Benchmark theoretical study of the ionization energies, electron affinities and singlet-triplet energy gaps of azulene, phenanthrene, pyrene, chrysene and perylene

► Electronic properties of aromatic hydrocarbons are computed at benchmark levels. ► Electron correlation has a very strong influence on the computed results. ► The role of structural relaxation and zero-point vibrations is highlighted. ► We approach chemical accuracy, using the principles of a focal point analysis.