title: Solvent-dependent intramolecular charge transfer delocalization/localization in multibranched push-pull chromophores.
abstract: The effect of the solvent polarity on excitation delocalization/localization in multibranched push-pull chromophores has been thoroughly explored by combining steady state absorption and fluorescence, as well as femtosecond transient spectral measurements. We found that the excited-state relaxations of the push-pull chromophores are highly dependent on both solvent polarity and the polar degree of the excited intramolecular charge transfer states. The symmetry of multibranched chromophores is preserved in less polar solvents, leading to excitation delocalization over all of the branches because of the negligible solvent reaction field. In contrast, symmetry is broken for multibranched chromophores in more polar solvents because of intense solvent reaction field, and the excitation is consequently localized on one of the dipolar molecular branches. The results provide a fundamental understanding of solvent-dependent excitation delocalization/localization properties of the multibranched chromophores for the potential applications in nonlinear optics and energy-harvesting applications.
authors.affiliation: Beijing National Laboratory for Molecular Sciences (BNLMS) and Key Laboratory of Photochemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, People's Republic of China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Li
authors.affiliation: Beijing National Laboratory for Molecular Sciences (BNLMS) and Key Laboratory of Photochemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, People's Republic of China.
authors.forename: Meng
authors.initials: M
authors.lastname: Zhou
authors.affiliation: Beijing National Laboratory for Molecular Sciences (BNLMS) and Key Laboratory of Photochemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, People's Republic of China.
authors.forename: Yingli
authors.initials: Y
authors.lastname: Niu
authors.affiliation: Beijing National Laboratory for Molecular Sciences (BNLMS) and Key Laboratory of Photochemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, People's Republic of China.
authors.forename: Qianjin
authors.initials: Q
authors.lastname: Guo
authors.affiliation: Beijing National Laboratory for Molecular Sciences (BNLMS) and Key Laboratory of Photochemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, People's Republic of China.
authors.forename: Andong
authors.initials: A
authors.lastname: Xia
mesh_terms: D019281:Dimerization; D005453:Fluorescence; D005663:Furans / Q000737:chemistry; D008956:Models, Chemical; D011108:Polymers / Q000737:chemistry*; D011789:Quantum Theory; D012997:Solvents / Q000737:chemistry*; D013057:Spectrum Analysis; D014050:Toluene / Q000737:chemistry
chemical_list: D005663:Furans; D011108:Polymers; D012997:Solvents; D014050:Toluene; C018674:tetrahydrofuran