The unimolecular dissociation of CH3OOH is investigated by exciting the molecule in the region of its 5νOH band and probing the resulting OH fragments using laser-induced fluorescence. The measured OH fragment rotational and translational energies are used to determine the CH3OOH bond dissociation energy, which we estimate to be 42.6±1kcalmol. Combining this value with the known heats of formation of the fragments also gives an estimate for the heat of formation of CH3OOH which at 0K we determine to be ΔHf0=27±1kcalmol. This experimental value is in good agreement with the results of ab initio calculations carried out at the CCSD(T)/complete basis set limit which finds the heat of formation of CH3OOH at 0K to be ΔHf0=27.3kcalmol.

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