Supersonically Cooled Moleculear Ions in a Slit-Jet Discharge: High-Resolution Infrared Spectrscopy and Tunneling Dynamics of HD2O+
Feng Dong, D Uy, S Davis, Mark Child, David Nesbitt
Jet-cooled high-resolution infrared spectra of partially deuterated hydronium (HD2O+) in the O-H stretch region (v3 band) are obtained for the first time, exploiting the high ion densities, long absorption path lengths, and concentration modulation capabilities of the slit jet discharge spectrometer. Least-square analysis with a Watson asymmetric top Hamiltonian yields rovibrational constants and provides high level tests of ab initio molecular structure predictions. Transitions out of both lower (vd3O+) and upper (v3-O^-) tunneling levels are observed, as well as transitions across the tunneling gap (v3-O+). The v3-O+ transitions in HD2O+ acquire oscillator strength by loss of C3 symmetry, and permit both ground (27.0318(72) cm-1) and excited state (17.7612(54) cm^-1) tunneling splittings t be determined to spectroscopic precision from a single rovibrational band. The splittings and band origins calculated with recent high level ab initio 6D potential surface predictions for H3O^+ and isotopomers [Huang et al.,J. Chem.Phys. 118, 5431 (2003); Rajamaki et al., J. Chem. Phys. 118, 10929 (2003)] are in very encouraging agreement with the current experimental results.
Journal of Chemical Physics
hydronium ion, IR spectroscopy, slit jet discharge, tunneling
, Uy, D.
, Davis, S.
, Child, M.
and Nesbitt, D.
Supersonically Cooled Moleculear Ions in a Slit-Jet Discharge: High-Resolution Infrared Spectrscopy and Tunneling Dynamics of HD<sub>2</sub>O+, Journal of Chemical Physics
(Accessed May 28, 2023)