文献类型：期刊文献

英文题名：Switching Singlet Exciton to Triplet for Efficient Pure Organic Room-Temperature Phosphorescence by Rational Molecular Design

作者：Ma, Liangwei[1,2];Liu, Yiwei[1,2];Tian, He[1,2];Ma, Xiang[1,2]

机构：[1]East China Univ Sci & Technol, Key Lab Adv Mat, Shanghai 200237, Peoples R China;[2]East China Univ Sci & Technol, Feringa Nobel Prize Scientist Joint Res Ctr, Frontiers Sci Ctr Materiobiol & Dynam Chem, Sch Chem & Mol Engn, Shanghai 200237, Peoples R China

年份：2023

卷号：3

期号：7

起止页码：1835

外文期刊名：JACS AU

收录：WOS:【ESCI(收录号:WOS:001022342400001)】；

基金：We gratefully acknowledge the financial support from the National Key Research and Development Program of China (2022YFB3203500), NSFC (22125803 and 22020102006), project support by the Shanghai Municipal Science and Technology Major Project (Grant No. 2018SHZDZX03), Program of Shanghai Academic/Technology Research Leader (20XD1421300), China National Postdoctoral Program for Innovative Talents (BX20220106), China Postdoctoral Science Foundation (2022M721140), and Fundamental Research Funds for the Central Universities.

语种：英文

外文关键词：room-temperature phosphorescence; dark state; heavy-atom-free; phosphorescence quantum yield

摘要：The design and regulation of phosphors are attractivebut challengingbecause of the spin-forbidden intersystem crossing (ISC) process.Here, a new perspective on the enhancement of the ISC is proposedand demonstrated. Different from current strategies, the ISC yield(& phi;(ISC)) is enhanced by decreasing the fluorescenceradiative transition rate constant (k (F)) via rational molecular designing rather than boosting the spin-orbitcoupling by decorating the molecular skeleton with a heavy atom, heteroatom,or carbonyl. The k (F) of the designed moleculein this case is associated with the substituent position of the methoxygroup, which alters the distribution of the front orbitals. The S-0 & RARR; S-1 transition of these compounds evolvesfrom a bright state to a dark state gradually with the variation ofthe substituent position, accompanied by the decrease of k (F) and increase of & phi;(ISC). The fluorescenceemission is switched to phosphorescence emission successfully by regulatingthe k (F). This work provides an alternativestrategy to design efficient room-temperature phosphorescence material.