الفهرس 
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Abstract
The present work aims to study the thermochemistry and kinetics
of 2-butanol decomposition either through bimolecular oxidation using
methyl, hydroxyl, hydroperoxyl and hydrogen radicals. The obtained
results were compared with those obtained for n-butanol because of
molecular weight similarity of the two compounds and to show the effect
of presence etheric oxygen upon the abstraction mechanism. 2-butanol
has many advantages includes high internal energy, low vapor pressure,
low toxicity and hydropholic than ethanol. The potential energy
diagrams for all of the investigated channels were constructed at BMK,
CBS-APNO, G3, G3B3, G4MP2, and CBS-QB3 levels of theory. Finally,
rate constant calculations for all channels at different temperatures were
computed using the conventional transition state theory (TST) with
Wigner correction.
All channels of oxidation of 2-butanol by H radical are exothermic at
CBS-QB3. Based on the calculated energy barriers for oxidation channels,
the order for H-abstraction reactions is the order of site is given Cα< Cβ <
Cϒ < Cβm < O at CBS-QB3. H-abstraction from Cα has the lowest energy
barrier because it forms the most stable radical due to the presence of
higher degree of hyperconjugation with the five C-H bonds. Oxidation of
2-butanol by OH show H-abstraction reactions is the order of site is given
Cα< Cβ < Cϒ < Cβm < O at CBS-QB3. H-abstraction from Cα has the
lowest energy barrier because it forms the most stable radical that is
stabilized due to the presence of higher degree of hyperconjugation, five
C-H bonds can interact with the radical center. Moreover, some transition
states can be stabilized by the presence of intramolecular hydrogen bond
between the attacking hydroperoxyl radical and the alcoholic OH.