Nakajima, Atsushi

写真a

Affiliation

Faculty of Science and Technology, Department of Chemistry （Yagami）

Position

Professor

External Links
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Career 【 Display / hide 】

  • 1989.04
    -
    1994.03

    大学助手(理工学部化学科)

  • 1994.04
    -
    1997.03

    大学専任講師(理工学部化学科)

  • 1997.04
    -
    2001.03

    大学助教授(理工学部化学科)

  • 2001.04
    -
    Present

    大学教授(理工学部化学科)

  • 2001.04
    -
    Present

    大学院理工学研究科委員

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Academic Background 【 Display / hide 】

  • 1984.03

    The University of Tokyo, Faculty of Science, 化学科

    University, Graduated

  • 1986.03

    The University of Tokyo, Graduate School, Division of Natural Science, 化学専攻

    Graduate School, Completed, Master's course

  • 1989.03

    The University of Tokyo, Graduate School, Division of Natural Science

    Graduate School, Completed, Doctoral course

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Academic Degrees 【 Display / hide 】

  • Dr. Sc., The University of Tokyo, Coursework, 1989.03

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Matters concerning Career Achievements 【 Display / hide 】

  • 2001.10
    -
    2007.09

    大学学生総合センター委員(矢上支部)

  • 2006.04
    -
    2008.03

    大学院理工学研究科専修主任(機能デザイン科学)

  • 2008.04
    -
    2009.09

    大学理工学部企画室会議委員

  • 2009.04
    -
    2011.03

    大学理工学部学習指導副主任(化学科)

  • 2010.04
    -
    2013.09

    大学理工学部企画室会議委員

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Research Areas 【 Display / hide 】

  • Nanotechnology/Materials / Fundamental physical chemistry (Physical Chemistry)

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Research Themes 【 Display / hide 】

  • Nanocluster Assembled Material Science, 

    2009
    -
    2015

  • 科学技術振興機構　戦略創造プログラム(CREST) 研究課題「次世代光磁気材料を指向したナノデザイン制御」, 

    2002
    -
    2007

    　View Summary

    本研究では、多元的な化学組成の制御を通じて電子構造をデザインした複合ナノクラスターを創成し、このクラスターを機能単位とする二次元系ナノクラスター物質を、ナノメートルオーダーで周期的にデザイン制御した固体表面上への選択的なソフトランディングによって構築します。ナノデザイン制御されたクラスター物質での電

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Books 【 Display / hide 】

  • Electronic properties of transition metal-benzene sandwich clusters

    Masubuchi T., Nakajima A., Theoretical Chemistry for Advanced Nanomaterials: Functional Analysis by Computation and Experiment, 2020.01

    　View Summary

    Organometallic clusters composed of transition metal atoms and benzene molecules have been topics of great interest from both fundamental and technological points of view. In this chapter, we review the progress in the physical chemistry of transition metal-benzene clusters. The intrinsic properties of transition metal-benzene clusters as a function of cluster size are investigated by gasphase experiments, often in combination with quantum chemical calculations. In particular, vanadium-benzene clusters denoted VnBzm, showing magic numbers at m = n + 1, n, and n – 1, are characterized to possess multiple-decker sandwich structures, where vanadium atoms and benzene molecules are alternately piled up. Moreover, the discovery of such multiple-decker formation is a cornerstone in bottom-up approaches of molecular magnetism. The interplay of mass spectrometry, laser spectroscopies, and density functional calculations reveals that multiple-decker VnBzm clusters exhibit monotonic increase in magnetic moment with the number of layers. Anion photoelectron spectroscopic studies allow direct observations of the geometric and electronic structures of sandwich clusters and their anions. Major progress in this direction includes the recent characterization of tilted multipledecker sandwich cluster anions composed of manganese atoms and benzene molecules. The sandwich clusters with high-spin characteristics will hopefully be exploited as building blocks in advanced electronic and magnetic nanomaterials via controlled assembly.

