A SIMULTANEOUS STUDY OF PHOTOELECTRON-SPECTRA, UV SPECTRA AND ELECTRON-AFFINITIES OF ADENINE AND GUANINE WITH THE SEMIEMPIRICAL HAM/3 METHOD

Ionization energies, excitation energies and electron affinities (EAs) of the title molecules were calculated with HAM/3. The photoelectron spectra (PES) and UV spectra of the molecules were interpreted with the aid of the calculated ionization and excitation energies respectively. The accuracy of the calculated EAs was estimated on the basis of the information obtained from the PES and UV spectra. It can be shown that the calculations give reasonable agreement between theory and experiment in all three cases.