摘要
根据Ｆｒａｎｋ－Ｃｏｎｄｏｎ原理，应用自编的分子轨道法（ＰＰＰ－ＣＩ）程序计算了３４种芳烃化合物基态和第一激发单重态在π电荷分布、偶极矩、键级以及各分子轨道的能极分布的变化。计算的分子吸收光谱波长与实验值较好地一致，并发现计算得到的荧光辐射能ΔＥｆＬ与荧光光谱波数ｆＬ存在如下关系：ｆＬ＝７．１９３０ΔＥｆＬ＋２３．３３３４（ｋｃｍ－１）ｒ＝０．９８６８并对激发态结构进行了讨论。
The fluorescence and the difference between ground state and the first excited singlet states in π electron densities,dipole moments,bond orders and energy levels distribution of 34 aromatic compounds have been studied by means of the PPP-CI method on microcomputer.The calculated wavelength of absorption are good consistency with experimental ones.it is found that there are good correlated relationship between the wavenumber of fluorescence maxima UfL and the calculated fluorescence emission energy ΔEfl.Ufl=7.1930 ΔEfl+23.3334 (kcm-1)r=0.9869the structure of excited state has been discussced.
关键词
量子化学
荧光光谱
芳香族烃
quantum-chemistry
fluorescence spectra
absorption spectr excited state
