Excimer laser photolysis of V(CO)/sub 6/: time-resolved infrared studies of gas-phase V(CO)/sub x/ (x = 5-2)

Journal Article · Wed Oct 28 04:00:00 EST 1987 · J. Am. Chem. Soc.; (United States)

DOI:https://doi.org/10.1021/ja00256a015· OSTI ID:5522052

Ishikawa, Y; Hackett, P A; Rayner, D M

The photolysis of gas-phase vanadium hexacarbonyl V(CO)/sub 6/, has been studied at excimer laser wavelengths (351, 308, 248, and 193 nm) by observing the coordinatively unsaturated transient products, V(CO)/sub x/ (x = 5-3 and possibly 2), via time-resolved infrared kinetic absorption spectroscopy. The dependence of the initial fragment distribution on photolysis wavelength is consistent with the model of sequential CO elimination established by similar studies on Fe(CO)/sub 5/, Cr(CO)/sub 6/, and Co(CO)/sub 3/NO. The high reactivity of unsaturated metal carbonyl species with saturated carbonyls to form binuclear complexes is again observed, with rate constants for the reaction of V(CO)/sub 3/ and V(CO)/sub 4/ with V(CO)/sub 6/ found to be of the order 3 x 10/sup -10/ cm/sup 3/ molecule/sup -1/ s/sup -1/. Infrared assignments for V(CO)/sub x/ are supported by kinetic measurements in the presence of added CO. Rate constants for the reaction of CO with V(CO)/sub 3/, V(CO)/sub 4/, and V(CO)/sub 5/ are found as (0.4 +/- 0.1) x 10/sup -10/, (0.5 +/- 0.1) x 10/sup -10/, and (0.5 +/- 0.1) x 10/sup -10/ cm/sup 3/ molecule/sup -1/ s/sup -1/, respectively, leading to the expectation that ground-state V(CO)/sub 3-5/ share the doublet character of V(CO)/sub 6/. The infrared assignments are in disagreement with infrared absorption and some ESR studies of V(CO)/sub x/ fragments in low-temperature matrices.

• Research Organization: National Research Council, Ottawa, Ontario
• OSTI ID: 5522052
• Journal Information: J. Am. Chem. Soc.; (United States), Journal Name: J. Am. Chem. Soc.; (United States) Vol. 109:22; ISSN JACSA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400500* -- Photochemistry
ABSORPTION SPECTROSCOPY
CARBONYLS
CHEMICAL REACTION KINETICS
CHEMICAL REACTIONS
COMPLEXES
DATA
DECOMPOSITION
ENERGY LEVELS
EXCIMER LASERS
EXPERIMENTAL DATA
FLUIDS
GAS LASERS
GASES
GROUND STATES
INFORMATION
INFRARED SPECTRA
KINETICS
LASERS
NUMERICAL DATA
PHOTOCHEMICAL REACTIONS
PHOTOLYSIS
REACTION KINETICS
SPECTRA
SPECTROSCOPY
TRANSITION ELEMENT COMPLEXES
VANADIUM COMPLEXES