Construction of photo-triggered structural phase transition of organic molecular crystal and its extension to shape memory effect.

2023 Fiscal Year Final Research Report

• Project/Area Number: 22K14668
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 33010:Structural organic chemistry and physical organic chemistry-related
• Research Institution: Rikkyo University
• Principal Investigator: Nishimura Ryo 立教大学, 理学部, 助教 (00908634)
• Project Period (FY): 2022-04-01 – 2024-03-31
• Keywords: フォトクロミズム / ジアリールエテン / 有機結晶 / 光セルフヒーリング / 機械刺激

Outline of Final Research Achievements

In this research project, we focused on the creation of photoreactive molecular crystal showing shape memory effect and super elasticity.
We carried out the designing of molecules, synthesis, and crystallization to construct the functional crystal showing such functions, but we could not find such functional crystals. However, we found that the crystal showing elastically and plastically bending, in addition, its flexibility is switched by UV and visible light irradiation between flexible and brittle. These results provide new insights into molecular shape and crystal flexibility and are an important foothold toward building new functions for photofunctional organic crystal materials.

Free Research Field

有機光機能性材料

Academic Significance and Societal Importance of the Research Achievements

本課題の研究成果では、分子の形と結晶中での分子の配置や、それらと結晶の柔軟性に関する知見を得ることが出来た。また、光による結晶の柔軟性の可逆的なスイッチング現象を新たに見出し、そのメカニズムを解析すると、紫外光によって亀裂が入り脆性化、可視光によって亀裂が回復し柔軟性を取り戻していることが分かった。これらの成果は、次世代の機能性材料開発の足がかりとなり、持続可能な材料としての応用が期待される。