title: Photoionization studies on various quinones by an infrared laser desorption/tunable VUV photoionization TOF mass spectrometry.
abstract: Photoionization and dissociative photoionization characters of six quinones, including 1,2-naphthoquinone (1,2-NQ), 1,4-naphthoquinone (1,4-NQ), 9,10-phenanthroquinone (PQ), 9,10-anthraquinone (AQ), benz[a]- anthracene-7,12-dione (BAD) and 1,2-acenaphthylenedione (AND) have been studied with an infrared laser desorption/tunable synchrotron vacuum ultraviolet (VUV) photoionization mass spectrometry (IR LD/VUV PIMS) technique. Mass spectra of these compounds are obtained at different VUV photon energies. Consecutive losses of two carbon monoxide (CO) groups are found to be the main fragmentation pathways for all the quinones. Detailed dissociation processes are discussed with the help of ab initio B3LYP calculations. Ionization energies (IEs) of these quinones and appearance energies (AEs) of major fragments are obtained by measuring the photoionization efficiency (PIE) spectra. The experimental results are in good agreement with the theoretical data.
authors.affiliation: National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, Anhui 230029, PR China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Pan
authors.forename: Lidong
authors.initials: L
authors.lastname: Zhang
authors.forename: Taichang
authors.initials: T
authors.lastname: Zhang
authors.forename: Huijun
authors.initials: H
authors.lastname: Guo
authors.forename: Xin
authors.initials: X
authors.lastname: Hong
authors.forename: Fei
authors.initials: F
authors.lastname: Qi