Spectra, yields, and photolability of cations, carbanions, radicals, and scavenger anions in. gamma. -irradiated alkane glasses

Journal Article · Thu Jan 24 04:00:00 EST 1980 · J. Phys. Chem.; (United States)

DOI:https://doi.org/10.1021/j100439a005· OSTI ID:5068044

Bhattacharya, D; Willard, J E

The overlapping spectra of the cations, carbanions, and radicals responsible for the broad observed spectrum from 200 to 800 nm in ..gamma..-irradiated alkane glasses at cryogenic temperatures have been resolved in 3-methylpentane (3MP) and 2-methylpentane (2MP). Extinction coefficients have been assigned to these species and to the scavenger anions SF/sub 6//sup -/, Cl/sub 2//sup -/, and Br/sub 2//sup -/ formed in the glasses. The lambda/sub max/ values in 3MP, and the extinction coefficients are as follows: 3MP/sup +/, 490 nm, 153 M/sup -1/ cm/sup -1/; R., 218 nm, 1675 M/sup -1/ cm/sup -1/; R:/sup -/, 240 nm, 6300 M/sup -1/ cm/sup -1/; SF/sub 6//sup -/, epsilon/sup 350/ = 573 M/sup -1/ cm/sup -1/; Cl/sub 2//sup -/, 350 nm, 3257 M/sup -1/ cm/sup -1/; Br/sub 2//sup -/, 365 nm, 4238 M/sup -1/ cm/sup -1/. In 3MP which has received a 2.8 x 10/sup 19/ eV g/sup -1/ ..gamma.. dose at 68 K, G(R:/sup -/) is approx. 0.3. Nearly all of the e/sup -/ produced by photoejection from the R:/sup -/ are trapped by the matrix rather than reacting with cations. When the e/sub t//sup -/ are mobilized by IR light, approx. 12% react with R. to form R:/sup -/ and 88% neutralize cations. The ratio of radicals formed by the neutralization process to electrons neutralized is 0.27. The trapped cations can be removed by exposure to light in their absorption band. In 3MP and 2MP containing both the electron scavenger SF/sub 6/ and the positive charge scavenger 2MP-1, G(cations) = G(anions) = 5.4 +- 0.5. 8 figures, 3 tables.

• Research Organization: Univ. of Wisconsin, Madison
• OSTI ID: 5068044
• Journal Information: J. Phys. Chem.; (United States), Journal Name: J. Phys. Chem.; (United States) Vol. 84:2; ISSN JPCHA
• Country of Publication: United States
• Language: English

Related Subjects

38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEAR CHEMISTRY
400600* -- Radiation Chemistry
ABSORPTION SPECTRA
ALKANES
ANIONS
BROMIDES
BROMINE COMPOUNDS
CATIONS
CHARGED PARTICLES
CHEMICAL RADIATION EFFECTS
CHEMICAL REACTION KINETICS
CHEMICAL REACTION YIELD
CHEMICAL REACTIONS
CHEMISTRY
CHLORIDES
CHLORINE COMPOUNDS
DATA
DECOMPOSITION
ELECTROMAGNETIC RADIATION
EXPERIMENTAL DATA
FLUORIDES
FLUORINE COMPOUNDS
G VALUE
GAMMA RADIATION
HALIDES
HALOGEN COMPOUNDS
HYDROCARBONS
INFORMATION
INFRARED SPECTRA
IONIZING RADIATIONS
IONS
KINETICS
LOW TEMPERATURE
NUMERICAL DATA
ORGANIC COMPOUNDS
RADIATION CHEMISTRY
RADIATION EFFECTS
RADIATIONS
RADICALS
RADIOLYSIS
REACTION KINETICS
SCAVENGING
SPECTRA
SULFUR COMPOUNDS
SULFUR FLUORIDES
TEMPERATURE DEPENDENCE
YIELDS