  • Formation of superatom monolayer using nanocluster ion source based on high-power impulse magnetron sputtering

    Nakajima A., Encyclopedia of Interfacial Chemistry: Surface Science and Electrochemistry, 2018.01

    　View Summary

    The assembled monolayer of superatomic nanocluster ions synthesized in the gas phase is formed with monodispersive immobilization of Ta atom-encapsulated Si16 cage superatom (Ta@Si16) with an intensive ion source based on high-power impulse magnetron sputtering (HiPIMS). Scanning tunneling microscopy and spectroscopy have demonstrated that superatom cations of Ta@Si16+ can be densely immobilized on C60-terminated surfaces while retaining their cage shape by forming charge transfer (CT) complexes ((Ta@Si16)+C60-) on the surfaces. Its chemical states of Ta@Si16 deposited on an electron acceptable C60 fullerene film were evaluated by X-ray photoelectron spectroscopies (XPS). XPS results for Si, Ta, and C elements showed that Ta@Si16 combines with a single C60 molecule to form (Ta@Si16)+C60-. The high thermal and chemical robustness of the superatomic CT complex has been revealed by the XPS measurements conducted before and after heat treatment and oxygen exposure. The formation of robust superatom monolayer with HiPIMS demonstrates that the superatoms including metal-encapsulating silicon cage superatoms have a promising potential to be utilized for building blocks of novel functional nanomaterials.

  • 最新 実用真空技術総覧　クラスタービーム生成

    NAKAJIMA ATSUSHI, ㈱産業技術サービスセンター, 2017

  • シリコンフラーレン

    NAKAJIMA ATSUSHI, 慶應義塾機関紙　三田評論, 2014

  • 現代界面コロイド科学の事典　10.4節「金属ナノクラスター」

    NAKAJIMA ATSUSHI, 丸善, 2010

    Scope: 240-241

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Papers 【 Display / hide 】

  • Extended X-ray Absorption Fine Structure (EXAFS) Measurements on Alkali Metal Superatoms of Ta-Atom-Encapsulated Si<inf>16</inf> Cage

    Inoue T., Ina T., Masai H., Kondo N., Matsui F., Kinoshita T., Nakajima A.

    Journal of Physical Chemistry Letters （American Chemical Society)     5376 - 5381 2024.06

    Research paper (scientific journal), Joint Work, Last author, Corresponding author, Accepted

    　View Summary

    The silicon cage nanoclusters encapsulating a tantalum atom, termed Ta@Si16, exhibit characteristics of alkali metal “superatoms (SAs)”. Despite this conceptual framework, the precise structures of Ta@Si16 and Ta@Si16+ remain unclear in quantum calculations due to three energetically close structural isomers: C3v, Td, and D4d structures. To identify the geometrical structure of Ta@Si16 SAs, structural analysis was conducted using extended X-ray absorption fine structure (EXAFS) with a high-intensity monochromatic X-ray source, keeping anaerobic conditions. Focusing on “superordered” films, which constitute amorphous thin films composed solely of Ta@Si16 SAs, this analysis preserved locally ordered structures. Spectral comparisons between experimental and simulated Ta L3-edge EXAFS unveil that Ta@Si16 SAs on a substrate adopt a C3v-derived structure, while Si K-edge EXAFS introduces spectral ambiguity in structural identifications, attributed to both intracluster and intercluster scatterings. These findings underscore the significance of locally ordered structure analyses in understanding and characterizing novel nanoscale materials.

  • Alkaline Earth Metal Superatom of W@Si<inf>16</inf>: Characterization of Group 6 Metal Encapsulating Si<inf>16</inf> Cage on Organic Substrates

    Terasaka K., Kamoshida T., Ichikawa T., Yokoyama T., Shibuta M., Hatanaka M., Nakajima A.

    Journal of the American Chemical Society （American Chemical Society)  146 （ 14 ） 9605 - 9613 2024.04

    Research paper (scientific journal), Joint Work, Accepted,  ISSN  00027863

    　View Summary

    Transition metal atom (M)-encapsulating silicon cage nanoclusters (M@Si16) exhibit a superatomic nature, depending on the central M atom owing to the number of valence electrons and charge state on organic substrates. Since M@Si16 superatom featuring group 4 and 5 transition metal atoms exhibit rare-gas-like and alkali-like characteristics, respectively, group 6 transition metal atoms are expected to show alkaline earth-like behavior. In this study, M@Si16, comprising a central atom from group 6 (MVI = Cr, Mo, and W) were deposited on C60 substrates, and their electronic and chemical stabilities were investigated in terms of their charge state and chemical reactivity against oxygen exposures. In comparison to alkali-like Ta@Si16, the extent of charge transfer to the C60 substrate is approximately doubled, while the oxidative reactivity is subdued for MVI@Si16 on C60, especially for W@Si16. The results show that a divalent state of MVI@Si162+ appears on the C60 substrate, which is consistently calculated to be a symmetrical cage structure of W@Si162+ in C3v, revealing insights into the “periodic law” of M@Si16 superatoms pertaining to the characteristics of alkaline earth metals.

