首次系列报道了9-H咔唑及其系列N-取代衍生物的气相HeI紫外光电子能谱,借助于Gauss-94采用RHF/3-21G基组对它们的几何构型进行优化,并用RHF/6-31G基组计算分子轨道及能级,计算的分子轨道特征和能量很好地反映了各谱带的特点和分子间电离能的变化规律.依计算结果,以及同系列分子间谱带及相应电离能的相互比较,对每个分子的UPS谱带给予指认,讨论了N-烷基化对π分子轨道的选择性去稳定化作用,并讨论了分子之间电离能的变化规律,得到一系列有益的结论. The first series reported the gas-phase HeI UV-Vis spectra of 9-H carbazole and its series of N-substituted derivatives, optimized their geometries with the help of Gauss-94 using the RHF / 3-21G basis set, The 6-31G basis set calculates the molecular orbital and energy level, and the calculated molecular orbital characteristics and energy well reflect the characteristics of each band and the variation law of the ionization energy between molecules. According to the calculation results, The corresponding ionization energies are compared with each other to identify the UPS bands. The selective destabilization of π-molecular orbitals by N-alkylation is discussed. The variation of the ionization energy between molecules is discussed. A series of useful conclusions.