4 K radiolysis of linear alkanes as studied by electron spin resonance spectroscopy: selective formation of terminal alkyl radicals in the primary process

Journal Article · Thu Nov 21 04:00:00 EST 1985 · J. Phys. Chem.; (United States)

DOI:https://doi.org/10.1021/j100270a032· OSTI ID:6051986

Iwasaki, M; Toriyama, K; Fukaya, M; Muto, H; Nunome, K

The primary mode of alkyl radical formation in irradiated crystals of linear alkanes from n-C6H14 to n-C25H52 has been studied by ESR at 4 K together with their secondary reactions upon warming up to 77 K. The terminal alkyl radical, which has not been detected by ESR until recently, is found to be selectively formed with a yield higher than that statistically expected regardless of the chain length. The result suggests that the primary event of the alkyl radical formation takes place at the chain ends. This is consistent with the recent finding of the position selectivity of deprotonation from the radical cations of linear alkanes to form terminal alkyl radicals. It is further found that the interchain radical site transfer reaction takes place at 45-65 K only in the even homologues higher than n-C10H22, resulting in the conversion of the terminal alkyl radical mainly to the penultimate radical, whereas it is prohibited in the odd homologues below 77 K. This is the cause of the even-odd alternation of the formation of the terminal alkyl radicals by irradiation at 77 K previously reported. The marked difference in the radical site transfer reaction rate in the even and odd homologues can be accounted for in terms of the difference in the alignment of the two neighboring chains in the triclinic for the even and the orthorhombic unit cell for the odd homologues. 40 references, 9 figures, 1 table.

• Research Organization: Government Industrial Research Institute, Nagoya, Japan
• OSTI ID: 6051986
• Journal Information: J. Phys. Chem.; (United States), Journal Name: J. Phys. Chem.; (United States) Vol. 89:24; ISSN JPCHA
• Country of Publication: United States
• Language: English

Related Subjects

38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEAR CHEMISTRY
400600* -- Radiation Chemistry
ALKANES
CHEMICAL RADIATION EFFECTS
CHEMICAL REACTIONS
CHEMISTRY
DATA
DECOMPOSITION
ELECTRON SPIN RESONANCE
EXPERIMENTAL DATA
HYDROCARBONS
INFORMATION
LOW TEMPERATURE
MAGNETIC RESONANCE
NUMERICAL DATA
ORGANIC COMPOUNDS
RADIATION CHEMISTRY
RADIATION EFFECTS
RADICALS
RADIOLYSIS
RESONANCE
ULTRALOW TEMPERATURE