Laser photolysis of UF/sub 6/: Reactions of the transient UF/sub 5/ molecules

Journal Article · Mon Dec 01 04:00:00 EST 1980 · J. Chem. Phys.; (United States)

OSTI ID:6789501

Kim, K C; Reisfeld, M; Seitz, D

Laser photolysis of UF/sub 6/ at 248 nm produces vibrationally and translationally excited UF/sub 5/ and F. At very low pressures (<0.1 Torr) in a long path-length reaction cell collisional stabilization is inefficient, which tends to increase the lifetime of the transient UF/sub 5/ molecule. From the kinetic analysis of the UF/sub 5/ absorption--decay curve and the UF/sub 6/ depletion measurements the following dimerization and fluorine atom recombination rate constants were determined for 298 K. RRKM calculations were performed for the formed UF/sub 6/ molecule which indicated the unimolecular decomposition rate constant to be approx.1 x 10/sup 6/ s/sup -1/. The calculated results indicate that in the primary photolysis about 2/5 of the excess energy above the threshold energy was partitioned into the relative translational energy which is in good agreement with the experimental kinetic analysis and also with the available molecular beam data. The translational energy release from the decomposition of the chemically activated UF/sub 6/ molecule is small and two energetically different UF/sub 5/ species are suggested.

• Research Organization: University of California, Los Alamos Scientific Laboratory, Los Alamos, New Mexico 87545
• OSTI ID: 6789501
• Journal Information: J. Chem. Phys.; (United States), Journal Name: J. Chem. Phys.; (United States) Vol. 73:11; ISSN JCPSA
• Country of Publication: United States
• Language: English

Related Subjects

640302* -- Atomic
Molecular &amp; Chemical Physics-- Atomic &amp; Molecular Properties &amp; Theory
74 ATOMIC AND MOLECULAR PHYSICS
ACTINIDE COMPOUNDS
CHEMICAL REACTION KINETICS
CHEMICAL REACTIONS
DECOMPOSITION
ELECTROMAGNETIC RADIATION
FLUORIDES
FLUORINE COMPOUNDS
HALIDES
HALOGEN COMPOUNDS
KINETICS
LASER RADIATION
PHOTOCHEMICAL REACTIONS
PHOTOLYSIS
RADIATIONS
REACTION KINETICS
URANIUM COMPOUNDS
URANIUM FLUORIDES
URANIUM HEXAFLUORIDE
URANIUM PENTAFLUORIDE