Analysis of X-ray photoelectron spectra of eight polymers by deMon density-functional calculations using the model oligomers

The X-ray photoelectron spectra of eight polymers [(CH2CH2)(n), (CH2CH2NH)(n), (CH2O)(n), (CH2CH2S)(n), (CH(2)CHX)(n), and (CH(2)CX(2))(n) (X = F, Cl)] were analyzed by the deMon density-functional method using the model oligomers. Calculated AIK a valence photoelectron spectra were obtained using Gaussian line shape functions of an approximate Line width (0.10I(k)), where I-k = I-k' - WD, I-k' is the vertical ionization potential of each MO, and WD is a shift to account for sample work function, polarization energy, and other effects. The theoretical spectra showed good agreement with the experimental spectra of the polymers between 0 and 40 eV. The core-electron binding energies (CEBEs) of C1s, N1s, O1s, F1s, S2p, and Cl2p of the model oligomers were calculated by unrestricted generalized transition-state models. The difference between the calculated and the experimental CEBEs reflects the trend in WDs of the polymers.