Theoretical valence photoelectron and UV-visible absorption spectra of four stable conductive molecules obtained by MO calculations

Theoretical valence photoelectron and UV-visible absorption spectra of four stable conductive molecules (N, N'-diphenyl-1,4-phenylenediamine (DPPD), p -quaterphenyl (PQP), 2, 3, 7, 8, 12, 13, 17, 18-octaethyl-21H, 23H-porphyri n (OEP), and 29H, 31H-phthalocyanine (PC)) have been obtained by semiempiri cal HAM/3 and ZINDO MO calculations, respectively. The Al K alpha photoelec tron spectra were simulated using Gaussian lineshape functions of an approx imate linewidth 0.10 E-k (E-k = E-k' - WD), where E-k' is the vertical ioni zation potential (VIP) of each MO and WD is a shift to account for sample w ork function and other energy effects, as stated in previous studies. The t heoretical valence spectra of the four conductive compounds are in good acc ordance with the observed ones. The theoretical UV-visible absorption curve s of DPPD, PQP, OEP, and PC were obtained after AM1 calculations with COSMO option to reflect solvent effects. The absorption curves as simulated with Gaussian lineshape functions of a constant linewidth of 0.003 eV. Correspo nd well to the observed spectra. For PC, the simulated spectrum which consi sts of 0.5 inner protonation (IP) and 0.5 outer protonation (OP) types for PC-ring shows much better agreement with the experimental spectrum in H2SO4 than the spectrum of either TP or OP type alone.