The Ranges of Interactions in the Radiolysis of Solid Hydrocarbon Mixtures

Self Cite

γ-Irradiated glasses of methyltetrahydrofuran at 77 °K exhibit photoconductivity on illumination with visible light. A variety of kinetic effects are observed as the wavelength of the exciting light is changed from blue to the near infrared. It is suggested that, due to the coulombic field of the positive ions in the glass, some electrons can be released by red light while others can be released only by blue light. A thermally unstable red sensitive center can also be formed in the glass during illumination with blue light. This unstable center could be a dielectron.

supporting

confidence: 62%

Photoconductivity of γ-irradiated methyltetrahydrofuran glass at 77 °K

Baverstock¹,

Dyne²

1970

Self Cite

“…[3a] is radicals are produced and therefore that probably a "hot" hydrogen atom (8). [7] and [8] do occur to some extent.…”

Section: Results a N D Discussionmentioning

confidence: 99%

Secondary reactions in the γ-radiolysis of hydrocarbons with electron scavengers

Sagert¹,

Blair²

1967

Secondary reactions in the liquid phase radiolysis of cyclohexane in the presence of NzO and SF6 have been examined by determining the yields of liquid products. When we added up t o 0.3 M NzO, the hydrogen yield was reduced from its initial yield of 5.5 G units t o 2.5 G units.The nitrogen yields were about twice the decrease in hydrogen yields. Bicyclohexyl and cyclohexene yields increased from their initial values t o 2.27 and 3.50 G units respectively. When we added up to 0.12 M SFe, all the vields were decreased t o about one half of their initial value.These results may be interpreted in terms of Dyne's general mechanism for the radiolysis of hydrocarbons if two cyclohexyl radicals are produced for every electron scavenged by Nz0, b u t if none are produced for electrons scavenged by S F + I t is suggested that the total electron yield in pure cyclohexane is about 4.1 G units, of which only 3.0 G units produce hydrogen. The other 2.5 G units of hydrogen from the radiolysis of pure cyclohexane are presumed t o arise from direct excitation.

“…The results of Dyne and his co-workers on the first-order yield of D 2 (G1(D)) from 5% C6D12 in C6H12 are of some help. They found that G1(D) from the liquid is about 0.27 (7), and from the solid is 0.45 to 0.50 (5). Since the total "molecular" yield in liquid cyclohexane is about 1.0 (1, 8), .…”

Section: Lrntroductionmentioning

confidence: 99%

γ-Radiolysis of cyclohexane with electron scavengers. II. Solid cyclohexane at 77 °K

Sagert¹

1968

The r-radiolysis of homogeneous solid solutions of SF6 and NzO in cyclohexane has been examined at 77 "K. With SF6, yields of the major products, hydrogen, bicyclohexyl, and cyclohexene, were all reduced, and no large yields of other products were observed. Thus, since SF6 reduces hydrogen yields by capturing electrons, combination of the SF6 anion and cyclohexane cation does not lead to bond breaking. Experimental evidence suggests that the ratio of disproportionation to combination of cyclohexyl radicals in solid cyclohexane atWith N 2 0 , hydrogen yields are decreased to 3.5 G units, but large yields of cyclohexene, bicyclohexyl, and cyclohexanol (4.7, 2.0, and 1.0 G units respectively) are produced. Thus combination of 0-and the cyclohexane cation leads to a great deal of bond breaking. The yields are explained by a mechanism similar to Dyne's mechanism for the radiolysis of hydrocarbons. It was, however, necessary to assume that excited states of cyclohexane formed directly behave differently from those formed by electroncation combination.Canadian Journal of Chemistry, 46, 89 (1968) lrntroduction other rather than abstract hydrogen from the Charge separation is important in the radial-ll~drocarbon at low temperatures. On the other ysis of liquid l~y d r~c a r b o n~. This charge separa-hand, Dyne Denhastog ( 5 ) found evidence tion has been studied in our laboratory by using that the hydrogen Precursors were probably N 2 0 , SFG (I), and CC14 (2) to capture the major "hot" hydrogen atoms which had a high negatively cllarged species, the electron. ~y d r o -probability of reactioll before being moderated gen yields were reduced, but with N 2 0 and cc14, to therlnal energies. It was hoped that by using secondary reactions occurred which resulted N2°