The crystal structure of QEu(TTA)~4.H~2O [Q=3, 6-di(dimethylamine)- diphenyliodonium, TTA=thenoyltrifluoroacetonate] was determined. The crystal is monoclinic with space group P2~1/n, a=1.4206(6), b=2.761(1) , c=1.4658(3)nm, β=100.40(2)ⅲ, Z=4, the final R is 0.079. The luminescence spectra of the title complex indicate one Eu(Ⅲ) site in the complex. Combining the results of luminescence spectra with that of crystal determination, the local symmetry of Eu(Ⅲ) site is C~1. Investigation of radical photopolymerization shows that some amount of title complex can increase the polymerization rate through oxiding ketyl radical.

Key words: FLUOROSPECTROPHOTOMETRY, CRYSTAL STRUCTURE, 2-THENOYL- TRIFLUORO-ACETONE, IODINE, COMPLEX COMPOUNDS, CRYSTAL STRUCTURE DETERMINATION, CRYSTALS, FREE REDICAL POLYMERIZATION, INITIATION