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The authors have obtained rotationally resolved vacuum ultraviolet pulsed field ionization-photoelectron (vuv-PFI-PE) spectrum of HD in the photon energy range of 15.29–18.11 eV, covering the ionization transitions HD+(X 2Σg+,v+=0–21,N+)←HD(X 1Σg+,v″=0,J″). The assignment of rotational transitions resolved in the vuv-PFI-PE vibrational bands for HD+(X 2Σg+,v+=0–20) and their simulation using the Buckingham-Orr-Sichel (BOS) model are presented. Rotational branches corresponding to the ΔN=N+-J″=0, ±1, ±2, ±3, and ±4 transitions are observed in the vuv-PFI-PE spectrum of HD. The BOS simulation shows that the perturbation of vuv-PFI-PE rotational line intensities due to near resonance autoionization is very minor at v+>=5 and decreases as v+ is increased. Thus, the rotationally resolved PFI-PE bands for HD+(v+>=5) presented here provide reliable estimates of state-to-state cross sections for direct photoionization of HD, while the rotationally resolved PFI-PE bands for HD+(v+<5) are useful data for fundamental understanding of the near resonance autoionizing mechanism. On the basis of the rovibrational assignment of the vuv-PFI-PE bands, the ionization energies for the formation of HD+(X 2Σg+,v+=0–20,N+) from HD(X 1Σg+,v″=0,J″) and the vibrational constants (ωe, ωeχe, ωeye, and ωeze), the rotational constants (Be and αe), the vibrational energy spacings, and the dissociation energy for HD+(X 2Σg+) are determined. As expected, these values are found to be in excellent agreement with high level theoretical predictions. [ABSTRACT FROM AUTHOR]

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.

Examines the pulsed field ionization photoelectron spectrum (PFI-PE) of oxygen gas. Observation on the rotational branches; Estimation of the rotational linewidths; Determination of the predissociation lifetimes; Calculation of equilibrium bond distances; Measurement of nominal lifetimes for Rydberg states.

Examines the collision-induced dissociation (CID) reaction of chloro compounds. Measurement of the absolute total cross sections produced by the CID reaction in the center-of-mass collision energy; Validity of the energy randomization of chloro compounds; Promotion of couplings or energy flow among the vibrational modes.

Presents a theoretical study of the vacuum ultraviolet pulsed field ionization photoelectron band for carbonyl sulphide. Correlation between the experimental and theoretical Renner-Teller calculations of the vibronic states; Factors attributing the symmetry of geometry-dependent electronic transition dipole operator components.

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]