Radiolysis of cyclooctane with [gamma]-rays and helium ions

Journal Article · Thu Aug 18 00:00:00 EDT 1994 · Journal of Physical Chemistry; (United States)

DOI:https://doi.org/10.1021/j100084a016· OSTI ID:6970327

Wojnarovits, L; LaVerne, J A ^[1]

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1. Univ. of Notre Dame, IN (United States)

Iodine scavenging techniques have been used to examine the role of the cyclooctyl radical in the radiolysis of cyclooctane with [gamma]-rays and with 5-20-MeV helium ions. In [gamma]-radiolysis about 70% of the total yield of 6.6 cyclooctyl radicals/100 eV are scavenged with 10[sup [minus]4] M iodine, which agrees well with other studies on cycloalkanes that show most of the radicals produced in these systems react in the bulk medium at times longer than 1 [nu]s. However, it is found that 2.5 radicals/100 eV (38%) are produced by H atom precursors as compared to a value of 1.5 cyclohexyl radicals/100 eV (25%) in cyclohexane. With 10-MeV helium ions (average LET of 106 eV/nm), only 8% of the cyclooctyl radicals survive longer than a few microseconds due to the increased initial radical concentration in the helium ion track. The yield of the cross-bridged product bicyclo[3.3.0]octane (pentalane) was found to be independent of iodine concentration up to 0.03 M with both types of radiation. However, the pentalane yield found with 10-MeV helium ions was only one-third of that found in [gamma]-radiolysis. The most likely reason for this result is the decreased yield of singlet-state formation due to the enhanced probability of cross combination reactions of electron-cation pairs in the high-density region of the helium ion track. 29 refs., 4 figs., 1 tab.

• OSTI ID: 6970327
• Journal Information: Journal of Physical Chemistry; (United States), Journal Name: Journal of Physical Chemistry; (United States) Vol. 98:33; ISSN JPCHAX; ISSN 0022-3654
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEAR CHEMISTRY
400102 -- Chemical & Spectral Procedures
400201 -- Chemical & Physicochemical Properties
400600* -- Radiation Chemistry
ALKANES
CHARGED PARTICLES
CHEMICAL RADIATION EFFECTS
CHEMICAL REACTIONS
CHROMATOGRAPHY
CYCLOALKANES
CYCLOHEXANE
DECOMPOSITION
ELECTROMAGNETIC RADIATION
ELEMENTS
GAMMA RADIATION
GAS CHROMATOGRAPHY
HALOGENS
HELIUM IONS
HYDROCARBONS
IODINE
IONIZING RADIATIONS
IONS
MASS SPECTROSCOPY
NONMETALS
ORGANIC COMPOUNDS
RADIATION EFFECTS
RADIATIONS
RADICALS
RADIOLYSIS
SCAVENGING
SEPARATION PROCESSES
SPECTROSCOPY