Electron Spin Resonance Spectra of Monomeric and Dimeric Cations of Benzene

Abstract

Articles you may be interested inElectronic structure of the benzene dimer cation

The formation and reactions of aromatic dimer cations in a high pressure photoionization source

“…The bimolecular reaction rate is therefore at least a factor of 100 less than the termolecular rate. The only reaction of X that need be considered at high benzene concentration is reaction [6]. Figures 6 and 7 show the results of similar experiments carried out with toluene and mfluorotoluene.…”

“…Important reactions of the dimer cations in such The dimer cation of benzene (C,H,),+ has been Systems will be charge transfer to Species of lower studied in the gas phase (1-5) and has been ob-ionization potential and possibly exchange reacserved as an intermediate s~e c i e s in the radiolvsis tions the form of benzene (6). ~hermochkmical determinations yielded a binding energy for this "sandwich" shaped complex of 17 kcal mol-I, which is -6 kcal mol-' greater than that calculated for a purely electrostatic interaction (7).…”

Monomer- and polymer radicals of vinyl compounds: EPR and DFT studies of geometric and electronic structures in the adsorbed state

“…Silica gel support systems are widely used in studies of transition metal ions or complexes [25] and are successfully applied in controlled polymerization [26] and in studies of ionic radicals [27,28]. High resolution of the EPR spectra indicated a high degree of mobility for benzene cation radicals in an adsorbed layer.…”

ESR observation of redox processes on benzene-loaded NaPdY, NaPtY and NaCeY zeolites

“…The lines are separated by approximately 3.12 G (NaPdY zeolite), 3.03 G (NaPtY zeolite) and 2.96 G (NaCeY zeolite). This is not untypical for radical cations of benzene dimers which have been observed by ESR and ENDOR spectroscopy on different catalytic materials such as silica gel 12,13 and HY molecular sieve 13 after -and/or x-ray irradiation, with slightly smaller hyperfine splitting constants of 2.1, 12 2.38 13 and 2.29 G. 13 Corio and Shih also observed the dimer radical cation on oxygen-pretreated H Zeolon. It should be noted that the spectra are also compatible with an assignment to the biphenyl radical cation (Ph 2 C ) which was observed in trifluoroacetic acid, with coupling constants of 3.15 G for the ortho, 0.51 G for the meta and 6.3 G for the para protons, 15 and on H-ZSM-5 with similar values, although with a considerable anisotropy and unresolved meta couplings.…”