Molecular Spectroscopy Laboratory, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.
Ultrafast Spectroscopy Research Team, RIKEN Center for Advanced Photonics (RAP), 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.
Chem Commun (Camb). 2022 Jan 20;58(7):961-964. doi: 10.1039/d1cc06093g.
An ultrafast spectroscopic study was carried out for a photoisomerizable, rotaxane-based molecular shuttle, in which photoisomerization of the azobenzene moiety of the thread-like guest drives a shuttling motion of a cyclodextrin host. Femtosecond upconversion and time-resolved absorption measurements revealed distinct S dynamics with time constants of 1.2 and 17 ps. Both time constants are smaller when the cyclodextrin host is absent, implying that, within the S state, there are mutiple barriers to the isomerization and subsequent shuttling, due to steric interference from the cyclodextrin.
进行了超快光谱研究一种光致异构的，轮烷基分子梭，其中线状客体的偶氮苯部分的光致异构驱动环糊精主体的穿梭运动。飞秒上转换和时间分辨吸收测量揭示了具有 1.2 和 17 ps 时常数的独特 S 动力学。当环糊精主体不存在时，两个时常数都较小，这意味着在 S 态下，由于环糊精的空间位阻，异构化和随后的穿梭存在多个障碍。
