The Pentafluorophenyl Cation: A Superelectrophile and Diradical.

ABSTRACT: We report the first direct observation of the pentafluorophenyl cation in the gas phase via vacuum ultraviolet (VUV) photoionization (PI) of the thermally generated pentafluorophenyl radical. The reactive intermediates and stable reaction products were characterized utilizing photoelectron photoion coincidence (PEPICO) spectroscopy with synchrotron radiation. Electron removal from the pentafluorophenyl radical yields the cation with an adiabatic ionization energy (AIE) of 9.84 ± 0.02 eV. Threshold photoelectron spectra combined with high-level ab-initio calculations show that the cation is described as a π⁵σ¹ diradical with an open-shell singlet (¹A₂) ground state, while the triplet (³A₂) state lies only 1.5 ± 0.4 kcal mol

SUBMITTER: Mendez-Vega E 

PROVIDER: S-EPMC12455445 | biostudies-literature | 2025 Sep

REPOSITORIES: biostudies-literature