1 research outputs found
Chemical probing spectroscopy of H3+ above the barrier to linearity
We have performed chemical probing spectroscopy of H3+ ions trapped in a
cryogenic 22-pole ion trap. The ions were buffer-gas cooled to 55K by
collisions with helium and argon. Excitation to states above the barrier to
linearity was achieved by a Ti:Sa laser operated between 11300 and 13300 cm-1.
Subsequent collisions of the excited H3+ ions with argon lead to the formation
of ArH+ ions that were detected by a quadrupole mass spectrometer with high
sensitivity. We report the observation of 17 previously unobserved transitions
to states above the barrier to linearity. Comparison to theoretical
calculations suggests that the transition strengths of some of these lines are
more than five orders of magnitude smaller than those of the fundamental band,
which renders them - to the best of our knowledge - the weakest H3+ transitions
observed to date.Comment: 22 pages, 5 figures, submitted to JC