  • Oxidative Activation of Small Aluminum Nanoclusters with Boron Atom Substitution prior to Completing the Endohedral B@Al<inf>12</inf><sup>-</sup> Superatom

    Inoue T., Hatanaka M., Nakajima A.

    Journal of the American Chemical Society （American Chemical Society)  145 （ 42 ） 23088 - 23097 2023.10

    Research paper (scientific journal), Joint Work, Accepted,  ISSN  00027863

    　View Summary

    Elemental substitution and doping validate the optimization of chemical and physical properties of functional materials, and the composition ratio of the substituting atoms generally determines their properties by changing their geometric and electronic structures. For atomically precise nanoclusters (NCs) consisting of countable atom aggregates, the composition can be controlled accurately to provide an ideal model to study the heteroatom substitution effects. Since aluminum (Al) and boron (B) both belong to group 13 in the periodic table, the effect of B atom substitution on Aln NCs can be investigated while maintaining the total number of valence electrons in AlnBm NCs. In this study, oxidative reactivities of small Al NCs with B atom substitution are studied for AlnBm NCs (m = 1, n = 6-14 and m = 2, n = 11) supported on organic surfaces by using X-ray photoelectron spectroscopy and oxygen molecule (O2) exposure measurements. Before completing the endohedral B@Al12- superatomic NC, one B atom substitution in Al NCs (AlnB) enhances oxidative reactivities 3-20 times compared to those of Aln+1, particularly for n ≤ 11. When one Al atom of Al12B is further substituted by a B atom to form Al11B2, the reactivity drastically increases (6.6 × 102 times), showing that the B atom substitution makes the NC chemically active or inactive geometrically depending on the exohedral or endohedral site for the B atom in the Al NC. In addition, density functional theory calculations show that the electronegative B atom contributes to forming a locally positive Al site to facilitate O2 adsorption except in Al12B, in which the B atom is geometrically shielded by the surface of the Al12 cage in B@Al12

  • Two-Photon Photoemission Spectroscopy and Microscopy for Electronic and Plasmonic Characterizations of Molecularly Designed Organic Surfaces

    Shibuta M., Nakajima A.

    The Journal of Physical Chemistry Letters （American Chemical Society)  14 （ 13 ） 3285 - 3295 2023.04

    Research paper (scientific journal), Joint Work, Accepted

    　View Summary

    Functional surfaces decorated with organic molecules and/or nanoclusters (NCs) composed of several tens of atoms are promising for use in future photoelectronic substrates, whose functionalities are governed by molecular local electronic/plasmonic excitations at the interfaces. Here, we combine two-photon photoemission spectroscopy (2P-PES) and microscopy (2P-PEEM) to investigate the local excited-state dynamics at organic surfaces functionalized with NCs. The 2P-PES and 2P-PEEM for organic fullerene (C60) layers on graphite and Au substrates demonstrated photophysical characterization of electronic and plasmonic properties, including propagating surface plasmon polaritons (SPPs). The SPP propagation at the Au interface buried by overlayered C60 can be visualized by Agn NC deposition, which enhances plasmon-induced hot electrons, where the threshold number of Ag atoms (n ≥ 9) for the plasmonic response is revealed by the size dependence of 2P-PES for Agn NCs on C60 layers.

  • Bridging the gas and condensed phases for metal-atom encapsulating silicon- and germanium-cage superatoms: electrical properties of assembled superatoms

    Yokoyama T., Nakajima A.

