Sugiyama, Haruki



Faculty of Letters (Hiyoshi)


Assistant Professor (Non-tenured)/Research Associate (Non-tenured)/Instructor (Non-tenured)

Academic Degrees 【 Display / hide

  • 博士(理学), Tokyo Institute of Technology, Coursework, 2018.09

    Structure-Property Relationship of Multi-Chromic Metal Complexes with N-Salicylideneaminopyridine Ligands


Research Areas 【 Display / hide

  • Crystal engineering

  • Organic and hybrid materials

Research Keywords 【 Display / hide

  • X ray crystal structural analysis

  • Chromism

  • Organic crystal


Papers 【 Display / hide

  • Triplon band splitting and topologically protected edge states in the dimerized antiferromagnet

    Nawa K., Tanaka K., Kurita N., Sato T., Sugiyama H., Uekusa H., Ohira-Kawamura S., Nakajima K., Tanaka H.

    Nature Communications (Nature Communications)  10 ( 1 )  2019.12

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    © 2019, The Author(s). Search for topological materials has been actively promoted in the field of condensed matter physics for their potential application in energy-efficient information transmission and processing. Recent studies have revealed that topologically invariant states, such as edge states in topological insulators, can emerge not only in a fermionic electron system but also in a bosonic system, enabling nondissipative propagation of quasiparticles. Here we report the topologically nontrivial triplon bands measured by inelastic neutron scattering on the spin-1/2 two-dimensional dimerized antiferromagnet Ba2CuSi2O6Cl2. The excitation spectrum exhibits two triplon bands that are clearly separated by a band gap due to a small alternation in interdimer exchange interaction, consistent with a refined crystal structure. By analytically modeling the triplon dispersion, we show that Ba2CuSi2O6Cl2 is the first bosonic realization of the coupled Su-Schrieffer-Heeger model, where the presence of topologically protected edge states is prompted by a bipartite nature of the lattice.

  • In-Situ Photochromism Switching with Crystal Jumping through the Deammoniation of N-Salicylideneaniline Ammonium Salt

    Sugiyama H., Johmoto K., Sekine A., Uekusa H.

    Crystal Growth and Design (Crystal Growth and Design)  19 ( 8 ) 4324 - 4331 2019.08

    ISSN  15287483

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    Copyright © 2019 American Chemical Society. N-Salicylideneaniline (SA) derivatives are traditional organic photochromic compounds whose properties are closely related to their molecular conformations and crystal structures. We herein present the photochromic property switching phenomenon of SA ammonium salt crystals using a deammoniation reaction. The N-salicylidene-4-carboxyaniline ammonium salt crystal (1-Sα) was found to exhibit photochromism upon irradiation with UV light. Upon heating, 1-Sα desorbed ammonia gas and transformed into a nonionic SA crystal (1-N) with non-photochromic properties. Surprisingly, this phase transition induced the "jumping crystal" phenomenon. Thus, the crystal structures both before and after the phase transition were determined, and it was revealed that the switching phenomenon of photochromism (photochromism switching) was caused by the crystal structural and molecular conformational changes that took place upon deammoniation. In addition, 1-N reverted to 1-Sα by exposure to aqua-ammonia vapor for a few minutes. These results suggested that such SA crystals could be applicable as switching materials or chemical sensors. ©

  • Rhodium-Catalyzed Synthesis, Crystal Structures, and Photophysical Properties of [6]Cycloparaphenylene Tetracarboxylates

    Hayase N., Sugiyama H., Uekusa H., Shibata Y., Tanaka K.

    Organic Letters (Organic Letters)  21 ( 11 ) 3895 - 3899 2019.06

    ISSN  15237060

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    © 2019 American Chemical Society. The synthesis of C2-symmetrical [6]cycloparaphenylene (CPP) tetracarboxylates has been achieved via macrocyclization by the rhodium-catalyzed intermolecular stepwise cross-alkyne cyclotrimerization and subsequent reductive aromatization. The 1H NMR spectra of the thus-obtained C2-symmetrical [6]CPP-tetracarboxylates revealed that the rotation of unsubstituted benzene rings is slow at room temperature. These [6]CPPs formed columnar packing structures, and their absorption maxima were significantly blue-shifted compared to that of nonsubstituted [6]CPP due to the presence of four electron-withdrawing ester moieties.

