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Reports that rotationally resolved pulsed field ionization photoelectron (PFI-PE) spectra have been obtained for oxygen in the energy range of 12.05-18.15 eV. Relative vibrational band intensities for O[sup +][sub 2]; Spectral simulation and assignment of rotational branches.

Reports on the acquisition of rotationally resolved pulsed field ionization photoelectron spectra of oxygen covering the ionization transitions of O[sup +][sub 2](B [sup 2]Sigma[sup -][sub g], v[sup +]=0-7,N[sup +]...O[sub 2](X [sup 3]Sigma[sup -][sub g], v''=0,N''). Pulsed field ionization photoelectron measurements; Measurements of lifetimes for high-n Rydberg states.

Improves a newly developed experimental scheme for high resolution pulsed field ionization photoelectron (PFI-PE) studies of oxygen using the high resolution monochromatized multibunch undulator synchroton of the chemical dynamics beamline at the advanced light source. Advantage of the scheme for PFI-PE measurements to have no contamination by background electrons.

We have obtained rotationally resolved pulsed-field ionization photoelectron (PFI-PE) spectra for O[sub 2] in the energy range of 17.05-18.13 eV, covering the ionization transitions O[sub 2][sup +](A [sup 2]Π[sub u],v[sup +]=0-12,N[sup +])←O[sub 2](X [sup 3]Σ[sub g][sup -],v[sup ″]=0,N[sup ″]). Although these O[sub 2][sup +](A [sup 2]Π[sub u],v[sup +]) PFI-PE bands have significant overlaps with vibrational bands for O[sub 2][sup +](a [sup 4]Π[sub u]) and O[sub 2][sup +](X [sup 2]Π[sub g]), we have identified all the O[sub 2][sup +](A [sup 2]Π[sub u],v[sup +]=0-12) bands by simulation of spectra obtained using supersonically cooled O[sub 2] samples with rotational temperatures approx. 20 and 220 K. While these v[sup +]=0-12 PFI-PE bands represent the first rotationally resolved photoelectron data for O[sub 2][sup +](A [sup 2]Π[sub u]), the PFI-PE bands for O[sub 2][sup +](A [sup 2]Π[sub u],v[sup +]=9 and 10) are the first rotationally resolved spectroscopic data for these levels. The simulation also allows the determination of accurate ionization energies, vibrational constants, and rotational constants for O[sub 2][sup +](A [sup 2]Π[sub u],v[sup +]=0-12). The analysis of the PFI-PE spectra supports the conclusion of the previous emission study that the O[sub 2][sup +](A [sup 2]Π[sub u],v[sup +]=9 and 10) states are strongly perturbed by a nearby electronic state. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

We have obtained rotationally resolved pulsed field ionization-photoelectron (PFI-PE) spectra of O[sub 2] in the energy range of 16.0-18.0 eV, covering ionization transitions O[sub 2][sup +](a [sup 4]Π[sub u], v[sup +]=0-18,J[sup +])←O[sub 2](X [sup 3]Σ[sub g][sup .], v[sup ″]=0,N[sup ″]). Although these vibrational PFI-PE bands for O[sub 2][sup +](a [sup 4]Π[sub u], v[sup +]) have significant overlaps with those for O[sub 2][sup +](X [sup 2]Π[sub g]) and O[sub 2][sup +](A [sup 2]Π[sub u]), we have identified all O[sub 2][sup +](a [sup 4]Π[sub u], v[sup +]=0-18) bands by simulation of spectra obtained using supersonically cooled O[sub 2] samples with rotational temperatures approx. 20 and 220 K. While the v[sup +]=4-18PFI-PE bands represent the first rotationally resolved photoelectron data for O[sub 2][sup +](a [sup 4]Π[sub u]), the PFI-PE bands for O[sub 2][sup +](a [sup 4]Π[sub u], v[sup +]=10-18) are the first rotationally resolved spectroscopic data for these levels. The simulation also allows the determination of accurate ionization energies, vibrational constants, and rotational constants for O[sub 2][sup +](a [sup 2]Π[sub u], v[sup +]=0-18). The observed intensities of spin-orbit components for the majority of O[sub 2][sup +](a [sup 2]Π[sub u], v[sup +]) vibrational bands are in accordance with the forced spin-orbit/rotational autoionization mechanism. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]