ZEKE spectroscopy of aniline–X (X=Ar, Kr, N2 and CO) van der Waals complex cations Original Research Article

We have measured zero kinetic energy (ZEKE) photoelectron spectra of van der Waals (vdW) complexes of aniline with Ar, Kr, N2 and CO in the region of the first ionization limit of these complexes. The measurements on the aniline–Kr complex have allowed the frequencies of all three modes of the cation of this species and the adiabatic ionization energy (AIE) of this complex to be determined. These data have allowed the determination of the by+2 vibrational level in aniline–Ar cation for the first time. The vdW structure of the S1–S0 band of neutral aniline–Kr was also measured. We have reexamined the S1–S0 band of neutral aniline–N2 and have made tentative assignments of the vdW structure. These data have allowed structure in the ZEKE spectrum of aniline–N2 to be provisionally identified as a progression in the bending mode, bx, of the cation and the AIE of the complex to be determined. A broad unresolved signal was observed in the ZEKE spectrum of the aniline–CO complex. A lower limit for the AIE of this complex was determined.