title: Aggregation induced blue-shifted emission--the molecular picture from a QM/MM study.
abstract: In general, optical emission in the solid-state is red-shifted with respect to the solution phase. A series of recently synthesized compounds exhibits aggregation induced blue-shifted emission (AIBSE) phenomena. By employing a polarizable continuum model (PCM) and a hybrid quantum mechanics/molecular mechanics (QM/MM) approach, we investigate the excited-state electronic structures of some typical AIE-active molecules both in solvents and in aggregates at the time-dependent density functional theory (TD-DFT) level. It is found that the AIBSE phenomena originate from the smaller reorganization energy in aggregates than in the solution phase, as evidenced through the restricted structural relaxation, planarization in the excited state, and freezing of low-frequency out-of-plane twists in the transition state.
authors: Key Laboratory of Organic OptoElectronics and Molecular Engineering, Department of Chemistry, Tsinghua University, Beijing 100084, P. R. China. zgshuai@tsinghua.edu.cn.
authors: Qunyan
authors: Q
authors: Wu
authors: Tian
authors: T
authors: Zhang
authors: Qian
authors: Q
authors: Peng
authors: Dong
authors: D
authors: Wang
authors: Zhigang
authors: Z
authors: Shuai
mesh_terms: D000873:Anthracenes / Q000737:chemistry*; D002070:Butadienes / Q000737:chemistry*; D008958:Models, Molecular; D015394:Molecular Structure; D011719:Pyrazines / Q000737:chemistry*; D011789:Quantum Theory
chemical_list: D000873:Anthracenes; D002070:Butadienes; D011719:Pyrazines