Systematic study of the luminescent europium-based nonanuclear clusters with modified 2-hydroxybenzophenone ligands.
The reaction of 2-hydroxybenzophenone derivatives with europium ions has afforded a new family of luminescent nonanuclear Eu(III) clusters. Crystal structure analysis of the clusters reveals that the metal core comprises two vertex-sharing square pyramidal units. Most of these complexes show emissions typical of Eu(3+) ion under visible light excitation (400-420 nm) at room temperature. Photophysical characterization and DFT study reveal a correlation between luminescent efficiencies of Eu(III) complexes and the electronic features of the ligands, which can be tuned by the nature of substituents in the 4-position of the ligands. The ligands with a fluorine substituent possess more suitable triplet energy levels, resulting in more intensive luminescence.
The College of Chemistry and Molecular Engineering, Zhengzhou University , Zhengzhou, 450052, P. R. China.
Bin
B
Zhang
Ting
T
Xiao
Chunmei
C
Liu
Qian
Q
Li
Yanyan
Y
Zhu
Mingsheng
M
Tang
Chenxia
C
Du
Maoping
M
Song