Accession Number : ADA320236
Title : Laser Probing of Cross Sections for Ionization of Excited States and Molecular Dissociation by Electron Impact.
Descriptive Note : Final rept. 1 Aug 92-31 Jul 96
Corporate Author : CALIFORNIA INST OF TECH PASADENA DIV OF CHEMISTRY AND CHEMICAL ENGINEERING
Personal Author(s) : McKoy, Vincent ; Srivastava, Santosh
PDF Url : ADA320236
Report Date : JUL 1996
Pagination or Media Count : 15
Abstract : Cross sections for electron-impact ionization of atoms and molecules and for electron-impact dissociation of molecules play an important role in determining the properties of electrical discharges, of the ionosphere and aurora, and of the plasmas that are widely used in microelectronics fabrication. The data base of these electron collision cross sections is very fragmentary or non-existent. This research has addressed these needs through the following accomplishments: Development, and application of a novel method for the measurement of accurate values of ionization cross sections of metal atoms. The discovery that the values of the ionization potential of C60 determined by the electron-impact and photoionization methods differ considerably indicating that low-lying metastable states are involved in the process. This may very well be the case for many other large molecules. Development of a time-of-flight, mass spectrometer of special design required for this effort.
Descriptors : *MOLECULAR STATES, *LASERS, *CROSS SECTIONS, *ELECTRIC DISCHARGES, *IONIZATION, *DISSOCIATION, DATA BASES, IONOSPHERE, METALS, PROBES, COMPUTATIONS, IMPACT, MICROPROCESSORS, COMPUTERS, MOLECULES, PROCESSING, PLASMAS(PHYSICS), EXCITATION, FABRICATION, PARALLEL PROCESSING, ATOMS, SEMICONDUCTORS, GASES, ELECTRONS, MICROELECTRONICS, LOW LEVEL, MASS SPECTROMETERS, AURORAE, PHOTOIONIZATION, PARALLEL ORIENTATION, ADAPTATION, METASTABLE STATE, PARTICLE COLLISIONS, IONIZATION POTENTIALS.
Subject Categories : Inorganic Chemistry
Electricity and Magnetism
Atomic and Molecular Physics and Spectroscopy
Distribution Statement : APPROVED FOR PUBLIC RELEASE