Institutions | About Us | Help | Gaeilge
rian logo


Mark
Go Back
Enthalpies of formation and bond dissociation energies of lower alkyl hydroperoxides and related hydroperoxy and alkoxy radicals
Simmie, John M.; Black, GrĂ¡inne; Curran, Henry J.; Hinde, John P.
The enthalpies of formation and bond dissociation energies, D(ROO-H), D(RO-OH), D(RO-O), D(R-O-2) and D(R-OOH) of alkyl hydroperoxides, ROOH, alkyl peroxy, RO, and alkoxide radicals, RO, have been computed at CBS-QB3 and APNO levels of theory via isodesmic and atomization procedures for R = methyl, ethyl, n-propyl and isopropyl and n-butyl, tert-butyl, isobutyl and sec-butyl. We show that D(ROO-H) approximate to 357, D(RO-OH) approximate to 190 and D(RO-O) approximate to 263 kJ mol(-1) for all R, whereas both D(R-OO) and D(R-OOH) strengthen with increasing methyl substitution at the cc-carbon but remain constant with increasing carbon chain length. We recommend a new set of group additivity contributions for the estimation of enthalpies of formation and bond energies.
Keyword(s): sulfate-reducing aquifer; set model chemistry; gas-phase acidity; thermochemical properties; peroxy-radicals; group additivity; thermodynamic properties; natural attenuation; united-states; kinetics
Publication Date:
2018
Type: Journal article
Peer-Reviewed: Unknown
Institution: NUI Galway
Publisher(s): American Chemical Society (ACS)
First Indexed: 2019-03-23 06:23:12 Last Updated: 2019-09-20 06:46:15