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Absolute VUV optical absorption cross sections for ozone have been measured between 325 and 110 nm (3.0 - 11.3 eV) using a synchrotron radiation source. Vibrational fine structure is resolved in Rydberg bands and comparison of this with the limiting bands in the photoelectron spectrum confirms that the order (increasing ionization energy) of the three lowest ionization bands is . Near-threshold electron energy-loss spectra have also been recorded. In these, in addition to the known triplet states between 1 and 2 eV, a low-lying triplet state has been located around 3.4 eV and several others between 6 and 9 eV. Characterization of the valence states (both optically allowed and forbidden) are discussed in relation to the results of early theoretical computations which seem to give a good account of the ozone spectrum.

The high-resolution HeI 58.4 nm photoelectron spectrum of dichlorine monoxide, Cl O, has been recorded in the region 2 of the four lowest-energy ionic electronic states. Formation of the ion in its ground and excited electronic states is accompanied in each case by vibrational excitation. In particular, the vibrational structure of the first and second excited states of Cl O q is resolved. Analysis of the vibrational progressions associated with formation of the various ionic states has 2 been completed, allowing confirmation of the symmetry and bonding characteristics of the four highest-energy occupied molecular orbitals of Cl O.

Articles you may be interested inCross sections for the valence shell excitations of nitrous oxide studied by fast electron impact J. Chem. Phys. 132, 124301 (2010); 10.1063/1.3360311 2-methyl furan: An experimental study of the excited electronic levels by electron energy loss spectroscopy, vacuum ultraviolet photoabsorption, and photoelectron spectroscopy Electronic excitation spectrum of thiophene studied by symmetry-adapted cluster configuration interaction method Electronic excitation and oscillator strength of ethyl bromide by vacuum ultraviolet photoabsorption and electron energy loss spectroscopy Electronic excitation and oscillator strength of ethyl iodide by VUV photoabsorption and electron energy loss spectroscopy High resolution UV-VUV photon absorption spectra of methylamine and ethylamine have been recorded between 5.0-9.0 eV ͑250-140 nm͒ using synchrotron radiation. In methylamine, the energies of the absorption bands are confirmed as centered at 5.7, 7.2, and 8.7 eV, respectively. In ethylamine the band centers are 5.8, 7.0, and 7.9 eV, respectively; the last band is seen here for the first time. Most of the transitions exhibit rich fine structure dominated by vibrational progressions involving excitation of an amino wagging vibration. The absolute photoabsorption oscillator strengths have been measured by photon absorption over the 5-9 eV range and by dipolar electron energy loss spectroscopy from 5-14 eV ͑250-90 nm͒.

Dissociative electron attachment (DEA) in ozone has been explored for incident electron energies between 0 and 10 eV. Three resonant regions are observed centred around 1.4, 3.5 and 7.5 eV, respectively. Only the first of these had been reported prior to this work. For the 3.5 eV resonance, a single anionic state appears to be involved; decay is rapid, along the asymmetric stretch coordinate to and , each in its ground electronic state. Within the 7.5 eV resonance region, both two-body and three-body dissociations are active.