Accession Number : ADA098265
Title : Properties of the Excited States of Molecular Ions.
Descriptive Note : Final rept. 1 Oct 77-15 Sep 80,
Corporate Author : SRI INTERNATIONAL MENLO PARK CA MOLECULAR PHYSICS LAB
Personal Author(s) : Cosby,Philip C ; Moseley,John T ; Peterson,James R ; Helm,H P ; Lee,L C
Report Date : 13 Apr 1981
Pagination or Media Count : 127
Abstract : The techniques of photodissociation-spectroscopy and photofragment spectroscopy were developed and applied to characterize the excited states of a number of important molecular ions that occur in both natural and laboratory discharges and plasmas. Dissociative excited states in O2(+) and NO(+) were identified, together with their predissociation mechanisms, using photofragment spectroscopy techniques. This work yielded an order of magnitude improvement in resolution over conventional spectroscopic techniques, measurements of predissociation lifetimes, and several new observations of molecular dynamics and properties. In NO(+) a complicated band system was found to consist of transitions to predissociated levels of the previously unobserved 2 3 Pi state. These studies will have a major impact on current knowledge of NO(+) excited states. The structure of the OONO(-) isomer of NO3(-) was confirmed, and the probable mechanism for its stabilization in atmospheric reactions was identified as due to clustering with H2O, which preserves its structure and prevents conversion to NO3(-). The possibility that previous observations of CO3(-) photodissociation in a drift tube can be attributed to excited ions was investigated. The results showed that the drift tube CO3(-) ions are in the ground state, but were not able to resolve the discrepancy in the CO3(-) bond dissociation energy.
Descriptors : *PHOTODISSOCIATION , *PLASMAS(PHYSICS) , *GAS DISCHARGES , *MOLECULAR IONS , REACTION KINETICS , CHEMICAL DISSOCIATION , MOLECULAR STATES , EXCITATION , EMISSION SPECTRA , LASER BEAMS , OXYGEN , RADIATION ABSORPTION , MASS SPECTROMETERS , ABSORPTION SPECTRA , NITROGEN OXIDES , MOLECULAR PROPERTIES , FRAGMENTS , DRIFT TUBE MASS SPECTROSCOPY
Subject Categories : Atomic and Molecular Physics and Spectroscopy
Nuclear Physics & Elementary Particle Physics
Plasma Physics and Magnetohydrodynamics
Distribution Statement : APPROVED FOR PUBLIC RELEASE