Photoelectron spectroscopy of negative ions

Thesis/Dissertation · Thu Dec 31 23:00:00 EST 1992

OSTI ID:6908709

Gilles, M K

Ultraviolet photoelectron spectroscopy of negative ions was used to probe the anionic and neutral states of the halogen monoxides, halogen dioxides, halocarbenes, and fluorovinylidene species. Ions, created in a flowing afterglow source, were mass selected and photodetached by continuous monochromatic laser radiation, and the kinetic energy of the photodetached electrons were determined. The photoelectron spectra provide electronic and vibrational structure. Photoelectron spectra of the halogen monoxides yielded adiabatic electron affinities, neutral and anion frequencies, and spin-orbit splittings. Franck-Condon analyses provided the change in bond length between the neutral and anion species. Neutral heats of formation and dissociation energies were combined with electron affinities to determine anion heats of formation and dissociation energies. Adiabatic electron affinities, neutral vibrational frequencies and anion vibrational frequencies were determined from photoelectron spectra of OClO[sup [minus]] and OIO[sup [minus]]. Photoelectron spectra of halocarbenes taken at the magic angle were used to determine electron affinities, anion state geometries, and anion and single state C-X vibrational frequencies. Photoelectron spectra taken with the electric vector horizontal and vertical to the direction of electron detection were used to isolate the halocarbene triplet states. The spectra of the isolated triplet states were combined with ab initio geometries to estimate the halocarbene singlet-triple splittings. Photoelectron spectra of monofluorovinylidene and difluorovinylidene negative ions yielded information of the vibrational and electronic structure of the neutral singlet and triplet states. The isomerization coordinate for the monofluorovinylidene [yields] fluoroacetylene reaction was investigated by taking a photoelectron spectrum of the negative ion, HFC [double bond] C[sup [minus]].

• Research Organization: Colorado Univ., Boulder, CO (United States)
• OSTI ID: 6908709
• Country of Publication: United States
• Language: English

Related Subjects

664200* -- Spectra of Atoms & Molecules & their Interactions with Photons-- (1992-)
74 ATOMIC AND MOLECULAR PHYSICS
ANIONS
CHALCOGENIDES
CHARGED PARTICLES
ELECTRON SPECTROSCOPY
ELECTRONIC STRUCTURE
ENERGY LEVELS
EXCITED STATES
FRANCK-CONDON PRINCIPLE
HALOGEN COMPOUNDS
IONS
OXIDES
OXYGEN COMPOUNDS
PHOTOELECTRON SPECTROSCOPY
SPECTROSCOPY
VIBRATIONAL STATES