Accession Number : ADA117247

Title :   Triply Differential Studies of Atomic and Molecular Photoionization Using Synchrotron Radiation.

Descriptive Note : Annual summary rept. 1 Oct 81-30 Sep 82,

Corporate Author : NATIONAL BUREAU OF STANDARDS WASHINGTON DC NATIONAL MEASUREMENT LAB

Personal Author(s) : Dehmer,J L ; Parr,Albert C ; Stockbauer,Roger

PDF Url : ADA117247

Report Date : 19 Jul 1982

Pagination or Media Count : 13

Abstract : Basic studies of the dynamics and spectroscopy of atomic and molecular photoionization have been carried out using three experimental probes. The first and most extensively used experimental approach involves triply differential (differential in incident wavelength, electron energy, and ejection angle) photoelectron measurements using synchrotron radiation. Measurements were conducted in the vacuum ultraviolet wavelength range up to hv approx. 35 eV on a large variety of atomic and molecular systems. Photoelectron branching ratios and angular distributions were obtained for all accessible states. A major emphasis of this work involved the initial exploration of novel effects of autoionization and shape resonances on alternative vibrational ionization channels. The second experimental approach entailed measuring the polarization of fluorescence following production of excited molecular ions by photoionization. This experiment allowed the direct measurement of the alignment of molecular ions produced by photoionization and, simultaneously, the branching ratios for degenerate photoelectron channels. The third experimental approach involved determining the photoelectron spectrum of an atomic cluster (Xe3) in a mixture of clusters formed in a supersonic expansion by the technique of photoion-photoelectron coincidence. (Author)

Descriptors :   *Photoionization, *Atoms, *Molecules, *Vacuum ultraviolet radiation, Synchrotrons, Ionization, Ions, Molecular ions, Fluorescence, Polarization, Clustering, Photoelectrons, Spectra, Spectroscopy, Resonance, Distribution

Subject Categories : Atomic and Molecular Physics and Spectroscopy

Distribution Statement : APPROVED FOR PUBLIC RELEASE