Photoionization studies of (H2O)2 and (HF)2 producing H3O+ and H2F+ yield 7.18±0.08 eV (165.8±1.8 kcal/mole) and 4.09±0.06 eV (94.3±1.4 kcal/mole) as the proton affinities of H2O and HF, respectively. The measured ionization potential of (H2O)2, 11.21±0.09 eV, along with the known ionization potential of H2O, 12.615±0.001 eV, allow the deduction of a lower bound for the dissociation energy of (H2O)2:1.58±0.13 eV (36±3 kcal/mole). The experiments have demonstrated that photoionization of dimers is one of the most useful general methods for the determination of proton affinities.
Photoionization of dimeric polyatomic molecules: Proton affinities of H2O and HF
C. Y. Ng, D. J. Trevor, P. W. Tiedemann, S. T. Ceyer, P. L. Kronebusch, B. H. Mahan, Y. T. Lee; Photoionization of dimeric polyatomic molecules: Proton affinities of H2O and HF. J. Chem. Phys. 1 November 1977; 67 (9): 4235–4237. https://doi.org/10.1063/1.435404
Download citation file: