Related Experiment Video
Updated: Mar 13, 2026

Analyzing the Photo-oxidation of 2-propanol at Indoor Air Level Concentrations Using Field Asymmetric Ion Mobility Spectrometry
Published on: June 14, 2018
Photoelectron spectroscopy of the hydroxymethoxide anion, H2C(OH)O
Allan M Oliveira1, Julia H Lehman1, Anne B McCoy2
1JILA and Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309, USA.
Abstract:
We report the negative ion photoelectron spectroscopy of the hydroxymethoxide anion, H2C(OH)O-. The photoelectron spectra show that 3.49 eV photodetachment produces two distinct electronic states of the neutral hydroxymethoxy radical (H2C(OH)O⋅). The H2C(OH)O⋅ ground state (X̃ 2A) photoelectron spectrum exhibits a vibrational progression consisting primarily of the OCO symmetric and asymmetric stretches, the OCO bend, as well as combination bands involving these modes with other, lower frequency modes. A high-resolution photoelectron spectrum aids in the assignment of several vibrational frequencies of the neutral H2C(OH)O⋅ radical, including an experimental determination of the H2C(OH)O⋅ 2ν12 overtone of the H-OCO torsional vibration as 220(10) cm-1. The electron affinity of H2C(OH)O⋅ is determined to be 2.220(2) eV. The low-lying à 2A excited state is also observed, with a spectrum that peaks ∼0.8 eV above the X̃ 2A state origin. The à 2A state photoelectron spectrum is a broad, partially resolved band. Quantum chemical calculations and photoelectron simulations aid in the interpretation of the photoelectron spectra. In addition, the gas phase acidity of methanediol is calculated to be 366(2) kcal mol-1, which results in an OH bond dissociation energy, D0(H2C(OH)O-H), of 104(2) kcal mol-1, using the experimentally determined electron affinity of the hydroxymethoxy radical.
Related Concept Videos
Autoxidation of Ethers to Peroxides and Hydroperoxides
UV–Vis Spectroscopy: Molecular Electronic Transitions
Mass Spectrometry: Alcohol Fragmentation
Electron Paramagnetic Resonance (EPR) Spectroscopy: Organic Radicals
Oxidative Cleavage of Alkenes: Ozonolysis
Ozone is a symmetrical bent molecule stabilized by a resonance structure.
Hydroboration-Oxidation of Alkenes

