Enthalpies of formation of the benzyloxyl, benzylperoxyl, hydroxyphenyl radicals and related species on the potential energy surface for the reaction of toluene with the hydroxyl radical

  • Oscar N. VenturaEmail author
  • Martina Kieninger
  • Zoi Salta
  • Agnie M. Kosmas
  • Vincenzo Barone
Regular Article
Part of the following topical collections:
  1. 11th Congress on Electronic Structure: Principles and Applications (ESPA-2018)


The reaction of toluene (T) with ·OH produces addition products as well as the benzyl radical (TR). TR can react with ·OH or O2 to produce oxygenated species, for many of which there is no experimental information available. We present here theoretically determined heats of formation (HFs) of 17 such species using the non-isodesmic reactions on the potential energy surface of TR + O2 and T + ·OH +O2. For those species the experimental HFs of which are known, we obtained a good correlation between experimental and theoretical values at the G4 (r2 = 0.999) and M06/cc-pVQZ (r2 = 0.997) levels, thus showing the goodness of the methods used. Experimentally unknown HFs of other radicals (benzyloxyl, spiro [1,2-dioxetane benzyl], hydroxyphenyl and benzylperoxyl) and closed-shell species (salicylic alcohol, benzo[b]oxetane and p-hydroxy cyclohexa-2,5-dienone) were later determined using those methods.


Toluene Atmospheric chemistry Benzyl radical Enthalpies of formation DFT 



PEDECIBA (Uy), CSIC (UdelaR, Uy) and ANII (Uy) are gratefully acknowledged for sustained funding of the theoretical atmospheric chemistry program in which the toluene project is included. Some of the calculations reported in this paper were performed in ClusterUY, a newly installed platform for high-performance scientific computing at the National Supercomputing Center, Uruguay.

Supplementary material

214_2019_2500_MOESM1_ESM.docx (21 kb)
Supplementary material 1 (DOCX 21 kb)


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Authors and Affiliations

  1. 1.Computational Chemistry and Biology Group, CCBG – DETEMA, Facultad de QuímicaUdelaRMontevideoUruguay
  2. 2.SMART LabScuola Normale SuperiorePisaItaly
  3. 3.Physical Chemistry Sector, Department of ChemistryUniversity of IoanninaIoanninaGreece

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