Organic radical-radical reactions. Disproportionation vs. combination

Gibian, Morton J.; Corley, Robert C.

doi:10.1021/cr60285a002

Cited by 257 publications

(152 citation statements)

References 6 publications

Supporting

Mentioning

139

Contrasting

Order By: Relevance

“…Similar behavior has been observed with other radicals (2). This difference between gas and liquid phases is not easily explained.…”

Section: Resultssupporting

confidence: 81%

“…Values of kd/kc, the rate constant ratio for disproportionation and combination, range from essentially zero for methyl radicals (insofar as this ratio may be observed in this system) to 3.1 for two t-butyl radicalsilJ. The factors determining this ratio have been much discussed but no comprehensive interpretation has yet evolved (2). The most promising empirical relation appears to be the linear dependence of log kd/kc on SdO -S : , the entropy difference between the products of disproportionation and of combination (3, 4).…”

Section: Introductionmentioning

confidence: 97%

See 1 more Smart Citation

The Temperature Dependence of the Ratio k_d/k_c for Ethyl Radicals

Hooper¹,

Simon²,

Back³

1975

Can. J. Chem.

View full text Add to dashboard Cite

The ratio of the rate constants for disproportionation and combination for ethyl radicals, k d / k kd 2C2Hs + C2H4 + C2Hs has been measured over the temperature range 298-173 K in the gas phase. Ethyl radicals were produced by direct photolysis of ethylenefollowed by addition of hydrogen atoms to ethylene. At low temperatures the only important reactions of the radicals were combination and disproportionation. The ratio kd/kc was obtained from measurements of the rates of formation of ethane, butane, and butene. No change in the ratio kd/k, was observed over the temperature range studied, leading to the conclusion that Ed -E, = 0, within the experimental error. The significance of this result is discussed in relation to other measurements in both gas and liquid phase and to the nature of the transition state for this reaction.

show abstract

“…Similar behavior has been observed with other radicals (2). This difference between gas and liquid phases is not easily explained.…”

Section: Resultssupporting

confidence: 81%

Section: Introductionmentioning

confidence: 97%

The Temperature Dependence of the Ratio k_d/k_c for Ethyl Radicals

Hooper¹,

Simon²,

Back³

1975

Can. J. Chem.

View full text Add to dashboard Cite

show abstract

“…In accordance with the known disproportionation (2C 2 H 5 Á → C 2 H 4 C 2 H 6 )/combination (2C 2 H 5 Á → n-C 4 H 10 ) rate ratio k d /k c for the ethyl radical ($0.13), 21 a clean M-C homolysis would have yielded n-butane in a large excess over equal amounts of ethane and ethene. The observed dominance of ethene over both n-butane and ethane reveals that more than 90% of the ethene in both the KrF and ArF laser photolyses must be produced via a different channel, i.e.…”

Section: Photolysis Mechanismsupporting

confidence: 61%

Atmospheric pressure chemical vapour deposition of selenium and tellurium films by UV laser photolysis of diethyl selenium and diethyl tellurium

Pola

Bastl

Šubrt

et al. 2001

Applied Organom Chemis

View full text Add to dashboard Cite

Excimer laser-induced photolysis of gaseous diethyl selenium and diethyl tellurium (C 2 H 5 ) 2 M (M = Se, Te) is controlled by cleavage of both M-C bonds, it yields C 1 -C 4 hydrocarbons (ethene as major product) and results in chemical vapour deposition of selenium films and nanosized tellurium powder. The selenium and tellurium properties were characterized by X-ray photoelectron spectroscopy and Scanning electron Microscopy techniques.

show abstract

“…Additional evidence for the unimportance of cage dimerizations are the high disproportionationrecombination ratios found for most of the radicals involved 9. 23 ) and the high fluid-ities 23 ) of the medium at the high temperatures which were required for most reactions 9'.…”

Section: Methodsmentioning

confidence: 99%