US EPA

7733598 

Journal Article 

Isotope effect on photoinduced isomerization of alkyl radicals trapped in 77 K solid alkanes 

Takada, T; Koizumi, H; Kagei, K; Ichikawa, T; Yoshida, H 

1997 

Yes 

Journal of Physical Chemistry B
ISSN: 1520-6106
EISSN: 1520-5207 

American Chemical Society 

101 

22 

4379-4382 

English 

10.1021/jp9640742 

WOS:A1997XB80100004 

Photoinduced isomerization of protiated and deuterated hexyl radicals in 77 K solid n-hexanes was examined. 2- and 3-hexyl-h13 radicals in n-hexane-h14 isomerize to 1-hexyl-h13 radicals with the irradiation of 254 nm light. This isomerization is suppressed by replacing the six hydrogen atoms of the methyl groups with deuterium atoms. The quantum yield for the isomerization of 2- and 3-hexyl-1,1,1,6,6,6-d6 n-hexane 1,1,1,6,6,6,-d6 and of 2- and 3-hexyl-d13 in n-hexane-d14 is less than 1/16 of that of 2- and 3-hexyl-h13 radicals in n-hexaneh14. Photoinduced isomerization of hexyl-h13 radicals in 77 K n-hexane-d14 was also examined. 2- and 3-hexyl-h13 radicals isomerize to 1-hexyl-h13 radical even in the solid. The isomerization may hence occur through an intramolecular reaction. The large isotope effect may arise in the course of either the isomerization in the excited state or the relaxation process of the excited primary radical.