Participating Group (2020-2021)
Rational Creation of Mechanical-Stimuli-Responsive Soft Crystals and Sophistication of Quantitative Analytical Method
Co-Researcher: Izuru Kawamura(Graduate School of Engineering Science, Yokohama National University, Associate Professor)
Mechanochromic luminescence, that can change the emission properties in response to mechanical stimuli such as grinding, is one of the typical stimuli-responsive behaviors exhibited by soft crystals. In the previous work, this researcher has succeeded in developing an apparatus that can quantitatively evaluate the responsiveness of soft crystals to mechanical stimuli. In addition, a new design guideline for mechanochromically luminescent materials has been established based on the creation of two-component organic soft crystals.
In this study, this researcher will realize the development of structural motifs and mechanistic analyses of soft crystals. Specifically, (1) a rational method to control the mechanical-stimuli-responsiveness will be established by forming complexes between novel luminescent host molecules and guest molecules. (2) Energy diagrams of mechanochromic luminescence will be clarified by the quantitative analysis of the responsiveness of soft crystals to mechanical stimuli. In addition, the quantitative analysis of mechanical-stimuli-responsive behaviors of various soft crystals will be examined thorough collaborative researches, which will lead to a comprehensive understanding of the responsiveness of soft crystals to mechanical stimuli.
Participating Group (2018-2019)
Creation of Multi-color Emissive Organic Soft Crystals and Quantitative Analysis of Mechanical Stimuli-responsive Property
Co-Researcher: Izuru Kawamura (Graduate School of Engineering Science, Yokohama National, Associate Professor)
Soft crystals that can change their emission colors in response to mechanical stimuli such as “grinding” are a part of the central research subjects of this area. The principal investigator has already succeeded in the development of mechanochromic luminescent organic soft crystals that exhibit “self-recovery of changed emission color” or “two-step emission color change in response to the strength of grinding force”. In this study, we establish a quantitative analysis method for the strength of mechanical stimuli required for the emission color change and a new creation method for the multi-color emissive mechanochromic luminescent soft crystals. These studies would provide mechanistic insights and novel motifs of mechanochromic luminescent organic soft crystals. Specifically, we will work on (1) the quantification of “grinding force” by a device designed and developed by ourselves, and (2) the creation of multi-color emissive soft crystals by utilizing intermolecular interactions of different molecules. We also aim to comprehensively understand this phenomenon by the quantification of the strength of mechanical stimuli required for other soft crystals through collaborative researches.
- "Luminescent polymorphic crystals: mechanoresponsive and multicolor-emissive properties" *S. Ito, CrystEngComm, 24, 1112-1126 (2022).(Cover)DOI: 10.1039/D1CE01614H
- "Mechanochromic luminescence of soft crystals: Recent systematic studies in controlling the molecular packing and mechanoresponsive properties" *S. Ito, J. Photochem. Photobiol., C, 51, 100481 (2022).
- “In Situ Exploration of Stimulus-Induced Emission Changes in Mechanochromic Dyes” M. Yamashita, S. Nagai, *S. Ito, *T. Tachikawa, J. Phys. Chem. Lett., 12, 7826-7831 (2021).(領域内共同研究 A03公募 立川)
- “Mechano- and Thermo-responsive Luminescence of Crystalline Thienylbenzothiadiazole Derivatives: Stepwise Hypsochromic Switching of Near-Infrared Emission” R. Yoshida, *T. Tachikawa, *S. Ito, Cryst. Growth Des., 22, 547-558 (2022).(領域内共同研究 A03公募 立川)
