Disentangling the complex line profiles in the Cl 2p photoelectron spectra of Cl2

High-resolution Cl (2p) photoelectron spectra of Cl2 are reported and their complex structure is analyzed in detail, taking into account molecular field (MF), spin-orbit (SO) and parity splitting. High-level ab initio calculations were performed. ΔMF = 86 ± 7 meV, ΔSO = 1630 ± 8 meV and the lifetime line widths Γ(2Π12)=92±5, Γ(2Σ12+)=79±11, Γ(2Π32)=105±12meV were derived from experiment.