Rate constants estimation for the reaction of hydrofluorocarbons and hydrofluoroethers with OH radicals

Urata, Shingo; Takada, Akira; Uchimaru, Tadafumi; Chandra, Asit K.

doi:10.1016/s0009-2614(02)01718-9

Cited by 72 publications

(74 citation statements)

References 24 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In comparison to the results of TST and CVT, the CVT/SCT rate constants shown in Figure 5 a are in much better agreement with the reliable data of Chandra and co-workers [11] (1.5 times at 298 K) and Hsu et al [9] (within a factor of 1.2-2.0 in 298-393 K), while the calculated data is ten times lower than the result obtained by Huie and his co-workers [10] at 296 K. The rate constant at 298 K for Reaction (1) . For the reaction with Cl atoms, our calculated result at room temperature described in Figure 5(b) and Table 5 , is in excellent consistency with the experimental value reported by Inoue et al, [13] 2.3 10 À17 cm 3 molecule À1 s…”

Section: Rate Constant Calculationssupporting

confidence: 87%

“…[10] Urata and co-workers [11] theoretically evaluated the rate coefficient at room temperature by using the estimated bond dissociation enthalpy (BDE) and a modification of Heicklen's empirical equation.…”

Section: Introductionmentioning

confidence: 99%

“…In addition, [9] 104.27, [11] 103.5, [37] ). It is seen that the calculated CÀO bond energy in CH 3 OCH 3 at the G3(MP2)//B3LYP/6-311G(d,p) level, 82.8 kcal mol…”

mentioning

confidence: 99%

See 2 more Smart Citations

Theoretical Study of the Reactions of CF₃OCHF₂ with the Hydroxyl Radical and the Chlorine Atom

Liu

et al. 2004

ChemPhysChem

View full text Add to dashboard Cite

Theoretical investigations are carried out on the reaction mechanism of the reactions of CF3OCHF2 (HFOC-125) with the OH radials and Cl atoms, as well as the heats of formation of CF3OCHF2 and CF3OCF2. The electronic structure information on the potential energy surface for each reaction is obtained at the B3LYP/6-311G(d,p) level, and energetic information is further refined by G3(MP2) theory. The direct dynamics calculation of the hydrogen abstraction reactions are also performed at the G3(MP2)//B3LYP/ 6-311G(d,p) level. The classical energy profile is corrected by interpolated single-point energies (ISPE) approach, incorporating the small-curvature tunnelling effect (SCT) calculated by the variational transition-state theory (VTST). The rate constants are in good agreement with the experimental data and are found to be k1 = 4.95 x 10(-30)T(5.40)exp(-347/T) and k2 = 1.86 x 10(-23)T(3.43)exp(-1579/T) cm3 molecule(-1)s(-1) over the temperature range 200-2000 K. The rate constants at 298 K for these two reactions are 3.38 x 10(-16) and 2.80 x 10(-17) cm3 molecule(-1)s(-1), respectively. Using group-balanced isodesmic reactions as working chemical reactions, the standard enthalpies of formation for CF3OCHF2 and CF3OCF2 are -312.3 +/- 1.0 and -257.3 +/- 1.0 kcalmol(-1), respectively, evaluated by G3(MP2) theory based on the B3LYP/6-311G(d,p) geometries. The theoretical studies provide rate constants of the title reactions and the enthalpies of the species, which are important parameters in determining the atmospheric lifetime and the feasible pathways for the loss of HFOC-125.

show abstract

Section: Rate Constant Calculationssupporting

confidence: 87%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Theoretical Study of the Reactions of CF₃OCHF₂ with the Hydroxyl Radical and the Chlorine Atom

Liu

et al. 2004

ChemPhysChem

View full text Add to dashboard Cite

show abstract

“…12 Therefore, considerable attention has been paid in recent years to perform experimental and theoretical studies on the decomposition kinetics of HFEs. [13][14][15][16] Tropospheric degradation is expected to be initiated mainly by the attack of OH radicals in the gas phase 17 and CF 3 CH 2 OCF 3 (HFE-246cb2) may undergo H atom abstraction as follows.…”

