Quantum Mechanical and Rice−Ramsperger−Kassel−Marcus Investigation of the Thermal Unimolecular Decomposition of CF₂BrO and CF₂ClO Radicals

Abstract

Quantum mechanical and Rice−Ramsperger−Kassel−Marcus calculations are carried out to study the thermal unimolecular decomposition of CF2XO radicals (X = Br, Cl). Two kinds of dissociation mechanisms are possible, carbon−halogen bond scission and intramolecular three-center XF elimination. It should be noted that the three-center direct XF elimination has only been able to be characterized at the B3LYP level. X-atom elimination is shown to be the dominant reaction pathway, whereas C−F bond scission and XF elimination have been found to exhibit high energy barriers. On the basis of the ab initio data, energy-specific rate constants k(E) and thermal rate constants k(T,P) are evaluated using master equation numerical analysis.

Sugar Synthesis from a Gas-Phase Formose Reaction

“…More information about these methods is available elsewhere (Foresman and Frisch, 1996;Jalbout et al, 2004). These combinations of methods have been shown to produce reasonably good agreement with the experiment and are generally quite accurate (Drougas et al, 2003(Drougas et al, , 2004Jalbout et al, 2006;Zhou et al, 2006). These calculations were done in the gas phase, and assume that the molecules do not interact with the solvent.…”

Structural and heat of formation studies of halogenated methyl hydro-peroxides

“…The alkylperoxy radicals formed, present a rich chemistry and give self-reactions or react with other active species producing a variety of oxidized products [2,[4][5][6][7][8]. In low concentrations of NO x , the most important reactions involve the abundant hydroperoxy radicals [2,9] leading to the production of ROOH…”

Theoretical Study on Structures and Properties of N2O···HOCl Complexes

“…This point has been reported by Wei et al 41 Recently, it has been reported that DFT and ab initio methods could accurately calculate structures and energies for chlorine (Cl) containing halogen compounds. 42,43 Here, according to the BSSE and ZPVE corrected interaction energy (ΔE CP＋ZPVE ) calculated at B3LYP/6-311＋＋G** level listed in Table 2, we can conclude that the stabilities of the six complexes increase in the order S1≈S4＜S2＜ S6≈S3＜S5.…”