2，4，6－三苯基氧鎓盐分子内旋转受阻对其发光行为的影响

研究了４－位苯基取代基旋转受阻和旋转自由的２，４，６－三苯基氧盐的光物理性质。实验结果表明，当４－位苯基取代基旋转受阻时，氧盐化合物在激发态时引起的分子内极化程度比４－位取代基旋转自由的氧盐化合物大，即在激发态时旋转受阻氧盐化合物发生的分子内电荷转移能力较强；４－位取代基旋转自由的化合物的荧光量子产率随溶剂粘度的增大而有所增大，但旋转受阻化合物在相同的条件下则出现相反的结果。实验结果还表明，４－位取代苯基旋转受阻对化合物的荧光发射不利。

Influence of Hindered Molecular Structure on Luminesence Behavior of 2,4,6-Triphenyl Pyrylium Salt

The photophysical properties of 2,4,6-triphenyl pyrylium salts(compounds 1 and 2) were investigated.It was found that the intramolecular charge transfer in excited state of compound 2,in which the rotation of 4-phenyl is hindered,is stronger than that of compound 1,in which the rotation of 4-phenyl is free.The quantum yields of compound 1 increased with increasing viscosity of solvents,while the quantum yields of compound 2 decreased under the same condition.It was also shown that the hindered rotation of 4-phenyl in the molecule of 2,4,6-triphenyl pyrylium salt is unfavorable to its fluorescence emission.