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Heats of Formation of Halomethanes Based on Quantum Chemical Computations_290820.pdf (1.57 MB)
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Standard Molar Enthalpies of Formation of Halomethanes Based on Quantum Chemical Computations

preprint
submitted on 31.08.2020 and posted on 01.09.2020 by Konstantinos Kalamatianos
Accurate calculations of standard molar enthalpies of formation (ΔΗf°)m(g) and carbon-halogen bond dissociation enthalpies, BDE, of a variety of halomethanes with relevance on several atmospheric chemical processes and particularly to ozone destruction, were performed in the gas phase at 298.15 K. The (ΔΗf°)m(g) of the radicals formed through bond dissociations have also been computed. Ab initio computational methods and isodesmic reaction schemes were used. It is found that for the large majority of these species, the gold standard method of quantum chemistry (CCSD(T)) and even MP2 are capable to predict enthalpy values nearing chemical accuracy provided that isodesmic reaction schemes are used. New estimates for standard molar enthalpies of formation and BDE are suggested including for species that to our knowledge there are no experimental (ΔΗf°)m(g) (CHCl2Br, CHBr2Cl, CHBrCl, CHICl, CHIBr) or BDE values (CHCl2Br, CHBr2Cl, CHBrCl, CHICl, CHIBr) available in the literature. The method and calculational procedures presented may profitably be used to obtain accurate (ΔΗf°)m(g) and BDE values for these species.

History

Email Address of Submitting Author

kgkalamatianos@gmail.com

Institution

I.Y.A.

Country

GREECE

ORCID For Submitting Author

https://orcid.org/0000-0002-0276-6531

Declaration of Conflict of Interest

No potential conflict of interest is reported by the author.

Version Notes

E1_31082020

Exports