    Physical Chemistry Chemical Physics （Royal Chemical Society)  25 （ 14 ） 9738 - 9752 2023.03

    Research paper (scientific journal), Joint Work, Last author, Corresponding author, Accepted,  ISSN  14639076

    　View Summary

    With the development of nanocluster (NC) synthesis methods in the gas phase, atomically precise NCs composed of a finite number of metal and semiconductor atoms have emerged. NCs are expected to be the smallest units for nanomaterials with various functions, such as catalysts, optoelectronic materials, and electromagnetic devices. The exploration of a stable NC called a magic number NC has revealed a couple of important factors, such as a highly symmetric geometric structure and an electronic shell closure, and a magic number behavior is often enhanced by mixing additional elements. A synergetic effect between geometric and electronic structures leads to the formation of chemically robust NC units called superatoms (SAs), which act as individual units assembled as thin films. The agglomeration of non-ligated bare SAs is desirable in fabricating the assembled SAs associated with intrinsic SA nature. The recent development of an intensive pulsed magnetron sputtering method opens up the scalable synthesis of SAs in the gas phase, enabling the fabrication of SA assembly coupled with the non-destructive deposition of a soft-landing technique. This perspective describes our recent progress in the investigation of the formation of binary cage SA (BCSA) assembled thin films composed of metal-atom encapsulating silicon-cage SAs (M@Si16) and germanium-cage SAs (M@Ge16), with a focus on their electrical properties associated with a conduction mechanism toward the development of new functional nanoscale materials.

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Papers, etc., Registered in KOARA 【 Display / hide 】

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Reviews, Commentaries, etc. 【 Display / hide 】

  • Fabrication method for nanocluster superatoms with high-power impulse magnetron sputtering

    Tsunoyama Hironori, Tona Masahide, Tsukamoto Keizo, Nakajima Atsushi

    Journal of the Vacuum Society of Japan 60 ( 9 ) 352 - 361 2017

    Article, review, commentary, editorial, etc. (scientific journal), Joint Work,  ISSN  1882-2398

    　View Summary

    <p>Intensive ion source for single-size nanoclusters was developed on the basis of high-power impulse magnetron sputtering (HiPIMS) technique combined with a low-pressure, low-temperature gas flow reactor. The nanocluster source exhibits superior characteristics originating from pulsed, high-power sputtering compared to conventional direct-current sputtering; (1) enhanced ion intensities, (2) fascicle tuning of nanocluster sizes, and (3) enhanced selectivity of stable, magic nanoclusters. The metallic (silver, platinum, and palladium) and binary (transition-metal and silicon) nanocluster ions in the size range of several to one hundred atoms can be generated with ion current of 100 pA to 10 nA (108 to 1011 nanoclusters/sec). The growth mechanism of nanoclusters in the source was also explained by the nucleation theory.</p>

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Presentations 【 Display / hide 】

  • Monodispersed Immobilization and Island Formation of M@Si16 Superatom

    NAKAJIMA ATSUSHI

    The Cluster Surface Interactions 2016 Workshop (Argonne National Laboratory) , 

    2016.06
    , 

    Oral presentation (invited, special)

  • Alkali-Like Binary Superatom of a Ta-Encapsulating Si16 Cage

    NAKAJIMA ATSUSHI

    Symposium on Size Selected Clusters (S3C) 2016 (Davos, Switzerland) , 

    2016.03
    , 

    Oral presentation (keynote)

  • Nanocluster superatom formation using ion source based on high-power impulse magnetron sputtering

    NAKAJIMA ATSUSHI

    Pacifichem 2015 (Honolulu, Hawaii, USA) , 

    2015.12
    , 

    Oral presentation (invited, special)

  • Formation of binary superatom nanocluster monolayer

    NAKAJIMA ATSUSHI

    XXIV International Materials Research Congress (IMRC) on Clusters & Nanostructures (Cancun, Mexico) , 

    2015.08
    , 

    Oral presentation (invited, special)

  • Formation of Superatom Monolayer Using Nanocluster Ion Source Based on High-Power Impulse Magnetron Sputtering

    NAKAJIMA ATSUSHI

    2015 Gordon Research Conference (GRC) “Clusters and Cluster Assembled Materials” (Girona, Spain) , 

    2015.07
    , 

    Oral presentation (invited, special)

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Research Projects of Competitive Funds, etc. 【 Display / hide 】

  • 次世代光磁気材料を指向したナノデザイン制御

    2002.10
    -
    2007.09

    Keio University, Kobe University, Osaka University, Hiroshima University, University of Chicago, Argonne National Laboratory, -, Research grant, No Setting

  • Development of Sub-nanosized Aggregates Having Novel Optical Properties

    1997.07
    -
    2003.03

    Keio University, Kobe University, Tohoku University, Institute for Molecular Science, “Research for the Future (RFTF)” of the Japan Society for the Promotion of Science, Research grant, No Setting

    　View Summary

    We have successfully established several new methodologies to generate sub-nanosized aggregates having novel optical properties, and revealed fundamental properties of their electronic and geometrical structures as well as molecular aggregates bridging between gas and liquid/solid phases. New areas of “gas-phase organometallic chemistry” have been developed to create and to design new optoelectronic materials with our proposed soft-landing method.