- “Mechanochromic Luminescence (MCL) of Purely Organic Two-Component Dyes: Wide-Range MCL over 300 nm and Two-Step MCL by Charge-Transfer Complexation” *S. Ito, R. Sekine, M. Munakata, M. Yamashita, *T. Tachikawa, Chem. – Eur. J., 27, 13982-13990 (2021).(Cover)(領域内共同研究 A03公募 立川)
- “Mechanochromic Luminescence and Solid-State Circularly Polarized Luminescence of a Chiral Diamine-Linked Bispyrene” *S. Ito, R. Sekine, M. Munakata, M. Asami, T. Tachikawa, D. Kaji, K. Mishima, *Y. Imai, ChemPhotoChem, 5, 920-925 (2021).(Front Cover)(領域内共同研究 A03公募 立川、A03公募 今井)
- “Multi-color mechanochromic luminescence of three polymorphic crystals of a donor–acceptor-type benzothiadiazole derivative” *S. Ito, S. Nagai, T. Ubukata, T. Tachikawa, CrystEngComm, 23, 5899-5907 (2021).(領域内共同研究 A03公募 立川)DOI: 10.1039/D1CE00445J
- “Tunable mechanochromic luminescence via surface protonation of pyridyl-substituted imidazole crystals” R. Kubota, Y. Yuan, R. Yoshida, *T. Tachikawa, *S. Ito, Mater. Adv., (2022).(領域内共同研究 A03公募 立川)DOI: 10.1039/D2MA00256F
- “Extension of the mechanoresponsive luminescence shift via formation of a doped organic crystal” R. Yoshida, *T. Tachikawa, *S. Ito, Chem. Commun., (2022).(領域内共同研究 A03公募 立川)DOI: 10.1039/D2CC00741J
- "Recent Advances in Mechanochromic Luminescence of Organic Crystalline Compounds" *S. Ito, Chem. Lett., 50, 649-660 (2021).DOI: 10.1246/cl.200874
- "Two types of two-step mechanochromic luminescence of phenanthroimidazolylbenzothiadiazoles" S. Takahashi, S. Nagai, M. Asami, *S. Ito, Mater. Adv., 1, 708-719 (2020).DOI: 10.1039/D0MA00198H
- "Sequential Halochromic/mechanochromic Luminescence of Pyridyl-substituted Solid-state Emissive Dyes: Thermally Controlled Stepwise Recovery of the Original Emission Color" S. Ito, C. Nishimoto and S. Nagai, CrystEngComm, 2019, 21(38), 5685–5854.(Cover)DOI: 10.1039/C9CE01037H
- "Switching the Direction of Mechano-responsive Emission Color Change of Triphenylimidazolylbenzothiadiazole" S. Ito, S. Nagai, T. Ubukata and M. Asami, Chemistry Letters, 2019, 48(12), 1492–1495.DOI: 10.1246/cl.190680
- "Tunable Mechanochromic Luminescence of 2-Alkyl-4-(pyren-1-yl)thiophenes: Controlling the Self-recovering Properties and the Range of Chromism" M. Ikeya, G. Katada and S. Ito, Chemical Communications, 2019, 55(82), 12296–12299.(Outside Back Cover、プレスリリース).DOI: 10.1039/C9CC06406K
- "Efficient and Versatile Mechanochromic Luminescence of Phenanthroimidazolylbenzothiadiazoles: Tricolor Switching and Directional Control over the Chromism" S. Nagai, M. Yamashita, T. Tachikawa, T. Ubukata, M. Asami, S. Ito, Journal of Materials Chemistry C, 2019, 7, 4988-4998.(Inside Back Cover、領域内共同研究 A03公募 立川)DOI: 10.1039/C9TC00157C
- "Tricolor mechanochromic luminescence of an organic two-component dye: visualization of a crystalline state and two amorphous states" S. Ito, G. Katada, T. Taguchi, I. Kawamura, T. Ubukata, M. Asami, CrystEngComm, 2019, 21, 53-59.DOI: 10.1039/C8CE01698D
- "Mechanochromic luminescence of organic two-component luminophores" S. Ito, International Conference on Photochemistry (ICP2021) (Online, 22 July, 2021)
- "Mechanochromic luminescence of two-component solid-state fluorophores" S. Ito, The International Chemical Congress of Pacific Basin Societies 2021 (Pacifichem 2021) (Online, 17 December, 2021)
- "Tunable mechanochromic luminescence of organic two-component dyes composed of dibenzofuran-based bispyrene and electron-deficient dyes" S. Ito, R. Sekine, M. Munakata, M. Yamashita, T. Tachikawa, ACS Spring 2022 (Online, 21 March, 2022)
- "Wide-Range and Two-Step Mechanochromic Luminescence of Organic Two-Component Dyes" S. Ito, R. Sekine, M. Munakata, M. Yamashita, T. Tachikawa, 11th Asian Photochemistry Conference (APC2021) (Online, 4 November, 2021)
- " Crystal-to-Amorphous Phase Transitions of Mechanochromically Luminescent Organic Molecules" S. Ito (Invited), The 101st CSJ Annual Meeting, Luminescence Chemistry Ensemble: From the Aggregate Model to Amorphous Solid (Online, Mar. 20, 2021)