Multiple‐State Emissions from Neat, Single‐Component Molecular Solids: Suppression of Kasha's Rule
作者:Ya‐Hang Wu、Hongyan Xiao、Bin Chen、Richard G. Weiss、Yu‐Zhe Chen、Chen‐Ho Tung、Li‐Zhu Wu
DOI:10.1002/anie.202000608
日期:2020.6.15
single‐crystal structures, and theoretical calculations indicate that large energy gaps between S2 and S1 states (T2 and T1 states) as well as an abundance of intra and intermolecular hydrogen bonds suppress internal conversions of the upper excited states in the solids and make possible the fluorescence from S2 excited states (phosphorescence from T2 excited states). These results, including unprecedented
三个刚性和结构简单的杂环芪衍生物,(É)-3 ħ,3' ħ - [1,1'- biisobenzofuranylidene] -3,3'-二酮,(ë)-3-(3-氧代苯并[C]噻吩-1(3 ħ) -亚基)异苯并呋喃-1(3 ħ) -酮,和(ë)-3- ħ,3' ħ - [1,1'- bibenzo并[c] thiophenylidene] -3,3'-二酮,甚至在室温下在空气中,也被发现从上(S 2)和最低(S 1)单线态激发态以纯净的固相发出荧光。光物理研究,单晶结构和理论计算表明,S 2和S之间的能隙较大1态(T 2和T 1态)以及大量的分子内和分子间氢键抑制了固体中较高激发态的内部转化,并使来自S 2激发态的荧光(来自T 2激发态的荧光)成为可能。这些结果,包括来自纯固体中S 2状态的空前的荧光量子产率(2.3-9.6%),建立了一个独特的分子骨架,可通过“抑制” Kasha规则来实现上激发态的多色发射。