Energy-Resolved Collision-Induced Dissociation of Peroxyformate Anion: Enthalpies of Formation of Peroxyformic Acid and Peroxyformyl Radical

• Published in: The journal of physical chemistry. A, Molecules, spectroscopy, kinetics, environment, & general theory Vol. 117; no. 6; pp. 1021 - 1029
• Main Authors: Nickel, Alex A, Lanorio, Jerry G, Ervin, Kent M
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 14.02.2013
• Subjects: Anions; Anions - chemistry; Bonding; Dissociation energy; Enthalpy; Formates - chemistry; Formations; Free energy; Free Radicals - chemistry; Heat of formation; Quantum Theory; Radicals; Tandem Mass Spectrometry; Thermodynamics
• ISSN: 1089-5639; 1520-5215
• DOI: 10.1021/jp302089q

We measure the oxygen–oxygen bond dissociation energy of the peroxyformate anion (HCO3 –) using energy-resolved collision-induced dissociation with a guided ion beam tandem mass spectrometer. The analysis of the dissociation process from HCO3 – (1A′) to HCO2 – (1A2) + O(3P) requires consideration of the singlet–triplet crossing along the reaction path and of the competing OH– and O2H– product channels. The measured oxygen–oxygen bond dissociation energy is D 0(HCO2 ––O) = 1.30 ± 0.13 eV (126 ± 12 kJ/mol). This threshold energy measurement is used in thermochemical cycles to derive the enthalpies of formation for peroxyformic acid, Δf H 0(HCO3H) = −287 ± 19 kJ/mol, and peroxyformyl radical, Δf H 0(HCO3 •) = −98 ± 12 kJ/mol. These values are in good agreement with computational energies.