Thermodynamics and kinetics of 1-fluoro-2-methoxypropane vs Bromine monoxide radical (BrO): A computational view

Document Type : Research Article

Authors

1 Chemistry, Physical science, Ahmadu Bello University, Zaria, Nigeria

2 Chemistry, Physical, Ahamdu Bello University, Zaria, Nigeria

3 Chemistry, Physical Ahmadu Bello University, Zaria, Nigeria

4 Chemistry, Physical sciences, ABU, Zaria, Nigeria.

5 Chemistry, Natural science, IBB, Lapai, Nigeria

Abstract

CFCs containing volatile compounds are detrimental to atmospheric environment and to all living organisms. These compounds are frequently reported to be chemically stable/inert. Also their photodissociation reaction results to reasonable amount of Chlorine atoms formation in the stratospheric part of atmosphere. This eventually bring out depletion of Ozone (lives and properties protecting compound) in the stratosphere. In order to cope this environmental havoc, there is need to find substitutable compounds for CFCs and possibly predict their atmospheric effects. Ethers when fluorinated can serve as CFCs substitute. Therefore, in this work, an Insilco investigation was conducted on the thermochemistry, mechanism and kinetics of the Hydrogen abstraction reactions of partially fluorinated isopropyl methyl ether (1-fluoro-2-methoxypropane i.e. (CH2FCH(OCH3)CH3)) with Bromine monoxide radical (BrO.) using the Density Functional Theory (DFT) based M06-2X/6-311++G** strategy. To computationally refine/improve the energy data, the single-point calculations (DFT/M06-2X/6-311++G(2df,2p) were immediately executed on the reacting species involved. The Monte Carlo search on the investigating CH2FCH(OCH3)CH3 showed nine conformers with the lowest global minimum configuration being studied. The results of this investigation showed that the atmospheric oxidation reaction of CH2FCH(OCH3)CH3 with the BrO radical proceeded in four (4) plausible reaction routes. The computed total theoretical rate of 7.95*〖10〗^(-11) M-1 sec-1, the first of its kind with BrO radical was recorded. The atmospheric lifetime/global warming potential of 1.35*10-2 days/72.8 were also reported. The potential energy surface (PES) for each reaction route with the BrO radical was constructed at absolute temperature of 298.15 K.

Graphical Abstract

Thermodynamics and kinetics of 1-fluoro-2-methoxypropane vs Bromine monoxide radical (BrO): A computational view

Keywords


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