关键词: 1,3-二苯基-2-吡唑啉衍生物, 分子内电子转移, 溶致变色, 辐射衰减和非辐射衰减过程

Abstract: In this work, after the synthesis of a series of substituted diphenyl pyrazoline compounds, their solvatochromic behavior has been studied. The Bilot-Kawaski equation was used for calculating the difference of dipole moment of these compounds in their ground state and excited state respectively. Results indicated that the dipole moment can be changed dramatically when an electron-withdrawing group was attached with C-3 atom in the molecule. It demonstrated that the introduction of an electron-withdrawing group to the molecule may promote the intramolecular charge transfer process significantly. The E_T(30) value was used as an index for evaluating the polarity of solvents. It reveals that a series of photophysical properties of these compounds such as the fluorescence quantum yield, the fluorescence lifetime, the Stokes' shift and especially the radiation and radiationless decay rate constants may be correlated with E_T(30) value in linearity.

Key words: 1,3-diphenyl-2-pyrazoline derivatives, Solvatochromism, Radistion and radiationless decay rate constants, Intramolecular charge transfer