  • Study of Magnetic Bottle Electron Spectrometer and Their Application

    1999.04
    -
    2004.03

    Keio University, Special Coordination Funds for the promotion of Science and Technology, Research grant, No Setting

  • ナノ生体触媒の創成を指向したニトロゲナーゼ酵素の鉄－硫黄活性中心のデザイン制御

    2003.04
    -
    2006.03

    慶應義塾大学, Grant-in-Aid for Scientific Research, Research grant, No Setting

  • 気相多元系合金クラスターの基板担持による触媒機能と電子物性の研究

    2001.04
    -
    2003.03

    Grant-in-Aid for Scientific Research, Research grant, No Setting

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Intellectual Property Rights, etc. 【 Display / hide 】

  • ナノクラスター生成装置

    Date applied： 2013－112995  2013.05 

    Patent, Joint

  • 多重レーザー照射による液滴試料の粉砕法

    Date applied： 2012-162131  2012.07 

    Patent, Joint

  • “マイクロミキサー、マイクロミキサーエレメント及びその製造方法”

    Date applied： 2012-0989620  2012.04 

    Patent, Joint

  • ナノクラスター分散液、ナノクラスター膜、ナノクラスター分散体の製造方法およびナノクラスター分散液の製造装置

    Date applied： 2015－160680   

    Patent, Joint

  • マイクロミキサー、マイクロミキサーエレメントおよびその製造方法

    Date applied： 2016-033117   

    Patent, Joint

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Awards 【 Display / hide 】

  • 令和5年度　文部科学大臣表彰　科学技術賞　研究部門

    2023.04, 文部科学省, 複合ナノクラスター精密担持法によるナノ機能表面化学の研究

    Type of Award： Other

  • Humboldt Research Award

    2020.05, アレクサンダー・フンボルト財団

    Type of Award： International academic award (Japan or overseas)

  • 分子科学会賞

    2018.08, 分子科学会, 複合ナノクラスター科学の開拓－気相化学からナノ機能表面化学へ

    Type of Award： Award from Japanese society, conference, symposium, etc.

  • 田中貴金属研究財団 シルバー賞

    2017.03

    Type of Award： Award from publisher, newspaper, foundation, etc.

  • The Chemical Society of Japan Award for Creative Work for 2008

    NAKAJIMA ATSUSHI, 2009.03, 社団法人　日本化学会, 複合クラスターを用いたナノスケール物質群の創製とその電子物性の解明

    Type of Award： Award from Japanese society, conference, symposium, etc.

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Courses Taught 【 Display / hide 】

  • STATISTICAL THERMODYNAMICS (BASIC PHYSICAL CHEMISTRY 1)

    2024

  • STATISTICAL THERMODYNAMICS

    2024

  • STATISTICAL CHEMICAL THERMODYNAMICS EXERCISE

    2024

  • SEMINAR IN CHEMISTRY

    2024

  • QUANTUM STATISTICAL CHEMISTRY (PHYSICAL CHEMISTRY 2)

    2024

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Memberships in Academic Societies 【 Display / hide 】

  • 分子科学会, 

    2004.09
    -
    Present

  • ナノ学会, 

    2004.05
    -
    2020.03

  • 日本物理学会, 

    1984.03
    -
    Present

  • 日本化学会, 

    1983.10
    -
    Present
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Committee Experiences 【 Display / hide 】

  • 2020.06
    -
    Present

    理事, 日本化学会

  • 2008.09
    -
    2010.08

    会長, 分子科学会

  • 2006.08
    -
    Present

    連携会員, 日本学術会議

  • 2004.09
    -
    2006.08

    Committee Chair, 分子科学研究会

  • 2004.05
    -
    2020.03

    Director, ナノ学会

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