ja7b08592_si_004.cif (790.94 kB)
Why Do Simple Molecules with “Isolated” Phenyl Rings Emit Visible Light?
dataset
posted on 2017-10-24, 00:00 authored by Haoke Zhang, Xiaoyan Zheng, Ni Xie, Zikai He, Junkai Liu, Nelson L. C. Leung, Yingli Niu, Xuhui Huang, Kam Sing Wong, Ryan T. K. Kwok, Herman H. Y. Sung, Ian D. Williams, Anjun Qin, Jacky W. Y. Lam, Ben Zhong Tangπ-Bonds connected with aromatic
rings were generally believed
as the standard structures for constructing highly efficient fluorophores.
Materials without these typical structures, however, exhibited only
low fluorescence quantum yields and emitted in the ultraviolet spectral
region. In this work, three molecules, namely bis(2,4,5-trimethylphenyl)methane,
1,1,2,2-tetrakis(2,4,5-trimethylphenyl)ethane, and 1,1,2,2-tetraphenylethane,
with nonconjugated structures and isolated phenyl rings were synthesized
and their photophysical properties were systematically investigated.
Interestingly, the emission spectra of these three molecules could
be well extended to 600 nm with high solid-state quantum yields of
up to 70%. Experimental and theoretical analyses proved that intramolecular
through-space conjugation between the “isolated” phenyl
rings played an important role for this abnormal phenomenon.