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The UV-Vis absorption and fluorescence spectra of alpha-carboline(AC)and carbazole(CZ)in different solvents,n-hexane and acetonitrile,have been simulated by using Franck-Condon simulation including inhomogeneous broadening of solvent effects.Displaced harmonic oscillator and scaling factors on the force constant have been applied in the simulation.The equilibrium geometries have been calculated in gas phase and with polarizable continuum model(PCM)in solvent n-hexane and acetonitrile respectively.The DFT method is used to calculate the equilibrium geometries of the ground state S0 for AC and CZ,and the TDDFT method is used to calculate the equilibrium geometries of the first two singlet excited states S1 and S2.The forces on the solute by solvent can change the restoring force of the atoms in the solute molecule,and we can treat it as constant scaling factors on the force constant.The simulated spectra by using the geometries in gas phase with scaling factors is much better than that without scaling factors,and the spectra by using the geometries in solvent with scaling factors can match the experiment data almost completely.