36477-99-3Relevant academic research and scientific papers
The formation and destruction of H3O-
Miller, Thomas M.,Viggiano, A. A.,Miller, Amy E. Stevens,Morris, Robert A.,Henchman, Michael,et al.
, p. 5706 - 5714 (1994)
We report the first measurements of rate constants for formation and reaction of the Ion Phys. 49, 311 (1983)>, namely, dehydrogenation of formaldehyde by hydroxide to form hydrated-hydride ion and carbon monoxide.The OD- + H2CO reaction is about 35percent efficient at 298 K, with OD-/OH- exchange occurring in about half the reactions.H3O- was observed to undergo thermal dissociation in a helium carrier gas at room temperature with a rate constant of 1.6 * 10-12 cm3 s-1.We also studied a new reaction in which H3O- is formed: The association of OH- with H2 in a He carrier gas at low temperatures.The rate coefficient for this ternary reaction is 1*10-30 cm6 s-1 at 88 K.Rate coefficients and product branching fractions were determined for H3O- reactions with 19 neutral species at low temperatures (88-194 K) in an H2 carrier.The results of ion-beam studies, negative-ion photoelectron spectroscopy, and ion-molecule reaction data allow us to specify the hydride-water bond energy D0298(H- - H2O) = 14.4+/-1.0 kcal mol-1 (0.62+/-0.04 eV).The heat of formation of H3O-, -37.5+/-1.0 kcal mol-1, and the proton affinity of H3O-, 386.0+/-1.0 kcal mol-1, are derived from these results.Dissociation of H3O- into OH- and H2 requires 4.5+/-1.0 kcal mol-1 energy.
