Photodissociation of Cr(CO)/sub 6/ in a molecular beam at 248 nm: Observation of primary and secondary photoproducts by mass spectrometry

Journal Article · Fri Sep 01 04:00:00 EDT 1989 · J. Chem. Phys.; (United States)

OSTI ID:6030683

Tyndall, G W; Jackson, R L

Photodissociation of Cr(CO)/sub 6/ induced by a KrF* excimer laser (248 nm) was examined under molecular beam conditions, using a quadrupole mass spectrometer with electron impact ionization (11--19 eV) to detect the products as their respective ions. The ions of all Cr(CO)/sub /ital x// products (/ital x/=0--5) were produced upon photodissociation of Cr(CO)/sub 6/ at laser fluences from 1 to 10 mJ cm/sup /minus/2/. The quantitative behavior of the Cr(CO)/sup +//sub /ital x// product ion yields vs laser fluence as well as statistical rate calculations indicate that Cr(CO)/sub 4/ is the major product formed upon single-photon dissociation of Cr(CO)/sub 6/ under collisionless conditions at 248 nm. The additional Cr(CO)/sup +//sub /ital x// (/ital x//lt/4) product ions observed at low fluences are formed primarily by electron-impact fragmentation of Cr(CO)/sub 4/ in the mass spectrometer ionizer. At laser fluences /approx gt/5 mJ cm/sup /minus/2/, secondary photodissociation of Cr(CO)/sub 4/ becomes important. Cr(CO)/sub 2/ is assigned as the major photoproduct formed via secondary photodissociation of Cr(CO)/sub 4/.

• Research Organization: IBM Almaden Research Center, San Jose, California 95120-6099 (US)
• OSTI ID: 6030683
• Journal Information: J. Chem. Phys.; (United States), Journal Name: J. Chem. Phys.; (United States) Vol. 91:5; ISSN JCPSA
• Country of Publication: United States
• Language: English

Related Subjects

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Molecular & Chemical Physics-- Beams & their Reactions
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
BEAMS
CARBONYLS
CHEMICAL REACTION YIELD
CHEMICAL REACTIONS
CHROMIUM COMPOUNDS
DECOMPOSITION
ELECTROMAGNETIC RADIATION
INFRARED SPECTRA
LASER RADIATION
MASS SPECTROSCOPY
MOLECULAR BEAMS
PHOTOCHEMICAL REACTIONS
PHOTOLYSIS
RADIATIONS
SPECTRA
SPECTROSCOPY
TRANSITION ELEMENT COMPOUNDS
YIELDS