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We have demonstrated the two-color vacuum ultraviolet (VUV)-infrared (IR) photoinduced Rydberg ionization (PIRI) experiment. Trichloroethene (ClCH==CCl[sub 2]) and trans-2-butene (trans-CH[sub 3]CH==CHCH[sub 3]) were prepared in Rydberg states in the range of effective principal quantum number n[sup *]≈7–93 by VUV excitation prior to IR-induced autoionization. The observed VUV-IR-PIRI spectra are found to be independent of n[sup *], suggesting that the electron Rydberg orbital is conserved, i.e., the Rydberg electron is behaving as a spectator during the excitation process. The observed IR active C–H stretching vibrational frequencies ν[sub 12][sup +]=3072±5 cm[sup -1] for ClCH==CCl[sub 2][sup +] and ν[sub 23][sup +]=2908±3 cm[sup -1], ν[sub 25][sup +]=2990±10 cm[sup -1] and ν[sub 30][sup +]=3022±10 cm[sup -1] for trans-CH[sub 3]CH==CHCH[sub 3][sup +] are compared with predictions based on ab initio quantum-chemical procedures and density functional calculations. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Discusses an experimental and theoretical study of the spin-orbit interaction for carbon dioxide and oxygen. Rotationally resolved pulsed field ionization photoelectron (PFI-PE); Angular momentum coupling factor for the photoionization of the present carbon dioxide system.

Studies rotationally resolved pulsed filed ionization photoelectron (PFI-PE) spectra of NO at a specific energy range covering ionization transitions. PFI-PE bands for NO that represent the first rotationally resolved spectroscopic data for these states; Increase in inelastic cross sections for collisions.

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.

The vacuum ultraviolet pulsed field ionization-photoelectron (PFI-PE) spectra for CO[sub 2] have been measured in the energy range of 13.6-14.7 eV, revealing complex vibronic structures for the ground CO[sub 2][sup +](X [sup 2]Π[sub g]) state. Many vibronic bands for CO[sub 2][sup +](X [sup 2]Π[sub g]), which were not resolved in previous photoelectron studies, are identified in the present measurement based on comparison with available optical data and theoretical predictions. As observed in the HeI photoelectron spectrum of CO[sub 2], the PFI-PE spectrum is dominated by the symmetry allowed ν[sub 1][sup +] (symmetric stretch) vibrational progression for CO[sub 2][sup +](X [sup 2]Π[sub g]). However, PFI-PE vibronic bands due to excitation of the symmetry disallowed ν[sub 2][sup +] (bending) and ν[sub 3][sup +] (asymmetric stretch) modes with both odd quanta, together with the symmetry allowed even quanta excitations, are clearly discernible. The simulation of rotational contours resolved in PFI-PE vibronic bands associated with excitation to the (ν[sub 1][sup +]=0-1, ν[sub 2][sup +]=0-2, ν[sub 3][sup +]=0) vibrational levels has yielded accurate ionization energies for the formation of these vibronic states from CO[sub 2](X [sup 1]Σ[sub g][sup +]). © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

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]

Abstract: The comparison of rotationally resolved infrared–vacuum ultraviolet–pulsed field ionization–photoelectron (IR–VUV–PFI–PE) depletion and IR–VUV–photoion measurements of C2H4 has illustrated the difference of these two methods and the rotational nature of the IR–VUV–PFI–PE depletion method. The IR–VUV–photoion spectra of trans-2-butene in the region 2910–3000cm−1 observed at different delays between the IR and VUV lasers are also presented to show that the IR–VUV–PI method is potentially useful for the study of intramolecular vibrational redistributions (IVRs). For short IVR lifetimes of vibrationally excited polyatomic neutrals, the IR–VUV–PFI–PE depletion method can serve as an alternative of the IR–VUV–PI scheme for rotationally resolved IR spectroscopy measurements. [Copyright &y& Elsevier]