Section: Introductionmentioning

confidence: 99%

Hydrogen-Atom Abstraction Reaction of CF₃CH₂OCF₃by Hydroxyl Radical

Singh¹,

Mishra²,

Rao³

2010

Bulletin of the Korean Chemical Society

View full text Add to dashboard Cite

Theoretical investigations are carried out on the title reaction by means of ab-initio and DFT methods. The optimized geometries, frequencies and minimum energy path are obtained at UB3LYP/6-311G(d,p) level. Single point energy calculations are performed at MP2 and MP4 levels of theory. Energetics are further refined by calculating the energy of the species with a modified Gaussian-2 method, G2M(CC,MP2). The rate constant of the reaction is calculated using Canonical Transition State Theory (CTST) utilizing the ab-initio data obtained during the present study and is found to be 5.47 × 10 -12 cm 3 molecule -1 s -1 at 298 K and 1 atm.

show abstract

“…To the best of our knowledge, no experimental measurements for the determination of rate coefficients for its reaction with OH radical were reported. Theoretical investigations of CH 3 OCH 2 F were reported by Urata et al, Blower et al, and Nam et al [7][8][9]. Urata et al [7] have reported the rate coefficient for its reaction with OH radical at 298 K to be 1.92 Â 10 À13 cm 3 molecule À1 s…”

mentioning

confidence: 99%

Kinetic parameters for the reaction of hydroxyl radical with CH₃OCH₂F (HFE‐161) in the temperature range of 200–400 K: Transition state theory and Ab initio calculations

Kaliginedi

Ali

Rajakumar

2011

Int J of Quantum Chemistry

View full text Add to dashboard Cite

Rate coefficients for the reaction of the hydroxyl radical with CH 3 OCH 2 F (HFE-161) were computed using transition state theory coupled with ab initio methods, viz., MP2, G3MP2, and G3B3 theories in the temperature range of 200-400 K. Structures of the reactants and transition states (TSs) were optimized at MP2(FULL) and B3LYP level of theories with 6-31G* and 6-311þþG** basis sets. The potential energy surface was scanned at both the level of theories. Five different TSs were identified for each rotamer. Calculations of Intrinsic reaction coordinates were performed to confirm the existence of all the TSs. The kinetic parameters due to all different TSs are reported in this article. The rate coefficients for the title reaction were computed to be k ¼ (9 6 1.08) Â 10

show abstract

Rate constants estimation for the reaction of hydrofluorocarbons and hydrofluoroethers with OH radicals

Cited by 72 publications

References 24 publications

Theoretical Study of the Reactions of CF₃OCHF₂ with the Hydroxyl Radical and the Chlorine Atom

Theoretical Study of the Reactions of CF₃OCHF₂ with the Hydroxyl Radical and the Chlorine Atom

Hydrogen-Atom Abstraction Reaction of CF₃CH₂OCF₃by Hydroxyl Radical

Kinetic parameters for the reaction of hydroxyl radical with CH₃OCH₂F (HFE‐161) in the temperature range of 200–400 K: Transition state theory and Ab initio calculations

Contact Info

Product

Resources

About

Rate constants estimation for the reaction of hydrofluorocarbons and hydrofluoroethers with OH radicals

Cited by 72 publications

References 24 publications

Theoretical Study of the Reactions of CF3OCHF2 with the Hydroxyl Radical and the Chlorine Atom

Theoretical Study of the Reactions of CF3OCHF2 with the Hydroxyl Radical and the Chlorine Atom

Hydrogen-Atom Abstraction Reaction of CF3CH2OCF3by Hydroxyl Radical

Kinetic parameters for the reaction of hydroxyl radical with CH3OCH2F (HFE‐161) in the temperature range of 200–400 K: Transition state theory and Ab initio calculations

Contact Info

Product

Resources

About

Theoretical Study of the Reactions of CF₃OCHF₂ with the Hydroxyl Radical and the Chlorine Atom

Theoretical Study of the Reactions of CF₃OCHF₂ with the Hydroxyl Radical and the Chlorine Atom

Hydrogen-Atom Abstraction Reaction of CF₃CH₂OCF₃by Hydroxyl Radical

Kinetic parameters for the reaction of hydroxyl radical with CH₃OCH₂F (HFE‐161) in the temperature range of 200–400 K: Transition state theory and Ab initio calculations