Theoretical study of the molecular conformations, vibrational frequencies and thermochemistry of the FC(O)OOO(O)CF, FS(O2)OOO(O2)SF and FC(O)OOO(O2)SF trioxides

Formation and dissociation kinetics of the FC(O)OOO(O)CF, FS(O2)OOO(O2)SF and FC(O)OOO(O2)SF trioxides: A theoretical study

“…As Figure 1 These D e values are considerably smaller than the one obtained from the theoretical thermochemical analysis of Ref. [28] (see Table 1). …”

“…For all cases, the internal rotations of the trioxides were considered as hindered motions. The corresponding torsional potential curves, calculated in a previous work, are summarized in Figures A and B of the Supplementary material [28]. Table 3 Phase space theory rate coefficients (in cm 3 molecule −1 s −1 ), thermal rigidity factors and rate coefficients (in cm 3 molecule −1 s −1 ) calculated using the G3S(MP2)//B3LYP/6-311+G(3df) potentials.…”

“…A five times smaller high pressure rate coefficient, Table 1 Molecular input data employed in the kinetics calculations. Structural parameters ( in g mol −1 ; rCM in Å; angle in degree; rotational constants B1 and B2 in cm −1 ; and ˇ in Å −1 ) and harmonic vibrational frequencies (in cm −1 ) computed at the B3LYP/6-311+G(3df) level [28]. De and H0 (in kcal mol −1 ) obtained from isodesmic reactions at the G3(MP2)//B3LYP/6-311+G(3df) and G4(MP2) levels [28].…”

“…The predicted well-depth at 298 K of 25.0 kcal mol −1 suggests that this trioxide presents a considerable thermal stability [28]. As a comparison, the O O bond dissociation enthalpy for the well known related peroxide FS(O 2 )OO(O 2 )SF is 22.1 kcal mol −1 [18].…”

“…In addition, from conformational and thermochemical theoretical studies, a FC(O)O OO(O)CF bond dissociation enthalpy at 298 K of 32.2 kcal mol −1 has been derived [12,28].…”