摘要
研究了三种苯并－１５－冠－５与Ｅｕ（Ⅲ）配合物在乙腈中的荧光性质．发现对Ｅｕ（Ⅲ）荧光的猝灭能力是苯并－１５－冠－５（Ｉ_ａ）＞４＇－硝基苯并－１５－冠－５（Ｉ_ｅ）＞４＇－甲酰基苯并－１５－冠－５（Ｉ_ｂ）。且Ｉｂ与Ｅｕ（Ⅲ）之间存在能量传送作用．首次提出利用￣５Ｄｏ－￣７Ｆ_２／￣５Ｄｏ－￣７Ｆ_１（ＥＴＦＰ／ＭＴＦＰ）之比可以反映出苯环上４＇－取代基的不同对Ｅｕ（Ⅲ）对称性的影响，且这个比值与能量传递无关．
Abstract The fluorescene characteristics of three guest-host complexes formed by 4'-substitued benzo-15crown-5 and (Ⅲ) were reported.The sequence of the quenching ability of crown ethers to the emission of excised Eu (Ⅲ) was found to be benzo-15-crown-5 (I_s )>4'- ntiro-benzo-15-crown (I_c )>4'formyl-benzo-15-crown-5 (I_b) and an enetgy transfer process from I_b to Eu(Ⅲ) was confirmed. The utilization of the ratio of ￣5D_0-￣7F_2/￣5D_0-￣7F_1 (ETFP/MTFP) as a measure of the substituents on benzo-crown ethers upon the fluorasence features due to the change of symmetry of the microenvironment of Eu(Ⅲ) was first proposed .
