C$sup 13$ AND DEUTERIUM ISOTOPE EFFECTS IN THE PHOTOLYSIS OF METHYL AND ETHYL BROMIDE

Journal Article · Wed Apr 01 04:00:00 EST 1959 · Journal of Chemical Physics (U.S.)

DOI:https://doi.org/10.1063/1.1730138· OSTI ID:4266685

Gordus, A A; Bernstein, R B

Relative rates of formation of isotopic radicals in thc photolysis of gaseous methyl and ethyl bromide have been measured. Photolyses (2537 A) were carried out in a large excess of cyclopentane. Methyl (or ethyl) radicals formed ln the primary C-Br bond scission abstract H from cyclopentane to fornm methane (or ethane). For methyl bromide, the C/sup 12//C/sup 13/ enrichment factor for the first fraction of the methane was l.039 sintering time 0.003. The corresponding factor for the alpha -carbon--Br rupture in ethyl bromide was 1.04l sintering time 0.004. In the deuterium experiments, CH/sub 3/Br-CD/sub 3/ Br mixtures in excess cyclopentane were photolyzed. The H/D fractionation factor (based on CH/sub 4//CD/sub 3/H) was l.4l sintering time 0.0l. The difference in rates of formation of isotopic radicals ls due to the difference in ultraviolet absorption coefficients of the isotopic alkyl bromides. At 2537 A the observed ratio of the extinction coefficient of CH/sub 3/Br relative to that of CD/sub 3/Br is 1.38 sintering time 0.05. (auth)

• Research Organization: Univ. of Michigan, Ann Arbor
• Sponsoring Organization: USDOE
• NSA Number: NSA-13-013350
• OSTI ID: 4266685
• Journal Information: Journal of Chemical Physics (U.S.), Journal Name: Journal of Chemical Physics (U.S.) Vol. Vol: 30; ISSN JCPSA
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

ABSORPTION
BROMINATED HYDROCARBONS
CARBON 12
CARBON 13
CHEMICAL REACTIONS
CHEMISTRY
CYCLOALKANES
DECOMPOSITION
DEUTERIUM
ENRICHMENT
ETHYL RADICALS
FREQUENCY
GASES
ISOTOPE EFFECTS
METHYL RADICALS
ORGANIC BROMINE COMPOUNDS
PENTANE
PHOTOCHEMISTRY
PRODUCTION
REACTION KINETICS
ULTRAVIOLET RADIATION