Core ionization of nitrosobenzene-dimer compounds: phenazon-di-N-oxide
Abstract The C 1s, N 1s and O 1s XPS spectra of soli d phenazon-di-N-oxide (PADNO) are presented in order to further elucidate the effects of intermolecular interactions in molecular solids on the dynamics of the core-ionization process. PADNO can be considered a model compound for an intramolecular cis nitrosobenzene dimer. The observed strong N 1s and O 1s shake-up intensity attenuations in going from the nitrosobenzene monomer to PADNO are discussed in detail based on the results of CNDO/S CI equivalent core calculations. The theoretical core-hole spectral functions are in excellent agreement with experiment. It is shown that the calculated shake-up intensities are strongly on electron correlation.
Use of the CNDO Method in Spectroscopy. III. Monosubstituted Benzenes and Pyridines
The modified CNDO method previously reported has been applied to the calculation of a series of monosubstituted benzenes and pyridines, namely, aniline, anilinium ion, benzonitrile, nitrosobenzene, phenol, phenoxide ion, toluene, pyridinium ion, pyridine‐N‐oxide, 1‐hydroxy‐pyridinium ion, the aminopyridines, and the cyanopyridines. The calculated values of the transition energies and corresponding oscillator strengths are in good agreement with available experimental data on the electronic spectra of these compounds. An analysis of the lower‐energy excited states by means of the calculated results suggests that there is an astonishingly small amount of charge‐transfer character associated with the observed ultraviolet bands. The calculations indicate that the changes in charge densities in going from the ground state to the lowest energy π → π* excited state can be related to the Hammett σ's for the substituents.
Interaction of perpendicular π-electron systems—II Amino-biphenyls
Abstract The near ultraviolet absorption spectra of a series of ortho -ammonio substituted biphenyls are determined and interpreted as indicating some significant resonance interaction between perpendicular phenyl rings in the most sterically hindered biphenyls.