  • Synthesis of Belt- A nd Möbius-Shaped Cycloparaphenylenes by Rhodium-Catalyzed Alkyne Cyclotrimerization

    Nishigaki S., Shibata Y., Nakajima A., Okajima H., Masumoto Y., Osawa T., Muranaka A., Sugiyama H., Horikawa A., Uekusa H., Koshino H., Uchiyama M., Sakamoto A., Tanaka K.

    Journal of the American Chemical Society (Journal of the American Chemical Society)   2019

    ISSN  00027863

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    Copyright © 2019 American Chemical Society. A belt-shaped [8]cycloparaphenylene (CPP) and an enantioenriched Möbius-shaped [10]CPP have been synthesized by high-yielding rhodium-catalyzed intramolecular cyclotrimerizations of a cyclic dodecayne and a pentadecayne, respectively. This Möbius-shaped [10]CPP possesses stable chirality and isolated with high enantiomeric purity. It is evident from the reaction Gibbs energy calculation that the above irreversible cyclotrimerizations are highly exothermic; therefore establishing that the intramolecular alkyne cyclotrimerization is a powerful route to strained cyclic molecular strips. ©

  • Reversible on/off switching of photochromic properties in: N-salicylideneaniline co-crystals by heating and humidification

    Sugiyama H., Johmoto K., Sekine A., Uekusa H.

    CrystEngComm (CrystEngComm)  21 ( 20 ) 3170 - 3175 2019

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    © The Royal Society of Chemistry 2019. N-Salicylideneaniline (SA) and its derivatives are known to exhibit photochromism, which is a reversible colour change induced by photo irradiation. Therefore, we performed on/off switching of the photochromic properties of an SA crystal by the hydration-dehydration phase transition. The photochromic properties of SA crystals are closely related to their crystal structures and molecular conformations. A monohydrated co-crystal (1H) of SA derivatives did not exhibit photochromism upon UV light irradiation. However, upon heating, 1H transformed to the anhydrous form 1A, which exhibited photochromism. Moreover, 1A re-hydrated to 1H under high humidity conditions, and the photochromic properties were switched off. Thus, the photochromic properties were reversibly switched on/off through the hydration-dehydration phase transition. X-ray crystal structural analyses revealed that the molecules adopted a planar (non-photochromic) conformation in 1H, but after dehydration, they changed to a non-planar (photochromic) conformation in 1A due to large crystal structure changes. Therefore, on/off switching of photochromism was clearly explained by the SA molecular conformation change. Additionally, proton transfer between SA and the co-former molecule was observed along with structural changes resulting from dehydration and hydration. This is the first report to switch the photochromic properties of SA crystals and explain the switching mechanism based on the crystal structure comparison. We intend to emphasize that the photochromism switching phenomena by external stimuli, namely heat and humidity, pave the way for utilizing these crystals in "smart materials".

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

Presentations 【 Display / hide

  • Color tuning of an organic photochromic compound by metal complex formation

    SUGIYAMA HarukiUEKUSA Hidehiro

    International Symposium on Pure & Applied Chemistry (ISPAC) 2017 (Ho Chi Minh City, Vietnam) , 2017.06, Oral Presentation(guest/special)

  • A novel dual-chromic crystal of a metal complex with Salicylideneaniline derivatives

    SUGIYAMA HarukiSEKINE Akiko(/)-#HRUEKUSA Hidehiro

    2016 Asian Crystallographic Association Meeting (AsCA2016) (Hanoi,Vietnam, Hanoi University of Science and Technology) , 2016.12, Poster (general), アジア結晶学連合

  • 有機クロミック化合物を配位子とした錯体の構造と特性

    SUGIYAMA HarukiSEKINE Akiko(/)-#HRUEKUSA Hidehiro

    日本結晶学会平成28年度年会 (茨城県立県民文化センター) , 2016.11, Poster (general), 一般社団法人 日本結晶学会

  • デュアルクロミズムを示すNi錯体の創製

    SUGIYAMA HarukiSEKINE Akiko(/)-#HRUEKUSA Hidehiro

    第6回CSJ化学フェスタ2016 (タワーホール船堀) , 2016.11, Poster (general), 公益社団法人日本化学会

  • A novel dual-chromic complex by using Salicylideneaniline derivatives

    SUGIYAMA HarukiSEKINE Akiko(/)-#HRUEKUSA Hidehiro

    Pacifichem2015, 2015.12, Poster (general), 日本化学会・アメリカ化学会・カナダ化学会・オーストラリア化学会・ニュージーランド化学会・韓国化学会・中国化学会

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