A new publication of researchers Tam V.-T. Mai, Minh v. Duong, Hieu T. Nguyen and Lam K. Huynh was supported by fund based on Clause 1, Article 14 of Decision No. 03/ QD-KHCNTT dated January 2^nd, 2018 about promulgating the Internal Spending Rules of the Institute for Computational Science and Technology, which stipulates support for International and domestic publication. Here is an introduction to the publication of the researchers.
 
Publication of research “Detailed Kinetics of Tetrafluoroethene Ozonolysis”
 
On October 18^th, 2018, researcher of Molecular Science Lab at ICST (Tam V.-T. Mai), and his colleagues, Minh v. Duong, Hieu T. Nguyen and Lam K. Huynh have just published a research named “Detailed Kinetics of Tetrafluoroethene Ozonolysis” on “The Journal of Physical Chemistry Chemical Physics”
 
The C₂F₄ + O₃ reaction plays an important role in the oxidation process of perfluoroalkenes in the atmosphere. The detailed reaction mechanism was explored at the accurate electronic structure method, CCSD(T)/CBS//B3LYP/aug-cc-pVTZ. The 1,3-cycloaddition of O₃ with C₂F₄ to form the primary ozonide was found to be the rate-determining step of the oxidation process with a small barrier (i.e., 7.3 kcal/mol at 0 K). The temperature- and pressure-dependent behaviors of the title reaction were characterized in the range of 200 – 1000 K & 0.1 – 760 torr using the integrated deterministic and stochastic master equation/Rice–Ramsperger–Kassel–Marcus (ME/RRKM) rate model with the inclusion of the corrections for anharmonicity and tunneling treatments. It is found that the anharmonic effect plays a role in the kinetic behaviors (e.g., lower the rate by a factor of ~ two at 298 K) while the tunneling correction is insignificant. The total rate constants were found to be pressure-independent in the considered conditions, shown as k_tot(T) = 4.80×10^-23×T^2.69×exp(-2983.4 K/T) (cm³/molecule/s), which  confirms the latest experimental data by Acerboni et al. (Chem. Phys. Lett., 1999, 309, 364-368); thus this study helps to resolve a long-time controversy among the previous measurements. The sensitivity analyses on the derived rate coefficients and time-resolved species mole fraction with respect to the ab initio input parameters were also performed to further understand as well as quantify the kinetic behaviors for the title reaction.
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Fig. 7. Rate coefficients at 760 Torr with respect to the energy transfer Δ (E_down) = +100 cm1 (a); the barrier height ∆V^‡  of the TS1 channel (∆TS1 = +1 kcal mol1) (b), and TS2 channel (∆TS2 = +1 kcal mol1) (c), respectively.
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