圧力で光励起状態分子の分裂を操る！柔らかな分子で拓く次世代エネルギー変換材料～静水圧によって一重項分裂を自在に制御するソフトマテリアルの新設計指針を提案～

2025-10-24 九州大学

SF光反応過程の圧力制御

＜関連情報＞

• https://www.kyushu-u.ac.jp/ja/researches/view/1352
• https://www.kyushu-u.ac.jp/f/63726/25_1024_02.pdf
• https://pubs.rsc.org/en/content/articlelanding/2025/sc/d5sc04791a

静水圧によって分子内シングレット・フィッションを能動的に制御できる重要な分子設計 Critical molecular design that can actively control intramolecular singlet fission by hydrostatic pressure

Rintaro Ogawa,Tomokazu Kinoshita,Tomoya Kuwabara,Hayato Sakai, Makoto Harada,Taku Hasobe and Gaku Fukuhara
Chemical Science  Published:13 Oct 2025
DOI:https://doi.org/10.1039/D5SC04791A

Abstract

The active control of singlet fission (SF) by external stimuli presents a major challenge in current chemistry, although it is yet in the initial stages. In this study, we synthesized a series of SF-active chromophore pentacene dimers connected by the flexible linkers and investigated the ground- and excited-state properties, under hydrostatic pressure as an external stimulus. The flexibilities of the linkers were elucidated by the density functional theory. Hydrostatic pressure-UV/vis and hydrostatic pressure-circular dichroism spectroscopies showed the absence of a ground-state conformational change, indicating that the active switching of SF observed in this study comes from the excited-state dynamics. The hydrostatic pressure-fluorescence lifetime and hydrostatic pressure-nanosecond transient absorption measurements revealed the active inversion of SF process (acceleration vs. deceleration) and independent triplet (T₁) formation, in addition to the shortened T₁ lifetimes and non-decreasing T₁ quantum yields with elevating hydrostatic pressure. This study offers a valuable guideline through the critical molecular design revealed herein for further developing smart SF-controllable soft materials induced by hydrostatic pressure stimulations.