Acta Chim. Sin.

Two kinds of Eu(III) complexes with mixed ligands of alpha - thenoyltrifluoroacetone (HTTA) and cryptand [2.2] (C[2.2]) were prepared: 2Eu(TTA)(3) . 2HTTA . C[2.2](A) and 2Eu .(TTA)(3) . C[2.2](B). The observed intensity of luminescence of the complexes A and B is 13.3 and 3.7 times respectively greater than that of the complex Eu(TTA)(3) . 2H(2)O(C) under the same experimental conditions. The enhancement of luminescence intensity is the results of increasing the efficiency of the intermolecular energy transfer and preventing coordinational H2O from quenching luminescence of the rare earth ions by adding. of cryptand[2.2]. The thermal properties and their structural characters of these complexes are also described basing on the results of TG and DTA, as well as the results of FT - IR and FT - Raman spectra