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合成了一个带有末端取代的能量给体－萘和能量受体－蒽的开链冠醚（ＤＳＡ）．吸收光谱表明两个发色团之间在基态时没有相互作用 选择性激发萘观察到萘的荧光强度下降，同时伴随着蒽的发射增强，表明发生了从萘至蒽的单重态－单重态能量转移．能量转移效率受溶剂极性的影响．可以认为在极性小的溶剂如苯中－ＯＣＨ２ＣＨ２Ｏ－单元中的中心Ｃ—Ｃ键主要以反式存在，而在极性大的溶剂如乙腈中则以邻交叉式为主．因此，开链冠醚末端取代的萘和蒽之间的距离随着溶剂极性的增大，能量转移效率却随之降低．表明能量转移可以用于探测以柔性配体键连接的给体－受体体系在不同极性溶剂中的构象变化特性．
An open chain crown ether (DSA) with a terminal substituted energy donor, naphthalene and its energy acceptor anthracene, was synthesized. Absorption spectra show that there is no interaction between the two chromophores in the ground state to selectively excite naphthalene and a decrease in the fluorescence intensity of naphthalene is observed accompanied by an increase in anthracene emission indicating a singlet-to- State energy transfer. The energy transfer efficiency is affected by the solvent polarity. It is believed that the central C-C bond in predominantly polar solvents, such as benzene-OCH2CH2O- units, predominantly exists in the trans form, whereas in polar solvents such as acetonitrile, the ortho-crossover predominates. Therefore, the distance between naphthalene and anthracene substituted by the terminal of open-chain crown ether decreases with the increase of solvent polarity and the energy transfer efficiency. It is shown that energy transfer can be used to detect the conformational change characteristics of donor-acceptor systems linked by flexible ligands in different polar solvents.