title: Photomodulated Supramolecular Chirality in Achiral Photoresponsive Rodlike Compounds Nanosegregated from the Helical Nanofilaments of Achiral Bent-Core Molecules.
abstract: We prepared a nonchiral mixture of achiral bent-core molecules and photoresponsive rodlike liquid crystalline (LC) molecules. With the help of the isothermal photochemical nematic (N)-isotropic (Iso) phase transition of the photoresponsive rodlike LC molecules, the corresponding phase transition from a dark conglomerate BX phase to another distinguishable dark conglomerate B4 phase took place in the mixture. A large circular dichroism (CD) signal originating from supramolecular chirality was detected in the initial BX phase. On the other hand, the detected CD signal was decreased in the B4 phase after UV irradiation. Interestingly, the decreased CD signal could be reverted to the initial CD signal with visible irradiation. This chiroptical process revealed in this work was stable and reversible and thus opens up the possibility of practical applications such as rewritable optical storage.
authors.affiliation: Department of Advance Materials Engineering for Information and Electronics, Kyung Hee University , Yongin-shi, Gyeonggi-do 446-701, Korea.
authors.forename: Kibeom
authors.initials: K
authors.lastname: Kim
authors.affiliation: Graduate School of Nanoscience and Technology and KINC, KAIST , Daejeon 305-701, Korea.
authors.forename: Hanim
authors.initials: H
authors.lastname: Kim
authors.affiliation: Department of Advance Materials Engineering for Information and Electronics, Kyung Hee University , Yongin-shi, Gyeonggi-do 446-701, Korea.
authors.forename: Seong-Yong
authors.initials: SY
authors.lastname: Jo
authors.affiliation: Physicochemical Soft Matter Research Unit, RIKEN Center for Emergent Matter Science (CEMS) , 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.
authors.forename: Fumito
authors.initials: F
authors.lastname: Araoka
authors.affiliation: Graduate School of Nanoscience and Technology and KINC, KAIST , Daejeon 305-701, Korea.
authors.forename: Dong Ki
authors.initials: DK
authors.lastname: Yoon
authors.affiliation: Department of Advance Materials Engineering for Information and Electronics, Kyung Hee University , Yongin-shi, Gyeonggi-do 446-701, Korea.
authors.forename: Suk-Won
authors.initials: SW
authors.lastname: Choi
keywords: bent-core; chirality; chiroptical switching; circular dichroism; helical nanofilament; liquid crystal