Accession Number : AD0693347

Title :   DISSOCIATIVE ATTACHMENT OF ELECTRONS IN AMMONIA AND AMMONIA-d3,

Corporate Author : LOCKHEED MISSILES AND SPACE CO PALO ALTO CALIF LOCKHEED RESEARCH LAB

Personal Author(s) : Sharp,T. E. ; Dowell,J. T.

Report Date : 08 JUL 1968

Pagination or Media Count : 12

Abstract : Cross sections for total negative ions and amino negative ions have been measured as a function of energy for dissociative attachment of electrons in the gases NH3 and ND3. Two peaks are observed, at 5.65 and 10.5 eV. Both peaks contain H(-)(D(-)) and NH2(-)(ND2(-). Small direct isotope effects were found, in negative ion production, except for H(-)/D(-) formation at 5.65 eV where the isotope effect was 1.0. The peak at 5.65 eV leads to products in their ground states. The corresponding potential-energy-vs-internuclear-distance (H-NH2) curve for NH3(-) may contain a hump or may merely have a shallow slope in the Franck-Condon region. The peak at 10.5 eV arises from a repulsive state of NH3(-), and the amino fragment is formed in an excited state. Empirical trends in the isoelectronic series methane, ammonia, and water are identified. (Author)

Descriptors :   (*AMMONIA, *ELECTRON IRRADIATION), (*DISSOCIATION, AMMONIA), DEUTERIUM COMPOUNDS, PLASMAS(PHYSICS), GAS IONIZATION, ELECTRON TRANSITIONS, MOLECULAR ENERGY LEVELS

Subject Categories : Atomic and Molecular Physics and Spectroscopy

Distribution Statement : APPROVED FOR PUBLIC RELEASE