra could be unambiguously assigned to nanowire segments whose structure is known with lattice-resolved accuracy. An emission energy of 1.528 ev was observed from extended zincblende segments, revealing that the dispersed nanowire was under uniaxial strain presumably due to interaction with its supporting substrate. These crucial information and the emission energy obtained for extended pure wurtzite segments were used to perform envelope function calculations of zincblende quantum disks in a wurtzite matrix as well as the inverse structure. In these calculations, we varied the fundamental bandgap, the electron mass, and the band offset between zincblende and wurtzite GaAs. From this multi-parameter comparison with the experimental data, we deduced that the bandgap between the F8 conduction and A valence band ranges from 1.532 to 1.539 ev in strain-free wurtzite GaAs, and estimated values of 1.507 to 1.514 ev for the F7-A bandgap.

关键词： nanowires crystal-phase quantumstructures wurtzite GaAs strain near-field scanning optical microscopy photoluminescence

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